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Background: Dendrobium catenatum is a perennial herb of the genus Dendrobium orchidaceae. It has been known as "Golden Grass, Soft Gold" since ancient times with effects of strengthening the body, benefiting the stomach, generating body fluid, nourishing Yin and clearing internal heat. The flowers of D. catenatum have anti-oxidation, immune regulation and other biological activities. The composition analysis of flowers showed that flavonoid glycosides were significantly accumulated in floral tissue. However, in the flowers of D. catenatum, there was only one case of the UDP-glycosyltransferase (UGT) responsible for the glycosylation of flavonoids has been reported., Result: In this study, a new UGT (named UGT708S6) was cloned from D. catenatum flowers rich in O-glycosides and C-glycosides, and its function and biochemical properties were characterized. Through homology comparison and molecular docking, we identified the key amino acid residues affecting the catalytic function of UGT708S6. The glycosyltransferase UGT708S6 was characterized and demonstrated C-glycosyltransferase (CGT) activity in vitro assay using phloretin and 2-hydroxynaringenin as sugar acceptors. The catalytic promiscuity assay revealed that UGT708S6 has a clear sugar donor preference, and displayed O-glycosyltransferase (OGT) activity towards luteolin, naringenin and liquiritigenin. Furthermore, the catalytic characteristics of UGT708S6 were explored, shedding light on the structural basis of substrate promiscuity and the catalytic mechanism involved in the formation of flavonoid C-glycosides. R271 was a key amino acid residue site that sustained the catalytic reaction. The smaller binding pocket resulted in the production of new O-glycosides and the reduction of C-glycosides. This highlighted the importance of the binding pocket in determining whether C-glycosides or O-glycosides were produced., Conclusions: The findings suggest that UGT708S6 holds promise as a new glycosyltransferase for synthesizing flavonoid glycosides and offer valuable insights for further understanding the catalytic mechanisms of flavonoid glycosyltransferases., Competing Interests: Declarations Ethics approval and consent to participate Not applicable. Consent for publication Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Branch length is an important plant architecture trait in cotton (Gossypium) breeding. Development of cultivars with short branch has been proposed as a main object to enhance cotton yield potential, because they are suitable for high planting density. Here, we report the molecular cloning and characterization of a semi-dominant quantitative trait locus, Short Branch Internode 1(GhSBI1), which encodes a NAC transcription factor homologous to CUP-SHAPED COTYLEDON 2 (CUC2) and is regulated by microRNA ghr-miR164. We demonstrate that a point mutation found in sbi1 mutants perturbs ghr-miR164-directed regulation of GhSBI1, resulting in an increased expression level of GhSBI1. The sbi1 mutant was sensitive to exogenous gibberellic acid (GA) treatments. Overexpression of GhSBI1 inhibited branch internode elongation and led to the decreased levels of bioactive GAs. In addition, gene knockout analysis showed that GhSBI1 is required for the maintenance of the boundaries of multiple tissues in cotton. Transcriptome analysis revealed that overexpression of GhSBI1 affects the expression of plant hormone signalling-, axillary meristems initiation-, and abiotic stress response-related genes. GhSBI1 interacted with GAIs, the DELLA repressors of GA signalling. GhSBI1 represses expression of GA signalling- and cell elongation-related genes by directly targeting their promoters. Our work thus provides new insights into the molecular mechanisms for branch length and paves the way for the development of elite cultivars with suitable plant architecture in cotton., (© 2024 The Author(s). Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.)

Background: BRVIS RADIX (BRX) family is a small gene family with the highly conserved plant-specific BRX domains, which plays important roles in plant development and response to abiotic stress. Although BRX protein has been studied in other plants, the biological function of cotton BRX-like (BRXL) gene family is still elusive., Result: In this study, a total of 36 BRXL genes were identified in four cotton species. Whole genome or segmental duplications played the main role in the expansion of GhBRXL gene family during evolutionary process in cotton. These BRXL genes were clustered into 2 groups, α and β, in which structural and functional conservation within same groups but divergence among different groups were found. Promoter analysis indicated that cis-elements were associated with the phytohormone regulatory networks and the response to abiotic stress. Transcriptomic analysis indicated that GhBRXL2A/2D and GhBRXL5A/5D were up/down-regulated in response to the different stress. Silencing of GhBRXL5A gene via virus-induced gene silencing (VIGS) improved salt tolerance in cotton plants. Furthermore, yeast two hybrid analysis suggested homotypic and heterotypic interactions between GhBRXL1A and GhBRXL5D., Conclusions: Overall, these results provide useful and valuable information for understanding the evolution of cotton GhBRXL genes and their functions in salt stress., (© 2024. The Author(s).)

The calmodulin-binding protein 60 ( CBP60 ) family is a gene family unique to plants, and its members play a crucial role in plant defense responses to pathogens and growth and development. Considering that cotton is the primary source of natural cotton textile fiber, the functional study of its CBP60 gene family members is critical. In this research, we successfully identified 162 CBP60 members from the genomes of 21 species. Of these, 72 members were found in four cotton species, divided into four clades. To understand the function of GhCBP60B in cotton in depth, we conducted a detailed analysis of its sequence, structure, cis-acting elements, and expression patterns. Research results show that GhCBP60B is located in the nucleus and plays a crucial role in cotton growth and development and response to salt and drought stress. After using VIGS (virus-induced gene silencing) technology to conduct gene silencing experiments, we found that the plants silenced by GhCBP60B showed dwarf plants and shortened stem nodes, and the expression of related immune genes also changed. In further abiotic stress treatment experiments, we found that GhCBP60B-silenced plants were more sensitive to drought and salt stress, and their POD (peroxidase) activity was also significantly reduced. These results imply the vital role of GhCBP60B in cotton, especially in regulating plant responses to drought and salt stress. This study systematically analyzed CBP60 gene family members through bioinformatics methods and explored in depth the biological function of GhCBP60B in cotton. These research results lay a solid foundation for the future use of the GhCBP60B gene to improve cotton plant type and its drought and salt resistance.

C-TERMINALLY ENCODED PEPTIDEs ( CEPs ) are a class of peptide hormones that have been shown in previous studies to play an important role in regulating the development and response to abiotic stress in model plants. However, their role in cotton is not well understood. In this study, we identified 54, 59, 34, and 35 CEP genes from Gossypium hirsutum (2n = 4x = 52, AD1), G. barbadense (AD2), G. arboreum (2n = 2X = 26, A2), and G. raimondii (2n = 2X = 26, D5), respectively. Sequence alignment and phylogenetic analyses indicate that cotton CEP proteins can be categorized into two subgroups based on the differentiation of their CEP domain. Chromosomal distribution and collinearity analyses show that most of the cotton CEP genes are situated in gene clusters, suggesting that segmental duplication may be a critical factor in CEP gene expansion. Expression pattern analyses showed that cotton CEP genes are widely expressed throughout the plant, with some genes exhibiting specific expression patterns. Ectopic expression of GhCEP46-D05 in Arabidopsis led to a significant reduction in both root length and seed size, resulting in a dwarf phenotype. Similarly, overexpression of GhCEP46-D05 in cotton resulted in reduced internode length and plant height. These findings provide a foundation for further investigation into the function of cotton CEP genes and their potential role in cotton breeding.

GEX1 (gamete expressed 1) proteins are critical membrane proteins conserved among flowering plants that are involved in the nuclear fusion and embryonic development. Herein, we identified the 32 GEX1 proteins from representative land plants. In cotton, GEX1 genes expressed in various tissues across all stages of the life cycle, especially in pollen. Subcellular localization indicated the position of GhGEX1 protein was localized in the endoplasmic reticulum. Experimental research has demonstrated that GhGEX1 has the potential to improve the partial abortion phenotype in Arabidopsis. CRISPR/Cas9-mediated knockout of GhGEX1 exhibited the seed abortion. Paraffin section of the ovule revealed that the polar nuclear fusion of ghgex1 plants remains at a standstill when the wild type has developed into a normal embryo. Comparative transcriptome analysis showed that the DEGs of reproductive-related processes and membrane-related processes were repressed in the pollen of knockout lines. The predicted protein interactions showed that GhGEX1 probably functioned through interactions with proteins related to reproduction and membrane. From all these investigations, it was possible to conclude that the GEX1 proteins are evolutionarily conserved in flowering plants and elucidated the pivotal roles during fertilization and early embryonic development in cotton., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Background: Phospholipases As (PLAs) are acyl hydrolases that catalyze the release of free fatty acids in phospholipids and play multiple functions in plant growth and development. The three families of PLAs are: PLA1, PLA2 (sPLA), and patatin-related PLA (pPLA). The diverse functions that pPLAs play in the growth and development of a broad range of plants have been demonstrated by prior studies., Methods: Genome-wide analysis of the pPLA gene family and screening of genes for expression verification and gene silencing verification were conducted. Additionally, pollen vitality testing, analysis of the pollen expression pattern, and the detection of POD, SOD, CAT, MDA, and H 2 O 2 were performed., Result: In this study, 294 pPLAs were identified from 13 plant species, including 46 GhpPLAs that were divided into three subfamilies (I-III). Expression patterns showed that the majority of GhpPLAs were preferentially expressed in the petal, pistil, anther, and ovule, among other reproductive organs. Particularly, GhpPLA23 and GhpPLA44, were found to be potentially important for the reproductive development of G. hirsutum. Functional validation was demonstrated by VIGS which showed that reduced expression levels of GhpPLA23 and GhpPLA44 in the silenced plants were associated with a decrease in pollen activity. Moreover, a substantial shift in ROS and ROS scavengers and a considerable increase in POD, CAT, SOD, and other physiological parameters was found out in these silenced plants. Our results provide plausibility to the hypothesis that GhpPLA23 and GhpPLA44 had a major developmental impact on cotton reproductive systems. These results also suggest that pPLAs are important for G. hirsutum's reproductive development and suggest that they could be employed as potential genes for haploid induction., Conclusions: The findings of the present research indicate that pPLA genes are essential for the development of floral organs and sperm cells in cotton. Consequently, this family might be important for the reproductive development of cotton and possibly for inducing the plant develop haploid progeny., (© 2023. The Author(s).)

Background: Cytokinin oxidase/dehydrogenase (CKX) plays a vital role in response to abiotic stress through modulating the antioxidant enzyme activities. Nevertheless, the biological function of the CKX gene family has yet to be reported in cotton., Result: In this study, a total of 27 GhCKXs were identified by the genome-wide investigation and distributed across 18 chromosomes. Phylogenetic tree analysis revealed that CKX genes were clustered into four clades, and most gene expansions originated from segmental duplications. The CKXs gene structure and motif analysis displayed remarkably well conserved among the four groups. Moreover, the cis-acting elements related to the abiotic stress, hormones, and light response were identified within the promoter regions of GhCKXs. Transcriptome data and RT-qPCR showed that GhCKX genes demonstrated higher expression levels in various tissues and were involved in cotton's abiotic stress and phytohormone response. The protein-protein interaction network indicates that the CKX family probably participated in redox regulation, including oxidoreduction or ATP levels, to mediate plant growth and development. Functionally identified via virus-induced gene silencing (VIGS) found that the GhCKX14 gene improved drought resistance by modulating the antioxidant-related activitie., Conclusions: In this study, the CKX gene family members were analyzed by bioinformatics, and validates the response of GhCKX gene to various phytohormone treatment and abiotic stresses. Our findings established the foundation of GhCKXs in responding to abiotic stress and GhCKX14 in regulating drought resistance in cotton., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Oil pollution has caused more and more serious damages to the environment, especially to water. Oil and water separation technologies based on high-performance absorbing materials have attracted extensive attentions. Herein, elasticity-enhanced bacterial cellulose (BC) aerogel is synthesized for oil/water separation through thermochemical vapor deposition (CVD) catalyzed by 1, 2, 3, 4-butanetetracarboxylic acid (BTCA). BTCA has two functions, namely, esterification with BC and catalyzing CVD. The prepared aerogel could be recovered soon after being compressed and the elastic recovery was >90 % at set maximum deformation of 80 %. And, it also exhibits vigorous fatigue resistance with an elastic deformation of >80 % after 50 cycles. The high elastic and hydrophobic aerogel is very suitable for absorbing and desorbing oils by simple mechanical squeezing. The adsorption capacity for n-hexane and dichloroethane maintain 87 % and 81 % after 50 cycles, respectively, which implies robust reusability. Importantly, the CVD could also be catalyzed by other solid acids such as citric acid and vitamin C. This design and fabrication method offers a novel avenue for the preparation of hydrophobic bacterial cellulose aerogel with high elasticity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Quinones are highly reactive oxidants and play an essential role in inducing quality deterioration of fruit and vegetable products. Here, a novel stable isotope-labeling approach in combination with high-resolution tandem mass spectrometry UPLC-Q-TOF/MS and UPLC-Q-Exactive Orbitrap/MS, was successfully applied in tracking quinone reaction pathways in both real wines and model reaction systems. Unexpectedly, the binding products of quinone-quinone and quinone-catechol that are not derived from either nucleophilic reaction or redox reaction were discovered and showed the significant high peak area.Self-coupling reactions of semiquinone radicals might provide a possible interpretation for the formation of quinone-quinone products, and a charge transfer reaction coupled with a complementary donor-acceptor interaction is feasibly responsible for the products with a quinone-catechol structure. These findings endow a new perspective for quinone metabolic pathway in foods., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Filamin protein is characterized by an N-terminal actin-binding domain that is followed by 24 Ig (immunoglobulin)-like repeats, which act as hubs for interactions with a variety of proteins. In humans, this family has been found to be involved in cancer cell invasion and metastasis and can be involved in a variety of growth signal transduction processes, but it is less studied in plants. Therefore, in this study, 54 Filamin gene family members from 23 plant species were investigated and divided into two subfamilies: FLMN and GEX2. Subcellular localization showed that most of the Filamin gene family members were located in the cell membrane. A total of 47 Filamin gene pairs were identified, most of which were whole-genome copies. Through the analyses of cis -acting elements, expression patterns and quantitative fluorescence, it was found that GH_ A02G0519 and GH_ D02G0539 are mainly expressed in the reproductive organs of upland cotton, and their interacting proteins are also related to the fertilization process, whereas GH_A02G0216 and GH_D02G0235 were related to stress. Thus, it is speculated that two genes of the GEX2 subfamily ( GH_A02G0519 and GH_D02G0539 ) may be involved in the reproductive development of cotton and may affect the fertilization process of cotton. This study provides a theoretical basis for the further study of the cotton Filamin gene family.

The complex chemical structure of polypeptide and the imperfection of processing technology cause the mechanical properties of regenerated keratin to be hard and brittle. This defect seriously affects the application prospects of keratin materials. To solve the above problems, α-lipoic acid modified keratin (KER) was blended with Polyamide 6 (PA6) and prepared into composite fibers via the wet-spinning method in this work. The spinnability and spinning conditions of the KER/PA6 blend solution were analyzed by rheological theory. The results illustrated that keratin solution will easily form a gel state under certain temperatures and concentrations, which was not conducive to the preparation of regenerated fiber. When the temperature was 45 °C and the mass fraction was 10 %, the viscosity and rheology of the solution were appropriate. The rheological properties of the blend solution showed that too much keratin would make the solution easy to gel, which was not conducive to the preparation of regenerated fibers and may affect the fiber properties. On this basis, the prepared composite fibers were characterized to explore the macromolecular aggregation state of keratin and PA6 in fibers. FT-IR and XRD results proved that there was no chemical reaction between keratin and PA6 in the composite fibers, which belonged to physical blending. At the same time, the two polymers had good compatibility and can be blended at the molecular level. SEM, DSC, and tensile strength test results indicated that when the proportion of keratin was too high, the structure and properties of the composite fibers will have obvious defects, which was consistent with the rheological analysis. Therefore, the blend ratio of keratin/PA6 was determined to be 3:7. Under this condition, the fibers exhibited a homogeneous structure and good thermal properties, especially its mechanical properties were close to wool fibers. The KER/PA6 composite fibers show important research value and can also provide technical reference for the development of regenerated biomass materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

F-box/LR ( FBXL ), Leucine-rich repeats in F-box proteins, belongs to the Skp1-Cullin1-F-box protein (SCF) E3 ligase family. FBXL genes play important roles in plant growth, such as plant hormones, responses to environmental stress, and floral organ development. Here, a total of 518 FBXL genes were identified and analyzed in six plant species. Phylogenetic analysis showed that AtFBXL s, VvFBXL s, and GrFBXL s were clustered into three subfamilies (Ⅰ-Ⅲ). Based on the composition of the F-box domain and carboxyl-terminal amino acid sequence, FBXL proteins were classified into three types (Type-A/-B/-C). Whole-genome duplication (WGD) along with tandem duplications and segmental contributed to the expansion of this gene family. The result indicates that four cotton species are also divided into three subfamilies. FBXL s in cotton were classified into three clades by phylogenetic and structural analyses. Furthermore, expression analyses indicated that the expression patterns of GhFBXL s in different cotton tissues were different. The highly expressed of GH_A07G2363 in 5-8 mm anthers, indicates that this gene might play a role in the reproductive process, providing candidate genes for future studies on cotton fertility materials. This study provides an original functional opinion and a useful interpretation of the FBXL protein family in cotton.

Non-enzymatic browning induced by polyphenol oxidation is an essential problem during the processing and storage of fruit and vegetable products. Here, the non-enzymatic browning mechanism between catechin (CAT), chlorogenic acid (CQA) and their corresponding quinones was investigated in model systems during the 32-d long-term storage. The results showed that CAT and catechin quinone (CATQ), which contains both A ring with a resorcinol structure and an o-diphenol B ring, are important precursors for browning, while chlorogenic acid (CQA) has a minor effect on browning. Chlorogenic acid quinone (CQAQ)-mediated CAT oxidation (k CAT-degradation  = 0.0458 mol·L -1 ·d -1 ) was faster than CAT autoxidation (k CAT-degradation  = 0.0006 mol·L -1 ·d -1 ), and there was no significant difference between CQAQ-mediated CAT oxidation and CATQ-mediated CQA oxidation. These indicate that CQAQ oxidizes CAT to CATQ quickly, and CATQ reacts with CAT subsequently through complex reactions to produce brown pigments in model systems during long-term storage., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lingjun Ma reports financial support was provided by National Natural Science Foundation of China. Lingjun Ma reports financial support was provided by Young Elite Scientists Sponsorship Program. The remaining authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Drought-induced 19 (Di19) protein is a Cys2/His2 (C2H2) type zinc-finger protein, which plays a crucial role in plant development and in response to abiotic stress. This study systematically investigated the characteristics of the GhDi19 gene family, including the member number, gene structure, chromosomal distribution, promoter cis-elements, and expression profiles. Transcriptomic analysis indicated that some GhDi19s were up-regulated under heat and salt stress. Particularly, two nuclear localized proteins, GhDi19-3 and GhDi19-4 , were identified as being in potential salt stress responsive roles. GhDi19-3 and GhDi19-4 decreased sensitivity under salt stress through virus-induced gene silencing (VIGS), and showed significantly lower levels of H 2 O 2 , malondialdehyde (MDA), and peroxidase (POD) as well as significantly increased superoxide dismutase (SOD) activity. This suggested that their abilities were improved to effectively reduce the reactive oxygen species (ROS) damage. Furthermore, certain calcium signaling and abscisic acid (ABA)-responsive gene expression levels showed up- and down-regulation changes in target gene-silenced plants, suggesting that GhDi19-3 and GhDi19-4 were involved in calcium signaling and ABA signaling pathways in response to salt stress. In conclusion, GhDi19-3 and GhDi19-4, two negative transcription factors, were found to be responsive to salt stress through calcium signaling and ABA signaling pathways.

Oxidized sucrose is a non-formaldehyde crosslinking agent with many applications in polymer crosslinking and modification, such as in the preparation of starch films and protein films. However, research on the structure of oxidized sucrose is lacking. In this paper, oxidized sucrose was synthesized through selective oxidation of sodium periodate. By LC-MS, FTIR, TGA, NMR, and HRMS analyses, it was shown that oxidized sucrose existed in the form of a hydrate, and the tetraaldehyde oxidized sucrose could isomerize into the form of two six-membered hemiacetal rings. The structure of oxidized sucrose was also verified by theoretical calculations. Furthermore, the diffusional properties of oxidized sucrose were investigated by the rolling-film method. Finally, it was found that oxidized sucrose used as a crosslinking agent could effectively improve the wrinkle recovery performance of cotton fabrics.

The Jumonji C (JmjC) domain-containing protein family, an important family of histone demethylase in plants, can directly reverse histone methylation and play important roles in various growth and development processes. In the present study, 51 JmjC genes ( GhJMJs ) were identified by genome-wide analysis in upland cotton ( Gossypium hirsutum ), which can be categorized into six distinct groups by phylogenetic analysis. Extensive syntenic relationship events were found between G. hirsutum and Theobroma cacao . We have further explored the putative molecular regulatory mechanisms of the JmjC gene family in cotton. GhJMJ24 and GhJMJ49 were both preferentially expressed in embryogenic callus compared to nonembryogenic callus in cotton tissue culture, which might be regulated by transcription factors and microRNAs to some extent. Further experiments indicated that GhJMJ24 and GhJMJ49 might interact with SUVH4, SUVH6, DDM1, CMT3, and CMT1 in the nucleus, potentially in association with demethylation of H3K9me2. Taken together, our results provide a foundation for future research on the biological functions of GhJMJ genes in cotton, especially in somatic embryogenesis in cotton tissue culture, which is crucial for the regeneration of transgenic plants., Competing Interests: XF was employed by the Shandong Denghai Shengfeng Seed Industry Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Zhu, Yao, Fang, Li, Li, Wang, Wang, Wu, Pan, Feng, Chen and Zhang.)

Fertilization is essential to sexual reproduction of flowering plants. EC1 (EGG CELL 1) proteins have a conserved cysteine spacer characteristic and play a crucial role in double fertilization process in many plant species. However, to date, the role of EC1 gene family in cotton is fully unknown. Hence, detailed bioinformatics analysis was explored to elucidate the biological mechanisms of EC1 gene family in cotton. In this study, we identified 66 genes in 10 plant species in which a total of 39 EC1 genes were detected from cotton genome. Phylogenetic analysis clustered the identified EC1 genes into three families (I-III) and all of them contain Prolamin-like domains. A good collinearity was observed in the synteny analysis of the orthologs from cotton genomes. Whole-genome duplication was determined to be one of the major impetuses for the expansion of the EC1 gene family during the process of evolution. qRT-PCR analysis showed that EC1 genes were highly expressed in reproductive tissues under multiple stresses, signifying their potential role in enhancing stress tolerance or responses. Additionally, gene interaction networks showed that EC1 genes may be involved in cell stress and response transcriptional regulator in the synergid cells and activate the expression of genes required for pollen tube guidance. Our results provide novel functional insights into the evolution and functional elucidation of EC1 gene family in cotton.

Members of DOMAIN OF UNKNOWN FUNCTION 679 membrane protein (DMP) gene family, a type of plant-specific membrane proteins, have been proposed to function in various physiological processes such as reproductive development and senescence in plants. Here, a total of 174 DMP genes were identified and analyzed in 16 plant species (including 58 DMPs in four cotton species). Phylogenetic analysis showed that these DMPs could be clustered into five subfamilies (I-V). 137 duplicated cotton gene pairs were identified and most duplicate events were formed by whole-genome duplication (WGD)/segmental duplications. Expression analysis revealed that most of cotton DMPs were mainly expressed in the reproductive organs (the sepal, petal, pistil and anther) and the fiber of secondary cell wall stage. GhDMPs promoter regions containing the different cis-elements also showed different responses to abiotic stress. In addition, gene interaction networks showed that DMPs, as an endomembrane system, were involved in plant senescence process and flower reproductive development. We speculated GhDMP8-A/-D, GbDMP8-A/-D could be used as some candidate gene for inducing cotton haploid. This genome-wide study provides a systematic analysis of the cotton DMP gene family, and further insights towards understanding the potential functions of candidate genes., (Copyright © 2021 Elsevier B.V. All rights reserved.)

SUN-domain containing proteins are crucial nuclear membrane proteins involved in a plethora of biological functions, including meiosis, nuclear morphology, and embryonic development, but their evolutionary history and functional divergence are obscure. In all, 216 SUN proteins from protists, fungi, and plants were divided into two monophyletic clades (Cter-SUN and Mid-SUN). We performed comprehensive evolutionary analyses, investigating the characteristics of different subfamilies in plants. Mid-SUNs further evolved into two subgroups, SUN3 and SUN5, before the emergence of the ancestor of angiosperms, while Cter-SUNs retained one subfamily of SUN1. The two clades were distinct from each other in the conserved residues of the SUN domain, the TM motif, and exon/intron structures. The gene losses occurred with equal frequency between these two clades, but duplication events of Mid-SUNs were more frequent. In cotton, SUN3 proteins are primarily expressed in petals and stamens and are moderately expressed in other tissues, whereas SUN5 proteins are specifically expressed in mature pollen. Virus-induced knock-down and the CRISPR/Cas9-mediated knockout of GbSUN5 both showed higher ratios of aborted seeds, although pollen viability remained normal. Our results indicated divergence of biological function between SUN3 and SUN5, and that SUN5 plays an important role in reproductive development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Yuan, Pan, Zhu, Li, Yao, Li, Fang, Liu, Wang, Li, Chen and Zhang.)

Cotton ( Gossypium ) seed fibers can be divided into lint (long) or fuzz (very short). Using fiberless (fuzzless-lintless) mutants, the lint initiation gene Li 3 was identified by map-based cloning. The gene is an R2R3-MYB transcription factor located on chromosome D12 ( GhMML3_D12 ). Sequence analysis revealed that li 3 is a loss-of-function allele containing a retrotransposon insertion in the second exon that completely blocks the gene's expression. The genetic loci n 2 and n 3 underlying the recessive fuzzless phenotype in Gossypium hirsutum were also mapped. The genomic location of n 3 overlapped with that of the dominant fuzzless locus N 1 , and n 3 appeared to be a loss-of-function allele caused by a single nucleotide polymorphism (SNP) mutation in the coding region of GhMML3_A12 . The n 2 allele was found to be co-located with li 3 and originated from G. babardense . n 2 and li 3 are possibly the multiple alleles of the GhMML3_D12 gene. Genetic analysis showed that Li 3 and N 3 are a pair of homologs with additive effects for the initiation of fibers (fuzz or lint). In addition, the presence of another locus was speculated, and it appeared to show an inhibitory effect on the expression of GhMML3 . These findings provide new information about the genetic factors affecting the initiation of fibers in cotton., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Chen, Li, Zhu, Fang, Zhao, Guo, Wang, Yuan, Lu, Liu, Yao and Zhang.)

The open-bud ( ob ) mutants in cotton display abnormal flower buds with the stigma and upper anthers exposed before blooming. This characteristic is potentially useful for the efficient production of hybrid seeds. The recessive inheritance pattern of the ob phenotype in allotetraploid cotton is determined by duplicated recessive loci ( ob1ob1ob2ob2 ). In this study, ob1, which is a MIXTA-like MYB gene on chromosome D13 ( MML10_Dt ), was identified by map-based cloning. In Gossypium barbadense (Gb) acc. 3-79, a single nucleotide polymorphism (SNP) (G/A) at the splice site of the first intron and an 8-bp deletion in the third exon of MML10_Dt were found, which are the causative mutations at the ob1 loci. A 1783-bp deletion that leads to the loss of the third exon and accounts for the causal variation at the ob2 loci was found in MML10_At of Gossypium hirsutum (Gh) acc. TM-1. The ob phenotype results from the combination of these two loss-of-function loci. Genotyping assays showed that the ob1 and ob2 loci appeared after the formation of allotetraploid cotton and were specific for Gb and Gh, respectively. All Gb lines and most Gh cultivars carry the single corresponding mutant alleles. Genome-wide transcriptome analysis showed that some of the MYB genes and genes related to cell wall biogenesis, trichome differentiation, cytokinin signal transduction, and cell division were repressed in the ob mutants, which may lead to suppression of petal growth. These findings should be of value for breeding superior ob lines in cotton., (Copyright © 2020 Chen, Yao, Li, Zhu, Guo, Fang, Zhao, Wang, Yuan, Lu and Zhang.)

Background: Members of the AT-HOOK MOTIF CONTAINING NUCLEAR LOCALIZED (AHL) family are involved in various plant biological processes via protein-DNA and protein-protein interaction. However, no the systematic identification and analysis of AHL gene family have been reported in cotton., Results: To investigate the potential functions of AHLs in cotton, genome-wide identification, expressions and structure analysis of the AHL gene family were performed in this study. 48, 51 and 99 AHL genes were identified from the G.raimondii, G.arboreum and G.hirsutum genome, respectively. Phylogenetic analysis revealed that the AHLs in cotton evolved into 2 clades, Clade-A with 4-5 introns and Clade-B with intronless (excluding AHL20-2). Based on the composition of the AT-hook motif(s) and PPC/DUF 296 domain, AHL proteins were classified into three types (Type-I/-II/-III), with Type-I AHLs forming Clade-B, and the other two types together diversifying in Clade-A. The detection of synteny and collinearity showed that the AHLs expanded with the specific WGD in cotton, and the sequence structure of AHL20-2 showed the tendency of increasing intron in three different Gossypium spp. The ratios of non-synonymous (Ka) and synonymous (Ks) substitution rates of orthologous gene pairs revealed that the AHL genes of G.hirsutum had undergone through various selection pressures, purifying selection mainly in A-subgenome and positive selection mainly in D-subgenome. Examination of their expression patterns showed most of AHLs of Clade-B expressed predominantly in stem, while those of Clade-A in ovules, suggesting that the AHLs within each clade shared similar expression patterns with each other. qRT-PCR analysis further confirmed that some GhAHLs higher expression in stems and ovules., Conclusion: In this study, 48, 51 and 99 AHL genes were identified from three cotton genomes respectively. AHLs in cotton were classified into two clades by phylogenetic relationship and three types based on the composition of motif and domain. The AHLs expanded with segmental duplication, not tandem duplication. The expression profiles of GhAHLs revealed abundant differences in expression levels in various tissues and at different stages of ovules development. Our study provided significant insights into the potential functions of AHLs in regulating the growth and development in cotton.

An original Von Koch curve-shaped tipped electrospinneret was used to prepare a polyimide (PI)-based nanofiber membrane. A multilayer Al 2 O 3 @polyimide/polyethylene/Al 2 O 3 @polyimide (APEAP) composite membrane was tactfully designed with an Al 2 O 3 @ polyimide (AP) membrane as outer shell, imparting high temperature to the thermal run-away separator performance and a core polyethylene (PE) layer imparts the separator with a thermal shut-down property at low temperature (123 °C). An AP electrospun nanofiber was obtained by doping Al 2 O 3 nanoparticles in PI solution. The core polyethylene layer was prepared using polyethylene powder and polyterafluoroethylene (PTFE) miniemulsion through a coating process. The addition of PTFE not only bonds PE power, but also increases the adhesion force between the PE and AP membranes. As a result, the multilayer composite separator has high safety, outstanding electrochemical properties, and better cycling performance as a lithium-ion battery separator.

Introduction: The phosphatidylethanolamine-binding protein (PEBP) gene family plays a crucial role in seed germination, reproductive transformation, and other important developmental processes in plants, but its distribution in Gossypium genomes or species, evolutionary properties, and the fates of multiple duplicated genes remain unclear., Objectives: The primary objectives of this study were to elucidate the distribution and characteristics of PEBP genes in Gossypium, as well as the evolutionary pattern of duplication and deletion, and functional differentiation of PEBPs in plants., Methods: Using the PEBP protein sequences in Arabidopsis thaliana as queries, blast alignment was carried out for the identification of PEBP genes in four sequenced cotton species. Using the primers designed according to the PEBP genome sequences, PEBP genes were cloned from 15 representative genomes of Gossypium genus, and the gene structure, CDS sequence, protein sequence and properties were predicted and phylogenetic analysis was performed. Taking PEBP proteins of grape as reference, grouping of orthologous gene, analysis of phylogeny and divergence of PEBPs in nine species were conducted to reconstruct the evolutionary pattern of PEBP genes in plants., Results: We identified and cloned 160 PEBPs from 15 cotton species, and the phylogenetic analysis showed that the genes could be classified into the following three subfamilies: MFT-like, FT-like and TFL1-like. There were eight single orthologous group (OG) members in each diploid and 16 double OG members in each tetraploid. An analysis of the expression and selective pressure indicated that expression divergence and strong purification selection within the same OG presented in the PEBP gene family., Conclusion: An evolutionary pattern of duplication and deletion of the PEBP family in the evolutionary history of Gossypium was suggested, and three pairs of genes resulted from different whole-genome duplication events.

Key Message: Nulliplex-branch (nb) mutants in cotton display a specific architecture. The gene responsible for the nb phenotype was identified, and its modulation mode was further studied. Plant architecture is an important agronomic factor influencing various traits such as yield and variety adaptability in crop plants. Cotton (Gossypium) simultaneously displays monopodial and sympodial growth. Nulliplex-branch (nb) mutants showing determinate sympodial shoots have been reported in both G. hirsutum (Ghnb) and G. barbadense (Gbnb). In this study, the gene responsible for the nb phenotype was identified. GhNB and GbNB were found to be allelic loci and are TERMINAL FLOWER 1 orthologs on the Dt subgenome, though the At copies remain native. Sequencing and association analyses identified four (Gh-nb1-Gh-nb4) and one (Gb-nb1) type of point mutation in the coding sequences of Ghnb and Gbnb, respectively. The NB gene was mainly expressed in the root and shoot apex, and expression rhythms were also observed in these tissues, suggesting that the expression of the NB gene could be regulated by photoperiod. Constitutive overexpression of GhNB suppresses the differentiation of the reproductive shoots. Knockout of both copies of GhNB caused the main and lateral shoots to terminate in flowers, which is a more determinate architecture than that of the nb mutants and implies that its function might be dosage dependent. A protein lipid overlay assay indicated that the amino acid substitutions in Gh-nb1 and Gb-nb1 weaken the ligand-binding activity of the NB protein in vitro. These findings suggest that the NB gene plays crucial roles in regulating the determinacy of shoots, and the modulation of this gene should constitute an effective crop improvement approach through adjusting the growth habit of cotton.

Much research has focused on improvement of the structural and mechanical properties of regenerated keratin materials by physical or chemical methods in recent years. In this research, regenerated keratin materials were modified with graphene oxide (GO). The properties of modified keratin films and the mechanism of interaction between GO and keratin macromolecules were studied. The SEM and XRD test results showed that the orientation of keratin macromolecules could be effectively improved by GO, which favored improvement of the keratin material's crystallinity and made the films more uniform and compact. The thermal stability and mechanical properties of GO-modified keratin films were also improved significantly. At the same time, the reaction mechanism between keratin and GO materials was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), FT-IR, and Raman spectroscopy. It was shown that there was no chemical reaction between GO and keratin molecules, and the interaction between them was mainly via hydrogen bonding and van der Waals forces.

Wool fibers usually need shrinkproofing finishing. The enzyme process is an eco-friendly technology but the traditional exhaustion treatment usually takes excessive time. This study developed a novel multiple padding shrinkproofing process of wool with Savinase 16L and an organic phosphine compound {[HO(CH₂) n ]₃P, n ∈ (1, 10)}. SEM and XPS analyses were employed to compare the wool treated respectively by exhaustion and by padding to reveal the effect of multiple padding. The results showed that treated wool fiber achieved the requirement of machine-washable (area shrinkage less than 8% according to standard TM 31 5 × 5A) in 2.5 min by the padding process. The padding process can control the adsorbance of enzyme on wool, which makes treatment more uniform and avoids strong damage of the wool. Also, the removal efficiency of the disulfide bond was about 15 times as much as in the exhaustion treatment in 2.5 min. The average catalytic rate of the padding process was 14 times faster than the exhaustion process, and the process time (2.5 min) decreased by 32.5 min compared with the exhaustion process (35 min). Multiple padding techniques can achieve continuous production and replace the environmentally harmful chlorination process. Our results provide the underlying insights needed to guide the research of the enzyme process application.

Key Message: Using bulked segregant analysis based on next-generation sequencing, the recessive nulliplex-branch gene was mapped between two SNP markers ~600 kb apart. In a "nulliplex-branch" cotton mutant, most of the flowers arise directly from leaf axils on the main shoot, which usually does not have a fruiting branch. A nulliplex-branch is a useful trait by which to study cotton architecture; however, the genetic basis of this mutant has remained elusive. In this study, bulked segregant analysis combined with next-generation sequencing technology was used to finely map the underlying genes that result in a nulliplex-branch plant. The nulliplex-branch Pima cotton variety, Xinhai-18, was crossed with the normal branch upland cotton line, TM-1, resulting in an F2 population. The nulliplex-branch trait was found to be controlled by the recessive gene gb_nb1. Allelic single-nucleotide polymorphisms (SNPs) were discovered by reduced-representation sequencing between the parents, and their profiles were also characterized in the nulliplex-branch and normal branch bulks constructed using the F2 plants. A candidate ~9.0 Mb-long region comprising 42 SNP markers was found to be associated with gb_nb1, which helped localize it at the ~600-kb interval on Chr 16 by segregation analysis in the F2 population. The closely linked markers with gb_nb1 developed in this study will facilitate the marker-assisted selection of the nulliplex-branch trait, and the fine map constructed will accelerate map-based cloning of gb_nb1.