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Cotton is an irreplaceable economic crop currently domesticated in the human world for its extremely elongated fiber cells specialized in seed epidermis, which makes it of high research and application value. To date, numerous research on cotton has navigated various aspects, from multi-genome assembly, genome editing, mechanism of fiber development, metabolite biosynthesis, and analysis to genetic breeding. Genomic and 3D genomic studies reveal the origin of cotton species and the spatiotemporal asymmetric chromatin structure in fibers. Mature multiple genome editing systems, such as CRISPR/Cas9, Cas12 (Cpf1) and cytidine base editing (CBE), have been widely used in the study of candidate genes affecting fiber development. Based on this, the cotton fiber cell development network has been preliminarily drawn. Among them, the MYB-bHLH-WDR (MBW) transcription factor complex and IAA and BR signaling pathway regulate the initiation; various plant hormones, including ethylene, mediated regulatory network and membrane protein overlap fine-regulate elongation. Multistage transcription factors targeting CesA 4, 7, and 8 specifically dominate the whole process of secondary cell wall thickening. And fluorescently labeled cytoskeletal proteins can observe real-time dynamic changes in fiber development. Furthermore, research on the synthesis of cotton secondary metabolite gossypol, resistance to diseases and insect pests, plant architecture regulation, and seed oil utilization are all conducive to finding more high-quality breeding-related genes and subsequently facilitating the cultivation of better cotton varieties. This review summarizes the paramount research achievements in cotton molecular biology over the last few decades from the above aspects, thereby enabling us to conduct a status review on the current studies of cotton and provide strong theoretical support for the future direction. [ABSTRACT FROM AUTHOR]

N6-methyladenosine (m6A) RNA modification plays important regulatory roles in plant development and adapting to the environment, which requires methyltransferases to achieve the methylation process. However, there has been no research regarding m6A RNA methyltransferases in cotton. Here, a systematic analysis of the m6A methyltransferase (METTL) gene family was performed on twelve cotton species, resulting in six METTLs identified in five allotetraploid cottons, respectively, and three to four METTLs in the seven diploid species. Phylogenetic analysis of protein-coding sequences revealed that METTL genes from cottons, Arabidopsis thaliana, and Homo sapiens could be classified into three clades (METTL3, METTL14, and METTL-like clades). Cis-element analysis predicated the possible functions of METTL genes in G. hirsutum. RNA-seq data revealed that GhMETTL14 (GH_A07G0817/GH_D07G0819) and GhMETTL3 (GH_A12G2586/GH_D12G2605) had high expressions in root, stem, leaf, torus, petal, stamen, pistil, and calycle tissues. GhMETTL14 also had the highest expression in 20 and 25 dpa fiber cells, implying a potential role at the cell wall thickening stage. Suppressing GhMETTL3 and GhMETTL14 by VIGS caused growth arrest and even death in G. hirsutum, along with decreased m6A abundance from the leaf tissues of VIGS plants. Overexpression of GhMETTL3 and GhMETTL14 produced distinct differentially expressed genes (DEGs) in A. thaliana, indicating their possible divergent functions after gene duplication. Overall, GhMETTLs play indispensable but divergent roles during the growth of cotton plants, which provides the basis for the systematic investigation of m6A in subsequent studies to improve the agronomic traits in cotton. [ABSTRACT FROM AUTHOR]

Rocky slopes are vulnerable to landslides and mudslides, which pose a major threat to human life and property. Research is being conducted to improve the adhesion between soil and minerals by mineral-solubilizing bacteria to manage slopes scientifically and develop novel methods for slope greening. From the soil of Nanjing Mufu Mountain's weathered rock walls, we isolated various soil mineral-solubilizing soil bacteria. During the soil bacterial solubilization test, we discovered that some soil bacteria could enhance the adherence of soil to minerals; therefore, we selected three soil bacteria (NL-7, NL-8, and NL-11) with higher performance for further investigation. Controlled experiments were used to investigate the effects of soil bacteria on soil characteristics (soil moisture content, soil pH, and soil exchangeable metal content) and soil adhesion to minerals. According to the findings, soil bacteria can improve the soil's adhesion to minerals, improve the soil's capacity to hold water, regulate soil pH, and solubilize and release exchangeable calcium, magnesium, sodium, and potassium ions. A structural equation modeling analysis was performed to thoroughly examine the relationship between soil characteristics and soil adherence to minerals. The analysis findings showed that soil moisture had the greatest total and direct positive impact on soil adherence to minerals. The most significant indirect impact of soil pH on soil adhesion to minerals is mainly caused by the exchangeable sodium and magnesium ions. Additionally, soil exchangeable sodium ions can only indirectly affect the adhesion of soil to minerals, which is accomplished by controlling soil exchangeable magnesium ions. Therefore, mineral-solubilizing soil bacteria primarily work by enhancing the soil's water retention capacity to improve the soil's adherence to minerals. Our study on the effect of mineral-solubilizing bacteria on the adhesion of soil and minerals demonstrates the significant potential of mineral-solubilizing bacteria in spray seeding greening, which will provide data and theoretical support for the formation, application, and promotion of mineral-solubilizing bacteria greening methods and gradually form a new set of scientific and efficient greening methods with Chinese characteristics. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC), one of the most lethal human cancers, can be divided into head and body/tail cancers anatomically. We previously reported a prognostic relevance of tumour location in resectable PDAC. This study aimed to further explore the mechanism underlying the molecular diversity between the head and body/tail of PDACs. We detected tumour genomes in 154 resectable (surgery) and non‐resectable (biopsy) PDACs using a next‐generation sequencing panel. Wilcoxon's rank test or Fisher's exact test was used for evaluating associations between clinical characteristics, mutation frequency and survival probability between the two cohorts. Compared with pancreatic head cancers, pancreatic body/tail cancers showed significantly more enriched genomic alterations in KRAS (97.1% vs 82.4%, P = 0.004) and SMAD4 (42.0% vs 21.2%, P = 0.008). At early stages (I‐II), the SMAD4 mutation rate was significantly higher in pancreatic body/tail cancers than pancreatic head cancers (56.0% vs 26.5%, P = 0.021). At late stages (III‐IV), pancreatic body/tail cancers presented significantly higher KRAS mutation rate (100.0% vs 75.8%, P = 0.001), higher frequency of MAPK pathway mutation (100% vs 87.8%, P = 0.040) and lower rates of druggable genomic alterations (30.8% vs 57.6%, P = 0.030) than pancreatic head cancers. Our work points out that pancreatic body/tail cancer seems to be more malignant than pancreatic head cancer at late stages. [ABSTRACT FROM AUTHOR]

During leaf organogenesis, a critical step for normal leaf primordium initiation is the repression of the class 1 KNOTTED1-like homeobox ( KNOX) genes. After leaf primordia are formed, they must establish polarity for normal leaf morphogenesis. Recent studies have led to the identification of a number of genes that participate in the class 1 KNOX gene repression and/or the leaf polarity establishment. ASTMMETRIC LEAVES1 and 2 ( AS1 and AS2) are two of these genes, which are critical for both of these two processes. As a first step towards understanding the molecular genetic basis of the AS1–AS2 action, we determined the subcellular localizations of the two proteins in both tobacco BY2 cells and Arabidopsis plants, by fusing them to yellow/cyan fluorescent protein (YFP/CFP). Our data showed that AS1 and AS2 alone were predominantly localized in the nucleolus and the nucleoplasm, respectively. The presence of both AS1 and AS2 proteins in the same interphase cell demonstrated their co-localization in both nucleolus and nucleoplasm. In addition, AS1 alone was able to associate with the condensed chromosome in the metaphase cell. Our data suggest that AS1, AS2 and the AS1-AS2 protein complex may have distinct functions, which are all required for normal plant development. [ABSTRACT FROM AUTHOR]

Aerial surfaces of most land plants have epidermal hairs (trichomes). Both Arabidopsis thaliana trichomes and cotton fibers (seed hairs) are nonglandular hairs with unicellular structure. Here we out- line the recent progress on molecular dissection of Arabidopsis trichome development, including the transcription factors regulating trichome initiation, phytohormones influencing trichome density, and the cytoskeleton formation system governing trichome morphogenesis. There is increasing evidence showing that these processes also control cotton fiber production. As several cotton fiber genes are able to rescue the Arabidopsis trichome mutants, we discuss the conservation between Arabidopsis trichome and cotton fiber development. [ABSTRACT FROM AUTHOR]

The relationship among transfer and expression of auxin binding protein gene ( abp), auxin (NAA)-induced plasmalemma hyperpolarity and sensibility to auxin during protoplast culture was studied by measuring transmembrane potential difference (Em) and culturing the protoplasts of sense and antisense abp transgenic tobacco. The concentration of NAA inducing the highest degree of hyperpolarity of sense abp transgenic tobacco protoplasts was lower than the control, and in protoplast culture, their sensibility to auxin increased. The concentration of antisense abp transgenic tobacco protoplasts was higher than the control, and in protoplast culture, their sensibility to auxin decreased. These results demonstrated that ABP synthesized in endoplasmic reticulum needed to transport to cell membrane and functioned there. [ABSTRACT FROM AUTHOR]

Summary Artemisinin, the well‐known natural product for treating malaria, is biosynthesised and stored in the glandular‐secreting trichomes (GSTs) of Artemisia annua. While numerous efforts have clarified artemisinin metabolism and regulation, the molecular association between artemisinin biosynthesis and GST development remains elusive. Here, we identified AaMYC3, a bHLH transcription factor of A. annua, induced by jasmonic acid (JA), which simultaneously regulates GST density and artemisinin biosynthesis. Overexpressing AaMYC3 led to a substantial increase in GST density and artemisinin accumulation. Conversely, in the RNAi‐AaMYC3 lines, both GST density and artemisinin content were markedly reduced. Through RNA‐seq and analyses conducted both in vivo and in vitro, AaMYC3 not only directly activates AaHD1 transcription, initiating GST development, but also up‐regulates the expression of artemisinin biosynthetic genes, including CYP71AV1 and ALDH1, thereby promoting artemisinin production. Furthermore, AaMYC3 acts as a co‐activator, interacting with AabHLH1 and AabHLH113, to trigger the transcription of two crucial enzymes in the artemisinin biosynthesis pathway, ADS and DBR2, ultimately boosting yield. Our findings highlight a critical connection between GST initiation and artemisinin biosynthesis in A. annua, providing a new target for molecular design breeding of traditional Chinese medicine. [ABSTRACT FROM AUTHOR]