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Nori is the cultivated seaweed with the highest market value in the world. Monospores from the thalli reseed the cultivating nets and provide useful secondary seedlings in nori farming, but the underlying molecular basis remains unclear. To explore crucial genes and pathways related to monospore-producing process in Phycocalida chauhanii (Pyropia chauhanii), transcriptomic analysis over the time-course of key developmental stages was carried out. According to comparative analysis, a total of 19,490 differentially expressed genes (DEGs) were identified. Based on time series trend clustering analysis, 7294 DEGs were enriched in a predominant profile 45, in good accordance with the actual temporal monospore-producing processes, exhibiting an expression trend of first upregulated and then downregulated. Gene Ontology (GO) analysis revealed that the function of these DEGs were top three enriched in GO biological processes of positive regulation of GTPase activity, signal transduction, and protein phosphorylation. KEGG pathway analysis indicated that these DEGs were top three enriched in the “mitogen-activated protein kinase (MAPK) signaling pathway, regulation of autophagy, and endocytosis”. Besides, the expression levels of 12 selected DEGs were validated by real-time quantitative PCR and proved the accuracy of RNA-seq results. Collectively, these findings provide a comprehensive landscape of the molecular mechanism underlying the formation and release of monospores, which might serve as essential basis for the identification of key genes that contribute to monospore formation.

Calmodulin (CaM) plays an important regulatory role in plant growth and development. In this study, on the basis of previous transcriptomic annotation a homolog of CaM gene (Pc-CaM7) was identified from the red alga Phycocalida chauhanii (previously known as Porphyra chauhanii). It encoded a 151 amino acids protein with 4 EF-hand regions, which was the typical structure of calmodulin family proteins. Evolutionary analysis showed that Pc-CaM7 shared conserved orthologous relationships with CaMs from Neoporphyra haitanensis (formerly Pyropia haitanensis), Porphyra umbilicalis, and Gracilariopsis chorda. During the developmental period of P. chauhanii gametophytic germlings from 25- to 50-day-old, the asexual archeospores were continuedly released from the marginal region of blades, followed by the emergence of spermatangia from 40-day-old germlings. Based on quantitative real-time PCR analysis, it showed that expression trend of Pc-CaM7 was correlated with the rule of archeospores’ formation and release, whereas in N. haitanensis without archeospore characteristic, the expression pattern of the orthologous gene (Pha_00404) was different, which increased and reached a plateau during the same developmental period. These findings suggested that Pc-CaM7 may be involved in the process of archeospores formation and release, which may provide a foundation for understanding the molecular mechanisms of asexual reproduction in Bangiales.

In this work, we prepared the epoxy-based adhesives with a binary filler system, which was composed of organosilicon modified hexagonal BN (h-BN) and α-Al2O3. H-BN platelets and α-Al2O3 nanoparticles were decorated by aminopropyltrimethoxysilane (APTMS) and glycidylpropyltrimethoxysilane (GPTMS), respectively, to form covalent links to the filler/polymer matrix interface. The surface chemical composition was investigated by Fourrier transform infrared spectroscopy (FTIR) and thermogravimetry analysis (TGA), which demonstrated that the modifiers were successfully grafted onto the surface of fillers. This modification has been confirmed beneficial to thermal conductivity so that the thermal conductivity of adhesives incorporated with modified binary fillers could reach 0.85 w/m k, which is 10% more than specimen filled with unmodified fillers, because covalent links strengthened the interface and prohibited heat diffusion. Modified Hashin–Shtrikman model was utilized to analyze thermal resistance of the binary filler system, indicating that adhesives filled with modified fillers displayed lower thermal resistance. The enhancement of interface also brought about some other positive effect, especially in the decreasing of dielectric constant ( 1014). Furthermore, the mechanical strength is significantly improved when the modified binary fillers were used.

As an economically important marine seaweed, Pyropia yezoensis can be asexually reproduced via archeospores. However, the molecular mechanism of archeospore formation remains unclear. In this study, we characterized the transcriptomes of two strains of Py. yezoensis, which are strain W′ with abundant archeospores and strain W with scarce archeospores. The 25- and 35-day-old gametophytic blades of both strains were sampled for RNA sequencing. Based on comparative transcriptomic analysis, a large number of differential expressed genes (DEGs) of four pairwise groups between samples were generated. In an effort to identify the genes related to archeospore formation, 415 consensus DEGs reflecting the difference between two strains were investigated. Gene ontology and KEGG analysis revealed that the function for these DEGs was enriched in various processes, such as translation, ribosome assembly, RNA methylation, vesicles assembly, intracellular localization of organelles, and endocytosis. According to functional analysis on 80 selected DEGs, it indicated that genes involved in calcium and MAPK signaling pathway, cytoskeletal movement, and cell wall degradation were related to the formation of archeospores. The accuracy of RNA-seq results was validated by quantitative real-time PCR of 8 selected DEGs. These findings suggest that the molecular mechanism of archeospore formation in Py. yezoensis is sophisticated and our results will serve as an essential foundation for further studies.

We have applied a rational four-step strategy to identify novel bacterial glycosyl hydrolases (GH), in combination with various fungal enzymes, in order to define an efficient enzyme cocktail to hydrolyze pretreated lignocellulosic biomass. The fungal cellulases include cellobiohydrolase I (CBH I; GH family 7A), cellobiohydrolase II (CBH II; GH family 6A), endoglucanase I (EG I; GH family 7B) and ��-glucosidase (��G; GH family 3). Bacterial endocellulases (LC1 and LC2; GH family 5), ��-glucosidase (L��G; GH family 1), endoxylanases (LX1 and LX2; GH family 10) and ��-xylosidase (L��X; GH family 52) from multiple sources were cloned, expressed and purified as well. Enzymatic hydrolysis for various enzyme combinations was performed on Ammonia Fiber Expansion (AFEX) treated corn stover at various total protein loadings (30, 15 and 10 mg enzyme/g glucan). The optimal mass ratio of enzymes necessary for obtaining high glucan and xylan yields was determined using a suitable mixture design of experiments. The optimal hybrid enzyme mixtures contain fungal cellulases (78% of total protein loading), which include CBH I (loading ranging between 9-51% of total enzyme load), CBH II (9-51%), EG I (10-50%), and bacterial hemicellulases (22% of total protein loading) comprising of LXl (13%) and L��X (9%). The hybrid mixture works effectively at 50 ��C and pH 4.5 to efficiently saccharify AFEX treated corn stover giving as high as 95% glucan and 65% xylan conversion, respectively. This strategy of screening enzyme mixtures on pretreated lignocellulose will ultimately help develop enzyme cocktails that can hydrolyze plant cell walls efficiently and economically to produce cellulosic ethanol.

Pinus densata is a homoploid hybrid species, originating from P. tabuliformis × P. yunnanensis. The physiological fitness of this natural hybrid compared to its two parental species remains unknown. In this study, we investigated physiological responses of the three species by exposing artificially breed seedlings of each to drought stress lasting 28 days. Our results suggest that, in all three species, drought affected the contents of the plants’ chlorophyll, stomatal conductance, TBARS, hydrogen peroxide, and free proline and increased the activities of antioxidant enzymes, including superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6), and peroxidase (POD; EC 1.11.1.7). The drought stress also induced significant changes in the activity of ascorbate peroxidase (APX; EC 1.11.1.11), monodehydroascorbate reductase (MDHAR; EC 1.6.5.4), dehydroascorbate reductase (DHAR; EC 1.8.5.1), glutathione reductase (GR; EC 1.6.4.2), and levels of ascorbate and glutathione in the ascorbate–glutathione cycle. The hybrid species P. densata appeared to achieve greater drought tolerance and exhibit hybrid superiority in antioxidant processes and other related physiological traits compared to the two parental species, although a few of the hybrid’s measured variables were similar to those of P. tabuliformis. However, P. yunnanensis was more sensitive to drought and appeared to have the lowest resistance to such stress. These physiological differences are largely consistent with the species’ habitat preferences, which may reflect their early genetic divergences and niche differentiation. These findings provide important information for management and forest restoration efforts of these species in the future.

Thellungiella salsuginea (Brassiaceae) is a typical halophyte which can tolerate extreme cold, drought, and salinity. In order to understand the adaptive evolution of this species in the arid habitats, it is important to know its genetic structure. In this study, 17 polymorphic microsatellite loci were isolated and characterized from an enrichment genomic library of this species. We further assessed the polymorphisms of each locus in 18 individuals from nine geographically distant populations. The number of alleles per locus ranged from six to fourteen. The observed and expected heterozygosity ranged from 0.17 to 0.28 and 0.32 to 0.45, respectively. These markers have been crossly checked in another congeneric species, T. halophila. These microsatellite markers will be useful for investigating population genetics and adaptive evolution of this species and morphological divergence between and it and the closely related species.