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The properties of nanopipettes largely rely on the materials introduced onto their inner walls, which allow for a vast extension of their sensing capabilities. The challenge of simultaneously enhancing the sensitivity and selectivity of nanopipettes for pH sensing remains, hindering their practical applications. Herein, we report insulin-modified nanopipettes with excellent pH response performances, which were prepared by introducing insulin onto their inner walls via a two-step reaction involving silanization and amidation. The pH response intensity based on ion current rectification was significantly enhanced by approximately 4.29 times when utilizing insulin-modified nanopipettes compared with bare ones, demonstrating a linear response within the pH range of 2.50 to 7.80. In addition, insulin-modified nanopipettes featured good reversibility and selectivity. The modification processes were monitored using the I-V curves, and the relevant mechanisms were discussed. The effects of solution pH and insulin concentration on the modification results were investigated to achieve optimal insulin introduction. This study showed that the pH response behavior of nanopipettes can be greatly improved by introducing versatile molecules onto the inner walls, thereby contributing to the development and utilization of pH-responsive nanopipettes. [ABSTRACT FROM AUTHOR]

The article discusses research on whole genome sequencing of Mesorhizobium strains isolated from native legumes growing in two distant Low Arctic sites to understand the population genomics of rhizobia from northern Canada. The study measured the phylogenetic and average nucleotide identity of bacterial strains and analyzed legume nodulation and symbiotic nitrogen fixation on their chromosome. It describes the growth characteristics, taxonomy, genomic structures of three Mesorhizobium strains.

Background: The fragrant flower plant Osmanthus fragrans has an extremely rare androdioecious breeding system displaying the occurrence of males and hermaphrodites in a single population, which occupies a crucial intermediate stage in the evolutionary transition between hermaphroditism and dioecy. However, the molecular mechanism of androdioecy plant is very limited and still largely unknown. Results: Here, we used SWATH-MS-based quantitative approach to study the proteome changes between male and hermaphroditic O. fragrans pistils. A total of 428 proteins of diverse functions were determined to show significant abundance changes including 210 up-regulated and 218 down-regulated proteins in male compared to hermaphroditic pistils. Functional categorization revealed that the differentially expressed proteins (DEPs) primarily distributed in the carbohydrate metabolism, secondary metabolism as well as signaling cascades. Further experimental analysis showed the substantial carbohydrates accumulation associated with promoted net photosynthetic rate and water use efficiency were observed in purplish red pedicel of hermaphroditic flower compared with green pedicel of male flower, implicating glucose metabolism serves as nutritional modulator for the differentiation of male and hermaphroditic flower. Meanwhile, the entire upregulation of secondary metabolism including flavonoids, isoprenoids and lignins seem to protect and maintain the male function in male flowers, well explaining important feature of androdioecy that aborted pistil of a male flower still has a male function. Furthermore, nine selected DEPs were validated via gene expression analysis, suggesting an extra layer of post-transcriptional regulation occurs during O. fragrans floral development. Conclusion: Taken together, our findings represent the first SWATH-MS-based proteomic report in androdioecy plant O. fragrans, which reveal carbohydrate metabolism, secondary metabolism and post-transcriptional regulation contributing to the androdioecy breeding system and ultimately extend our understanding on genetic basis as well as the industrialization development of O. fragrans. [ABSTRACT FROM AUTHOR]

Cerasus serrulata (Rosaceae) is an important flowering cherry resource which is valuable for developing new cultivars of flowering cherries. It is broadly distributed and possesses abundant variations. In this study, phylogeographic analysis was conducted to reveal the evolutionary history to better understand the genetic diversity and genetic structure of C. serrulata so as to provide more accurate molecular insights into better conservation and utilization of the germplasm resources. A total of 327 individuals from 18 wild populations were collected. Three chloroplast DNA (cpDNA) fragments (matK, trnD‐E, and trnS‐G) and the nuclear internal transcribed spacer (ITS) were utilized. The results showed a high genetic diversity at both species level and population level of C. serrulata. High genetic differentiation and the existence of the phylogeographic structure were detected. No significant expansion events were discovered. Two geographic lineages were inferred. One was confined to the Qinling Mountains and the Taihang Mountains. The other was from the Wuling Mountains to the Jiangnan Hilly Regions and then went northeast to the coast of Asia. In addition, some taxonomic treatments of the C. serrulata complex are discussed and reconsidered. Conservation and utilization strategies of wild C. serrulata germplasm resources were recommended. [ABSTRACT FROM AUTHOR]

Cerasus dielsiana (Rosaceae) is one of the most characteristic wild flowering cherry species endemic to subtropical China, with high conservation value from ornamental, economic, and ecological perspectives. To verify its spatial genetic structure and phylogeographic history, evaluation of nuclear (ITS) sequence variation in 203 individuals from 25 wild populations across its natural distribution ranges was conducted. High levels of ribotypes and nuclear diversity (Hd = 0.879 ± 0.012, π = 3.56 ± 0.16) were detected at the species level. Spatial analysis of molecular variation (SAMOVA), median-joining network and phylogenetic Neighbour-joining tree assigned the populations into four genetically distinct groups. Meanwhile, high levels of genetic differentiation among populations and strong phylogeographic patterns (Nst = 0.837 > Gst = 0.585; P < 0.05) were revealed based on the analysis of molecular variance (AMOVA). Results of neutrality tests, mismatch distribution analyses, Mantel test, barrier analyses, together with ecological niche modelling (ENM) simulation and BEAST analysis suggest a long-term demographic history (95% HPD: 3.64–8.83 Mya) of C. dielsiana, and at least three potential in situ glacial refugia as well as recent demographic expansion in eastern region have been detected. Collectively, we highlight that the combined effect of natural selection and random genetic drift under complex topography and palaeoclimatic oscillations since the Last Glacial Maximum (LGM) in subtropical China might have been the main driver to the species' allopatric differentiation. Scientific conservation and sustainable utilization for wild C. dielsiana germplasm resources were subsequently proposed. [ABSTRACT FROM AUTHOR]

A taxonomic revision of Ctenitis (C. Chr.) C. Chr. (Dryopteridaceae) from Africa and the Western Indian Ocean was carried out. Forty species are recognized, of which 12 are described as new, eight are transferred to Ctenitis from other genera, and one is elevated from variety to species and transferred from Aspidium Sw. to Ctenitis. These 21 nomenclatural novelties include C. analamazaotrensis (Rakotondr.) Hennequin & Rouhan (comb. nov.), C. brevipetiolulata Li Bing Zhang & Yi F. Duan (sp. nov.), C. bullescens Rouhan, Li Bing Zhang & Yi F. Duan (sp. nov.), C. cerea Li Bing Zhang & Yi F. Duan (sp. nov.), C. comorensis Li Bing Zhang & Yi F. Duan (sp. nov.), C. crinigera (C. Chr.) Hennequin & Rouhan (comb. nov.), C. decaryana (C. Chr.) Hennequin & Rouhan (comb. nov.), C. dentata Li Bing Zhang & Yi F. Duan (sp. nov.), C. fibrillosa (Baker) Li Bing Zhang & Yi F. Duan (comb. nov.), C. hispida (Kuhn) Li Bing Zhang & Yi F. Duan (comb. & stat. nov.), C. jouyana (Rakotondr.) Hennequin & Rouhan (comb. nov.), C. longivillosa Li Bing Zhang & Yi F. Duan (sp. nov.), C. marginalisora Li Bing Zhang & Yi F. Duan (sp. nov.), C. mayottensis Li Bing Zhang & Yi F. Duan (sp. nov.), C. multilobata Li Bing Zhang, Yi F. Duan & Rouhan (sp. nov.), C. reunionensis Hennequin, Li Bing Zhang & Yi F. Duan (sp. nov.), C. sieberiana (Kaulf.) Hennequin & Rouhan (comb. nov.), C. sparsa Li Bing Zhang & Yi F. Duan (sp. nov.), C. spekei (Baker) Li Bing Zhang & Yi F. Duan (comb. nov.), C. subcrenulata (Baker) Li Bing Zhang, Rouhan & Yi F. Duan (comb. nov.), and C. tardieu-blotiae Li Bing Zhang & Yi F. Duan (sp. nov.). A key to these species is provided; all species are described and illustrated; and information on their distribution and habitats is given. Twenty-three relevant species reported in the literature are excluded from the flora, and their taxonomy, distribution, and nomenclature are discussed. Seventeen related names are lectotypified or neotypified including Aspidium cirrhosum Schumach., A. crinitum (Poir.) Wall. var. hispida Kuhn, A. cyclochlamys Fée, A. nitidum Bory ex Willd., A. pauciflorum Kaulf., A. sulcatum Kaulf. ex Bory, C. anjenabensis Tardieu, Dryopteris blepharochlamys C. Chr., Gymnogramma subsimilis Hook., Nephrodium crinitum (Poir.) Desv. var. maritimum Cordem., N. magnum Baker, N. spekei Baker, N. welwitschii Baker, Phegopteris biformis Mett. ex Kuhn, P. bivestita Mett., Polypodium baronii Baker, and P. efulense Baker; type information of related 262 names is also given. [ABSTRACT FROM AUTHOR]

Keteleeria davidiana (Bertrand) Beissner 1891 (Pinaceae) is a rare tertiary relict plant endemic to China. However, since the main morphological characteristics used for identifying K. davidiana are variable, some taxonomic treatments within the species are still controversial. Here a complete chloroplast genome of K. davidiana representing a special genotype was assembled, which could provide more information for the taxonomic study of this species. The assembled genome was 117,642 bp in length with a large single-copy (LSC) region (74,825 bp), a small single-copy (SSC) region (40,247 bp), and two incomplete inverted repeats (IRs) regions (1285 bp each). In total, 118 genes were predicted, including 4 rRNAs, 34 tRNAs, and 80 protein-coding genes. The overall GC content of the assembled genome was 38.5%. Phylogenetic analysis showed that different accessions of K. davidiana formed a clade with relatively low support (bootstrap value = 71), which indicated a high level of sequences variation within the species. [ABSTRACT FROM AUTHOR]

Cerasus serrulata is a flowering cherry germplasm resource for ornamental purposes. In this work, we present a de novo chromosome-scale genome assembly of C. serrulata by the use of Nanopore and Hi-C sequencing technologies. The assembled C. serrulata genome is 265.40 Mb across 304 contigs and 67 scaffolds, with a contig N50 of 1.56 Mb and a scaffold N50 of 31.12 Mb. It contains 29,094 coding genes, 27,611 (94.90%) of which are annotated in at least one functional database. Synteny analysis indicated that C. serrulata and C. avium have 333 syntenic blocks composed of 14,072 genes. Blocks on chromosome 01 of C. serrulata are distributed on all chromosomes of C. avium, implying that chromosome 01 is the most ancient or active of the chromosomes. The comparative genomic analysis confirmed that C. serrulata has 740 expanded gene families, 1031 contracted gene families, and 228 rapidly evolving gene families. By the use of 656 single-copy orthologs, a phylogenetic tree composed of 10 species was constructed. The present C. serrulata species diverged from Prunus yedoensis ~17.34 million years ago (Mya), while the divergence of C. serrulata and C. avium was estimated to have occurred ∼21.44 Mya. In addition, a total of 148 MADS-box family gene members were identified in C. serrulata, accompanying the loss of the AGL32 subfamily and the expansion of the SVP subfamily. The MYB and WRKY gene families comprising 372 and 66 genes could be divided into seven and eight subfamilies in C. serrulata, respectively, based on clustering analysis. Nine hundred forty-one plant disease-resistance genes (R-genes) were detected by searching C. serrulata within the PRGdb. This research provides high-quality genomic information about C. serrulata as well as insights into the evolutionary history of Cerasus species. [ABSTRACT FROM AUTHOR]