Peripheral nerve fibroblasts secrete neurotrophic factors to promote axon growth of motoneurons

Peripheral nerve fibroblasts play a critical role in nerve development and regeneration.Our previous study found that peripheral nerve fibroblasts have different sensory and motor phenotypes.Fibroblasts of different phenotypes can guide the migration of Schwann cells to the same sensory or motor phenotype.In this study,we analyzed the different effects of peripheral nerve-derived fibroblasts and cardiac fibroblasts on motoneurons.Compared with cardiac fibroblasts,peripheral nerve fibroblasts greatly promoted motoneuron neurite outgrowth.Transcriptome analysis results identified 491 genes that were differentially expressed in peripheral nerve fibroblasts and cardiac fibroblasts.Among these,130 were significantly upregulated in peripheral nerve fibroblasts compared with cardiac fibroblasts.These genes may be involved in axon guidance and neuron projection.Three days after sciatic nerve transection in rats,peripheral nerve fibroblasts accumulated in the proximal and distal nerve stumps,and most expressed brain-derived neurotrophic factor.In vitro,brain-derived neurotrophic factor secreted from peripheral nerve fibroblasts increased the expression ofβ-actin and F-actin through the extracellular regulated protein kinase and serine/threonine kinase pathways,and enhanced motoneuron neurite outgrowth.These findings suggest that peripheral nerve fibroblasts and cardiac fibroblasts exhibit different patterns of gene expression.Peripheral nerve fibroblasts can promote motoneuron neurite outgrowth.

Full-length mRNA sequencing in Saccharina japonica and identification of carbonic anhydrase genes

The carbonic anhydrases(CAs)are a group of enzymes that play an important role in the absorption and transportation of CO_(2) in Saccharina japonica.They are encoded by a superfamily of genes with seven subtypes that are unrelated in sequence but share conserved function in catalyzing the reversible conversion of CO_(2) and HCO_(3)^(-).Here we have characterized the CA members in the transcriptome of S.japonica using Single-molecule real-time(SMRT)sequencing technology.Approximately 9830.4 megabases from 5,028,003 quality subreads were generated,and they were assembled into 326,512 full-length non-chimeric(FLNC)reads,with an average flnc read length of 2181 bp.After removing redundant sequences,79,010 unique transcripts were obtained of which 38,039 transcripts were successfully annotated.From the full-length transcriptome,we have identified 7 full-length cDNA sequences for CA genes(4α-CAs,1β-CAs and 2γ-CAs)and assessed for their potential functions based on phylogenetic analysis.Characterizations of CAs will provide the ground for future studies to determine the involvement of CAs in inorganic carbon absorption and transportation in S.japonica.

Identification of differently expressed mRNAs by peripheral blood mononuclear cells in Vogt-Koyanagi-Harada disease

Vogt-Koyanagi-Harada disease(VKH)is a rare autoimmune disease characterized by diffuse and bilateral uveitis,alopecia,tinnitus,hearing loss,vitiligo and headache.The transcriptional expression pattern of peripheral blood mononuclear cells(PBMC)in VKH remains largely unknown.In this study,mRNA sequencing was conducted in PBMC from VKH patients with active uveitis before treatment(n=7),the same patients after prednisone combined with cyclosporine treatment(n=7)and healthy control subjects strictly matched with gender and age(n=7).We found 118 differentially expressed genes(DEGs)between VKH patients and healthy control subjects,and 21 DEGs between VKH patients before and after treatment.TRIB1 was selected as a potential biomarker to monitor the development of VKH according to the mRNA sequencing.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis were performed to predict the possible biological functions and signaling pathways of DEGs.Neutrophil degranulation,peptidase regulator activity,secretory granule membrane,cellular response to peptide,growth factor binding and cell projection membrane were enriched as GO annotations of DEGs.Arachidonic acid metabolism and mitogen-activated protein kinase(MAPK)signaling pathway were potential signaling pathways involved in pathogenesis and drug response of VKH.A protein–protein interaction(PPI)network was constructed by STRING,and colony stimulating factor 1 receptor(CSF1R)was identified as the hubgene of all DEGs by Cytoscape.The cell type presumed to contribute to the aberrant expression of DEGs was analyzed with the use of publicly available single-cell sequencing data of PBMC from a healthy donor and single-cell sequencing dataset of monocytes from VKH patients.Our findings may help to decipher the underlying cellular and molecular pathogenesis of VKH and may lead novel therapeutic applications.

A single-cell morpho-transcriptomic map of brassinosteroid action in the Arabidopsis root

The effects of brassinosteroid signaling on shoot and root development have been characterized in great detail but a simple consistent positive or negative impact on a basic cellular parameter was not identified.In this study,we combined digital 3D single-cell shape analysis and single-cell mRNA sequencing to charac-terize root meristems and mature root segments of brassinosteroid-blind mutants and wild type.The resul-tant datasets demonstrate that brassinosteroid signaling affects neither cell volume nor cell proliferation capacity.Instead,brassinosteroid signaling is essential for the precise orientation of cell division planes and the extent and timing of anisotropic cell expansion.Moreover,we found that the cell-aligning effects of brassinosteroid signaling can propagate to normalize the anatomy of both adjacent and distant brassinosteroid-blind cells through non-cell-autonomous functions,which are sufficient to restore growth vigor.Finally,single-cell transcriptome data discern directly brassinosteroid-responsive genes from genes that can react non-cell-autonomously and highlight arabinogalactans as sentinels of brassinosteroid-dependent anisotropic cell expansion.