lncRNAs MALAT1 and LINC00657 upstream to miR-214-3p/BMP2 regulate osteogenic differentiation of human mesenchymal stem cells.

BACKGROUND: Osteogenic differentiation of human mesenchymal stem cells (hMSCs) holds significant clinical implications for patients with bone diseases. LncRNAs are an emerging group of epigenetic modulators involved in the osteogenesis of hMSCs. In this study, we explored lncRNA profiles that are upstream to the hsa-miR-214-3p/BMP2 axis in osteogenic differentiation of hMSCs. METHOD: HMSCs were induced toward osteogenesis for 14 days. Between day 1 and day 14, qRT-PCR was conducted to compare the expressions of BMP2, Runx2, hsa-miR-214-3p, and biochemical assays to compare alkaline phosphatase and Alizarin Red S activities. 145 lncRNAs, which were experimentally confirmed upstream to hsa-miR-214-3p were examined. Five significantly upregulated lncRNAs, MEG3, SNHG16, FAM83H-AS1, MALAT1 and LINC00657 were downregulated in differentiated hMSCs and their impact on osteogenic differentiation were examined. Hsa-miR-214-3p was silenced in lncRNAs-downregulated hMSCs to further examine the association between lncRNAs and hsa-miR-214-3p/BMP2 axis. RESULTS: From day 1 to day 14, hMSCs underwent significant osteogenic differentiation, and KCNQ1OT1, MEG3, SNHG16, FAM83H-AS1, MALAT1 and LINC00657 were significantly upregulated. Downregulations of MEG3, SNHG16, FAM83H-AS1, MALAT1 and LINC00657 all suppressed osteogenic differentiation. However, qRT-PCR and RIP assay demonstrated that only MALAT1 and LINC00657 acted through hsa-miR-214-3p/BMP2 to regulate osteogenic differentiation. Furthermore, silencing hsa-miR-214-3p only rescued osteogenic differentiation in MALAT1- or LINC00657- downregulated hMSCs. CONCLUSIONS: Our data strongly indicated that lncRNAs MALAT1 and LINC00657 acted through miR-214-3p/BMP2 axis to regulate osteogenic differentiation of hMSCs.

Genetic Diversity and Population Structure of Chinese Chestnut (Castanea mollissima Blume) Cultivars Revealed by GBS Resequencing.

Chinese chestnut (Castanea mollissima Bl.) is one of the earliest domesticated and cultivated fruit trees, and it is widely distributed in China. Because of the high quality of its nuts and its high resistance to abiotic and biotic stresses, Chinese chestnut could be used to improve edible chestnut varieties worldwide. However, the unclear domestication history and highly complex genetic background of Chinese chestnut have prevented the efficiency of breeding efforts. To explore the genetic diversity and structure of Chinese chestnut populations and generate new insights that could aid chestnut breeding, heterozygosity statistics, molecular variance analysis, ADMIXTURE analysis, principal component analysis, and phylogenetic analysis were conducted to analyze single nucleotide polymorphism data from 185 Chinese chestnut landraces from five geographical regions in China via genotyping by sequencing. Results showed that the genetic diversity level of the five populations from different regions was relatively high, with an observed heterozygosity of 0.2796-0.3427. The genetic diversity level of the population in the mid-western regions was the highest, while the population north of the Yellow River was the lowest. Molecular variance analysis showed that the variation among different populations was only 2.07%, while the intra-group variation reached 97.93%. The Chinese chestnut samples could be divided into two groups: a northern and southern population, separated by the Yellow River; however, some samples from the southern population were genetically closer to samples from the northern population. We speculate that this might be related to the migration of humans during the Han dynasty due to the frequent wars that took place during this period, which might have led to the introduction of chestnut to southern regions. Some samples from Shandong Province and Beijing City were outliers that did not cluster with their respective groups, and this might be caused by the special geographical, political, and economic significance of these two regions. The findings of our study showed the complex genetic relationships among Chinese chestnut landraces and the high genetic diversity of these resources.

A Review of the Stress Resistance, Molecular Breeding, Health Benefits, Potential Food Products, and Ecological Value of Castanea mollissima.

Chestnut (Castanea spp., Fagaceae family) is an economically and ecologically valuable species. The main goals of chestnut production vary among species and countries and depend on the ecological characteristics of orchards, agronomic management, and the architecture of chestnut trees. Here, we review recent research on chestnut trees, including the effects of fungal diseases (Cryphonectria parasitica and Phytophthora cinnamomi) and insect pests (Dryocosmus kuriphilus Yasumatsu), molecular markers for breeding, ecological effects, endophytic fungi, and extracts with human health benefits. We also review research on chestnut in the food science field, technological improvements, the soil and fertilizer used for chestnut production, and the postharvest biology of chestnut. We noted differences in the factors affecting chestnut production among regions, including China, the Americas, and Europe, especially in the causal agents of disease and pests. For example, there is a major difference in the resistance of chestnut to C. parasitica in Asian, European, and American countries. Our review provides new insights into the integrated disease and pest management of chestnut trees in China. We hope that this review will foster collaboration among regions and help to clarify differences in the direction of breeding efforts among countries.

[Expression profile analysis of Peptide5 and Peptide6 in Arabidopsis].

Two predicted peptide genes in Arabidopsis thaliana L., Peptide5 and Peptide6, was confirmed by RT-PCR in mRNA level. The expression profile indicated that both genes were generally expressed at different developmental stages and tissues as constitutive gene expression, and they also responded to six treatments including NaCl, PEG, MeJA (methyl jasmonate), SA (salicylic acid), cold and wound in transcription level. Analysis of the promoter sequence suggests that Peptide5 in Arabidopsis may contribute to the secondary xylem formation.