RhMED15a-like, a subunit of the Mediator complex, is involved in the drought stress response in Rosa hybrida.

BACKGROUND: Rose (Rosa hybrida) is a globally recognized ornamental plant whose growth and distribution are strongly limited by drought stress. The role of Mediator, a multiprotein complex crucial for RNA polymerase II-driven transcription, has been elucidated in drought stress responses in plants. However, its physiological function and regulatory mechanism in horticultural crop species remain elusive. RESULTS: In this study, we identified a Tail module subunit of Mediator, RhMED15a-like, in rose. Drought stress, as well as treatment with methyl jasmonate (MeJA) and abscisic acid (ABA), significantly suppressed the transcript level of RhMED15a-like. Overexpressing RhMED15a-like markedly bolstered the osmotic stress tolerance of Arabidopsis, as evidenced by increased germination rate, root length, and fresh weight. In contrast, the silencing of RhMED15a-like through virus induced gene silencing in rose resulted in elevated malondialdehyde accumulation, exacerbated leaf wilting, reduced survival rate, and downregulated expression of drought-responsive genes during drought stress. Additionally, using RNA-seq, we identified 972 differentially expressed genes (DEGs) between tobacco rattle virus (TRV)-RhMED15a-like plants and TRV controls. Gene Ontology (GO) analysis revealed that some DEGs were predominantly associated with terms related to the oxidative stress response, such as 'response to reactive oxygen species' and 'peroxisome'. Furthermore, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment highlighted pathways related to 'plant hormone signal transduction', in which the majority of DEGs in the jasmonate (JA) and ABA signalling pathways were induced in TRV-RhMED15a-like plants. CONCLUSION: Our findings underscore the pivotal role of the Mediator subunit RhMED15a-like in the ability of rose to withstand drought stress, probably by controlling the transcript levels of drought-responsive genes and signalling pathway elements of stress-related hormones, providing a solid foundation for future research into the molecular mechanisms underlying drought tolerance in rose.

ERF54 regulates cold tolerance in Rosa multiflora through DREB/COR signalling pathways.

Ethylene-responsive factors (ERFs) participate in a wide range of physiological and biological processes. However, many of the functions of ERFs in cold stress responses remain unclear. We, therefore, characterised the cold responses of RmERF54 in Rosa multiflora, a rose-related cold-tolerant species. Overexpression of RmERF54, which is a nuclear transcription factor, increases the cold resistance of transgenic tobacco and rose somatic embryos. In contrast, virus-induced gene silencing (VIGS) of RmERF54 increased cold susceptibility of R. multiflora. The overexpression of RmERF54 resulted in extensive transcriptional reprogramming of stress response and antioxidant enzyme systems. Of these, the levels of transcripts encoding the PODP7 peroxidase and the cold-related COR47 protein showed the largest increases in the somatic embryos with ectopic expression of RmERF54. RmERF54 binds to the promoters of the RmPODP7 and RmCOR47 genes and activates expression. RmERF54-overexpressing lines had higher antioxidant enzyme activities and considerably lower levels of reactive oxygen species. Opposite effects on these parameters were observed in the VIGS plants. RmERF54 was identified as a target of Dehydration-Responsive-Element-Binding factor (RmDREB1E). Taken together, provide new information concerning the molecular mechanisms by which RmERF54 regulates cold tolerance.

Feeder cells treated with ethanol can be used to maintain self-renewal and pluripotency of human pluripotent stem cells.

Feeder cells play an important role in the culture of human pluripotent stem cells (hPSCs) in vitro. Previously, we used methanol as a fixative to prepare feeder cells for the cultivation of pluripotent stem cells (PSCs), and this method could maintain the self-renewal and pluripotency of PSCs. However, methanol is toxic, and so here we examined whether ethanol could be used to prepare feeder cells as a fixative for hPSC culturing. Primed, naïve, and extended human embryonic stem cells and induced pluripotent stem cells can maintain self-renewal and undifferentiated potential on feeder cells treated with ethanol for an extended period. RNA sequencing analysis showed that the expression of collagen-related genes in hPSCs cultured on feeder cells treated with ethanol was significantly lower as compared with hPSCs cultured on feeder cells treated with mitomycin C. Therefore, we speculate that the signaling pathway mediated by collagen-related genes may, at least in part, contribute to the maintenance of self-renewal and pluripotency of PSCs induced by feeder cells treated with chemicals.

Risk for Gestational Diabetes Mellitus and Adverse Birth Outcomes in Chinese Women with Polycystic Ovary Syndrome.

Objective. To examine the association of polycystic ovary syndrome (PCOS) in early pregnancy with gestational diabetes mellitus (GDM) and adverse birth outcomes. Methods. In this retrospective cohort study including 2389 pregnant women, the medical records of 352 women diagnosed with PCOS were evaluated. Outcomes included GDM, preterm birth, low birth weight, macrosomia, and being small and large for gestational age. Multivariable logistic regression models were used to examine the association of the risk for GDM and adverse birth outcomes with PCOS after adjusting for confounders. Results. Women previously diagnosed with PCOS had a higher risk of GDM (adjusted odds ratio [OR] 1.55, 95% confidence interval [CI]: 1.14-2.09). A strong association was seen between PCOS and preterm birth (adjusted OR 1.69, 95% CI: 1.08-2.67). On stratified analysis, the adjusted OR for GDM among women with PCOS undergoing assisted reproductive technology was 1.44 (95% CI: 1.03-1.92) and among women with PCOS who conceived spontaneously was 1.60 (1.18-2.15). No increased risk for other adverse birth outcomes was observed. Conclusions. Women with PCOS were more likely to experience GDM and preterm birth.

DhEFL2, 3 and 4, the three EARLY FLOWERING4-like genes in a Doritaenopsis hybrid regulate floral transition.

KEY MESSAGE: DhEFL2, 3 and 4 regulate the flowering of Doritaenopsis . These genes could rescue elf4-1 phenotype in Arabidopsis while its overexpression delayed flowering. Phalaenopsis are popular floral plants, and studies on orchid flowering genes could help develop off-season cultivars. Early flowering 4 (ELF4) of A. thaliana has been shown to be involved in photoperiod perception and circadian regulation. We isolated two members of the ELF4 family from Doritaenopsis hybrid (Doritaenopsis 'Tinny Tender' (Doritaenopsis Happy Smile × Happy Valentine)), namely, DhEFL2 and DhEFL3 (DhEFL4 has been previously cloned). Multiple alignment analysis of the deduced amino acid sequences of the three DhEFL homologs showed that DhEFL4 and DhEFL2 are similar with 72% identical amino acids, whereas DhEFL3 is divergent with 72% similarity with DhEFL2 and 68% similarity with DhEFL4. DhEFL3 forms a separate phylogenetic subgroup and is far away from DhEFL2 and DhEFL4. The diurnal expression patterns of DhEFL2, 3, and 4 are similar in the long-day photoperiod conditions; however, in the short-day conditions, DhEFL3 is different from DhEFL2 and 4. For the DhEFL2, 3, and 4 genes, the strongest audience expression organs are the stem, petal and bud, respectively. The ectopic expression of DhEFL2, 3, or 4 in transgenic A. thaliana plants (Ws-2 ecotype) showed novel phenotypes by late flowering and more rosette leaves. The ectopic expression of DhEFL2, 3, or 4 could complement the elf4-1 flowering time and hypocotyl length defects in transgenic A. thaliana elf4-1 mutant plants. These results strongly suggest that DhEFL2, 3, and 4 may be involved in regulation of flower formation and floral induction in Doritaenopsis.

[Optimizing of cDNA preparation for next generation sequencing].

Next generation sequencing has already been used for genomic analysis of microorganis, human being, animals, and plants. Sample preparation is prerequisite and most important for large-scale sequencing. There are two major interferences for large-scale sequencing, polyA and abundant genes' concealment for rare genes. In order to solve these problems, we used total RNA extracted from violaceae leaves to produce double stranded cDNA. DSN nuclease was used to treat the ds cDNA prior to removing the polyA. Randomly sequencing 100 clones of the treated cDNA showed that there were 94 independent clones in the treated sample, and the sequences did not contained polyA. However, only 62 independent clones were found in the untreated sample, and 15 of the sequencing files were affected by polyA. By randomly sequencing of the treated cDNA, we also found two clones encoded two interested genes. We failed to isolate these genes although the protein mass peaks of them had been found in the MALDI-TOF trace. Furthermore, we designed primers from two known genes with different expression abundances. The PCR yields were approaching similar using the treated cDNAs as templates. These results showed that, removal of the polyA and enrichment of rare genes with DSN can meet the requirements of large-scale sequencing and discovery of new genes.