No abstract

Members of the microRNA (miR)-30 family have been reported to promote adipogenesis and inhibit osteogenesis, yet their role in the regulation of thermogenesis remains unknown. In this study, we show that miR-30b/c concentrations are greatly increased during adipocyte differentiation and are stimulated by cold exposure or the β-adrenergic receptor activator. Overexpression and knockdown of miR-30b and -30c induced and suppressed, respectively, the expression of thermogenic genes such as UCP1 and Cidea in brown adipocytes. Forced expression of miR-30b/c also significantly increased thermogenic gene expression and mitochondrial respiration in primary adipocytes derived from subcutaneous white adipose tissue, demonstrating a promoting effect of miRNAs on the development of beige fat. In addition, knockdown of miR-30b/c repressed UCP1 expression in brown adipose tissue in vivo. miR-30b/c targets the 3′-untranslated region of the receptor-interacting protein 140 (RIP140), and overexpression of miR-30b/c significantly reduced RIP140 expression. Consistent with RIP140 as a target of miR-30b/c in regulating thermogenic gene expression, overexpression of RIP140 greatly suppressed the promoting effect of miR-30b/c on the expression of UCP1 and Cidea in brown adipocytes. Taken together, the data from our study identify miR-30b/c as a key regulator of thermogenesis and uncover a new mechanism underlying the regulation of brown adipose tissue function and the development of beige fat.

BackgroundPlant WRKY transcription factors play pivotal roles in diverse biological processes but most notably in plant defense response to pathogens. Sheath blight represents one of the predominant diseases in rice. However, our knowledge about the functions of WRKY proteins in rice defense against sheath blight is rather limited.ResultsHere we demonstrate that the expression of Oryza sativa WRKY80 gene (OsWRKY80) is rapidly and strongly induced upon infection of Rhizoctonia solani, the causal agent of rice sheath blight disease. OsWRKY80 expression is also induced by exogenous jasmonic acid (JA) and ethylene (ET), but not by salicylic acid (SA). OsWRKY80-GFP is localized in the nuclei of onion epidermal cells in a transient expression assay. Consistently, OsWRKY80 exhibits transcriptional activation activity in a GAL4 assay in yeast cells. Overexpression of OsWRKY80 in rice plants significantly enhanced disease resistance to R. solani, concomitant with elevated expression of OsWRKY4, another positive regulator in rice defense against R. solani. Suppression of OsWRKY80 by RNA interference (RNAi), on the other hand, compromised disease resistance to R. solani. Results of yeast one-hybrid assay and transient expression assay in tobacco cells have revealed that OsWRKY80 specifically binds to the promoter regions of OsWRKY4, which contain W-box (TTGAC[C/T]) or W-box like (TGAC[C/T]) cis-elements.ConclusionsWe propose that OsWRKY80 functions upstream of OsWRKY4 as an important positive regulatory circuit that is implicated in rice defense response to sheath blight pathogen R. solani.Electronic supplementary materialThe online version of this article (doi:10.1186/s12284-016-0137-y) contains supplementary material, which is available to authorized users.

No abstract

No abstract

No abstract

The transport of LDL-derived cholesterol from lysosomes to peroxisomes is mediated by membrane contacts, which are facilitated by the lysosomal protein synaptotagmin VII and the peroxisomal lipid phosphatidylinositol 4, 5-bisphosphate (PI(4,5)P 2 ). Here, we used RNA interference to search for regulators of PI(4,5)P 2 and to study the effects of altered PI(4,5)P 2 homeostasis on cholesterol transport. We found that knockdown of phosphatidylinositol 5-phosphate 4-kinase type-2 alpha (PIP4K2A) reduced peroxisomal PI(4,5)P 2 levels, decreased lysosome-peroxisome membrane contacts, and increased accumulation of lysosomal cholesterol in human SV-589 fibroblasts. Forced expression of peroxisome-localized, kinase-active PIP4K2A in the knockdown cells reduced cholesterol accumulation, and in vitro addition of recombinant PIP4K2A restored membrane contacts.These results suggest that PIP4K2A plays a critical role in intracellular cholesterol transport by up-regulating PI(4,5)P 2 in the peroxisome membrane. Further research into PIP4K2A activity may inform future therapeutic interventions for managing lysosomal storage disorders.

SummaryAbscisic acid (ABA) regulates plant adaptive responses to various environmental stresses, while Lascorbic acid (AsA) that is also named vitamin C is an important antioxidant and involves in plant stress tolerance and the immune system in domestic animals. Transgenic tobacco (Nicotiana tabacum L.) and stylo [Stylosanthes guianensis (Aublet) Swartz], a forage legume, plants coexpressing stylo 9-cis-epoxycarotenoid dioxygenase (SgNCED1) and yeast D-arabinono-1,4-lactone oxidase (ALO) genes were generated in this study, and tolerance to drought and chilling was analysed in comparison with transgenic tobacco overexpressing SgNCED1 or ALO and the wild-type plants. Compared to the SgNCED1 or ALO transgenic plants, in which only ABA or AsA levels were increased, both ABA and AsA levels were increased in transgenic tobacco and stylo plants co-expressing SgNCED1 and ALO genes. Compared to the wild type, an enhanced drought tolerance was observed in SgNCED1 transgenic tobacco plants with induced expression of drought-responsive genes, but not in ALO plants, while an enhanced chilling tolerance was observed in ALO transgenic tobaccos with induced expression of cold-responsive genes, but not in SgNCED1 plants. Co-expression of SgNCED1 and ALO genes resulted in elevated tolerance to both drought and chilling in transgenic tobacco and stylo plants with induced expression of both drought and cold-responsive genes. Our result suggests that co-expression of SgNCED1 and ALO genes is an effective way for use in forage plant improvement for increased tolerance to drought and chilling and nutrition quality.