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Sirtuin 5 (SIRT5) plays an important role in the maintenance of lipid metabolism and in white adipose tissue browning. In this study, we established a mouse model for diet-induced obesity and the browning of white fat; combined with gene expression intervention, transcriptome sequencing, and cell molecular biology methods, the regulation and molecular mechanisms of SIRT5 on fat deposition and beige fat formation were studied. The results showed that the loss of SIRT5 in obese mice exacerbated white adipose tissue deposition and metabolic inflexibility. Furthermore, the deletion of SIRT5 in a white-fat-browning mouse increased the succinylation of uncoupling protein 1 (UCP1), resulting in a loss of the beiging capacity of the subcutaneous white adipose tissue and impaired cold tolerance. Mechanistically, the inhibition of SIRT5 results in impaired CCAAT/enhancer binding protein beta (C/EBPβ) expression in brown adipocytes, which in turn reduces the UCP1 transcriptional pathway. Thus, the transcription of UCP1 mediated by the SIRT5-C/EBPβ axis is critical in regulating energy balance and obesity-related metabolism. [ABSTRACT FROM AUTHOR]

PYR/PYL/RCAR proteins are abscisic acid (ABA) receptors that play a crucial role in plant responses to abiotic stresses. However, there have been no research reports on potato PYL so far. In this study, a potato PYL gene named StPYL16 was identified based on transcriptome data under drought stress. Molecular characteristics analysis revealed that the StPYL16 protein possesses an extremely conserved PYL family domain. The tissue expression results indicated that the StPYL16 is predominantly expressed at high levels in the underground parts, particularly in tubers. Abiotic stress response showed that StPYL16 has a significant response to drought treatment. Further research on the promoter showed that drought stress could enhance the activation activity of the StPYL16 promoter on the reporter gene. Then, transient and stable expression of StPYL16 in tobacco enhanced the drought resistance of transgenic plants, resulting in improved plant height, stem thickness, and root development. In addition, compared with wild-type plants, StPYL16 transgenic tobacco exhibited lower malondialdehyde (MDA) content, higher proline accumulation, and stronger superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities. Meanwhile, StPYL16 also up-regulated the expression levels of stress-related genes (NtSOD, NtCAT, NtPOD, NtRD29A, NtLEA5, and NtP5CS) in transgenic plants under drought treatment. These findings indicated that the StPYL16 gene plays a positive regulatory role in potato responses to drought stress. [ABSTRACT FROM AUTHOR]

Adenosine kinase (ADK) is a key enzyme widely distributed in plants, playing an important role in maintaining cellular energy homeostasis and regulating plant growth, development, and responses to environmental stresses. However, research on ADK genes in cotton (Gossypium hirsutum), an economically significant crop, has been limited. This study identified 92 ADK genes from four cotton species (G. arboreum, G. raimondii, G. hirsutum, and G. barbadense) using HMMER and Local BLASTP methods and classified them into six groups. Chromosomal localization revealed a random distribution of ADK genes in G. hirsutum, with 13 genes located on the At subgenome and 14 genes on the Dt subgenome. Gene structure analysis showed consistency in exon–intron organization within subgroups, while conserved motif analysis identified subgroup-specific motifs, indicating functional diversity. Synteny and collinearity mapping analysis revealed that the primary expansion mechanisms of the ADK gene family in cotton are polyploidy and segmental duplication. Cis-regulatory elements in GhADK promoters were classified into light response, hormone response, developmental regulation, and stress response. We also analyzed the expression patterns of GhADK genes under a low temperature (4 °C) and drought conditions. Most GhADK genes responded to cold stress with different expression patterns, indicating their roles in rapid response and long-term cold adaptation. Under drought stress, expression patterns varied, with some genes showing sustained high expression levels. The qRT-PCR validation of transcriptomic data confirmed the stress-induced expression patterns of selected GhADK genes. Functional analysis through the VIGS silencing of GhADK25 demonstrated its importance in cold and drought stress responses, with silencing resulting in poor growth under stress, highlighting its significance in stress tolerance. This study provides a basis for further understanding the evolutionary relationships and functions of the cotton ADK gene family. [ABSTRACT FROM AUTHOR]

Perilipin5 (Plin5) is a scaffold protein that plays an important role in lipid droplets (LD) formation, but the regulatory effect of leptin on it is unclear. Our study aimed to explore the underlying mechanisms by which leptin reduces the N6-methyladenosine (m6A) methylation of Plin5 through fat mass and obesity associated genes (FTO) and regulates the lipolysis. To this end, 24 Landrace male piglets (7.73 ± 0.38 kg) were randomly sorted into two groups, either a control group (Control, n = 12) or a 1 mg/kg leptin recombinant protein treatment group (Leptin, n = 12). After 4 weeks of treatment, the results showed that leptin treatment group had lower body weight, body fat percentage and blood lipid levels, but the levels of Plin5 mRNA and protein increased significantly in adipose tissue (p < 0.05). Leptin promotes the up-regulation of FTO expression level in vitro, which in turn leads to the decrease of Plin5 M6A methylation (p < 0.05). In in vitro porcine adipocytes, overexpression of FTO aggravated the decrease of M6A methylation and increased the expression of Plin5 protein, while the interference fragment of FTO reversed the decrease of m6A methylation (p < 0.05). Finally, the overexpression in vitro of Plin5 significantly reduces the size of LD, promotes the metabolism of triglycerides and the operation of the mitochondrial respiratory chain, and increases thermogenesis. This study clarified that leptin can regulate Plin5 M6A methylation by promoting FTO to affect the lipid metabolism and energy consumption, providing a theoretical basis for treating diseases related to obesity. [ABSTRACT FROM AUTHOR]

The extracellular matrix (ECM) is a highly dynamic structural network and plays an essential role in cell behavior and regulation during metabolic homeostasis and obesity progression. Abnormal ECM remodeling impairs adipocyte plasticity required for diverse cellular functions. Collagen XV (ColXV) is a proteoglycan localized to the outermost layer of basement membranes (BMs) and forms a bridge between the BMs and the fibrillar collagen matrix. Nevertheless, how ColXV affects ECM composition and the reason for subsequent adipocyte apoptosis is still unclear. This report found, through RNA-seq data, that ColXV is linked to cell growth and ECM remodeling. Findings show that, in response to excessive expression of extracellular ColXV, the AMPK/mTORC1 pathway is strongly activated and triggers a cascade of mitochondrial apoptosis. This is the first study to make use of ECM three-dimensional reconstruction, based on decellularization in the adipose tissues and the study reveals that ColXV is an activation factor that alters ECM remodeling in adipose tissues. It was also demonstrated that the fibroblast growth factor 2 (FGF2)/fibroblast growth factor receptor 1 (FGFR1) axis involved in ECM remodeling is suppressed by ColXV due to reduction of FGF2 translocation to FGFR1. Furthermore, ColXV induced remodeling of ECM preceding apoptosis and continued to induce apoptosis in adipocytes. Collectively, our findings establish ColXV as a basement membrane collagen with homology to ColXVIII, indicating that it is one of the positive regulators for inducing ECM remodeling and further promoting adipocyte apoptosis. [ABSTRACT FROM AUTHOR]