Pancreatic duodenal homeobox-1 (Pdx1) is a transcription factor, and its phosphorylation is thought to be essential for activation of insulin gene expression. This phosphorylation is related to a concomitant shift in molecular mass from 31 to 46 kDa. However, we found that Pdx1 was modified by SUMO-1 (small ubiquitin-related modifier 1) in beta-TC-6 and COS-7 cells, which were transfected with Pdx1 cDNA. This modification contributed to the increase in molecular mass of Pdx1 from 31 to 46 kDa. Additionally, sumoylated Pdx1 localized in the nucleus. The reduction of SUMO-1 protein by use of RNA interference (SUMO-iRNAs) resulted in a significant decrease in Pdx1 protein in the nucleus. A 34-kDa form of Pdx1 was detected by the cells exposed to SUMO-iRNAs in the presence of lactacystin, a proteasome inhibitor. Furthermore, the reduced nuclear sumoylated Pdx1 content was associated with significant lower transcriptional activity of the insulin gene. These findings indicate that SUMO-1 modification is associated with both the localization and stability of Pdx1 as well as its effect on insulin gene activation.
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http://dx.doi.org/10.1152/ajpendo.00390.2002 | DOI Listing |
Mol Nutr Food Res
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Research Center for Nutrition and Food Safety, Chongqing Key Laboratory of Nutrition and Health, Chongqing Medical Nutrition Research Center, Institute of Military Preventive Medicine, Third Military Medical University, Chongqing, P.R. China.
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Departments of Neuroscience and Biology, Brown University, Providence, RI 02903, USA.
Prenatal alcohol exposure (PAE) models can cause neurodevelopmental abnormalities like those observed in fetal alcohol spectrum disorder (FASD). Previous studies link experimental PAE effects in the brain to impaired signaling through insulin/IGF and Notch pathways that mediate neuronal survival, growth, migration, energy metabolism, and plasticity. Importantly, concurrent administration of peroxisome proliferator-activated receptor agonists or dietary soy prevented many aspects of FASD due to their insulin-sensitizing, anti-inflammatory, and antioxidant properties.
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Instituto de Neurociencias de Castilla y León (INCYL), Universidad de Salamanca, 37007 Salamanca, Spain.
Epilepsy is a multifaceted neurological disorder characterized by recurrent seizures and associated with molecular and immune alterations in key brain regions. The GASH/Sal (Genetic Audiogenic Seizure Hamster, Salamanca), a genetic model for audiogenic epilepsy, provides a powerful tool to study seizure mechanisms and resistance in predisposed individuals. This study investigates the proteomic and immune responses triggered by audiogenic kindling in the inferior colliculus, comparing non-responder animals exhibiting reduced seizure severity following repeated stimulation versus GASH/Sal naïve hamsters.
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Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Agriculture and Rural Affairs, National Engineering Laboratory for Animal Breeding, State Key Laboratory of Animal Biotech Breeding, Department of Animal Genetics and Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Exploring functional genes/sites and the molecular regulatory mechanisms underlying milk production traits in dairy cattle is crucial for improving the development of the dairy industry and human health. In our previous work, the gene collagen type VI alpha 1 () was found to be involved in milk fat metabolism from liver transcriptome data across various lactation periods of cows. Through the integration of Cattle QTLdb, FarmGTEx and qPCR data, the gene was found to be located within known quantitative trait loci (QTLs), adjacent to single-nucleotide polymorphisms (SNPs) associated with milk traits, and highly expressed in the mammary gland.
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MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Xin Gang Xi Road 135#, Guangzhou 510275, China.
Diabetes mellitus (DM) is a chronic metabolic disorder and one of the most significant global health burdens worldwide. Key pathophysiological mechanisms underlying its onset and associated complications include hyperglycemia-related stresses, such as oxidative stress and endoplasmic reticulum stress (ER stress). Long non-coding RNAs (lncRNAs), defined as RNA transcripts longer than 200 nucleotides and lacking protein-coding capacity, play crucial roles in various biological processes and have emerged as crucial regulators in the pathogenesis of diabetes.
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