Neurotransmitter release and hormonal secretion are highly regulated processes culminating in the calcium-dependent fusion of secretory vesicles with the plasma membrane. Here, we have identified a role for phosphatidylinositol 3-kinase C2alpha (PI3K-C2alpha) and its main catalytic product, PtdIns3P, in regulated exocytosis. In neuroendocrine cells, PI3K-C2alpha is present on a subpopulation of mature secretory granules. Impairment of PI3K-C2alpha function specifically inhibits the ATP-dependent priming phase of exocytosis. Overexpression of wild-type PI3K-C2alpha enhanced secretion, whereas transfection of PC12 cells with a catalytically inactive PI3K-C2alpha mutant or a 2xFYVE domain sequestering PtdIns3P abolished secretion. Based on these results, we propose that production of PtdIns3P by PI3K-C2alpha is required for acquisition of fusion competence in neurosecretion.
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http://dx.doi.org/10.1091/mbc.e05-02-0171 | DOI Listing |
Open Life Sci
December 2024
Department of Children's Center, Beijing Luhe Hospital Affiliated to Capital Medical University, Beijing, 101149, China.
This study aimed to investigate the differential expression of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in relation to the Toll-like receptor (TLR)/nuclear factor κB (NF-κB) signaling pathway in an obese rat model. A total of 200 8-week-old male Wistar rats were randomly assigned to a control group (Ctrl, = 40) and an observation group (Obs, = 160), with obesity induced through a high-fat diet. Following modeling, the Obs group was further divided into a model group, a PI3K/AKT inhibition group, a TLR/NF-κB inhibition group, and a combined PI3K/AKT + TLR/NF-κB inhibition group, with 40 rats in each.
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2024
Department of Endocrinology and Metabolism, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, People's Republic of China; The Second Clinical Medical College, Lanzhou University, Lanzhou, People's Republic of China. Electronic address:
Previous studies have shown that nickel sulfate (NiSO) increases autophagy in thyroid cells and tissues. As an important organ of the endocrine system, the pancreas not only contributes to the exocrine function of digestion but also has the endocrine function of regulating blood sugar. However, it remains unknown whether NiSO increases pancreatic autophagy.
View Article and Find Full Text PDFJ Biochem Mol Toxicol
January 2025
Department of Neurosurgery, Jingjiang People's Hospital, Jingjiang, China.
Subarachnoid hemorrhage (SAH) is a specific type of stroke. Dihydroquercetin (DHQ), a flavonoid, is known for its various pharmacological properties. This study aimed to explore the roles and mechanisms of DHQ in influencing the progression of SAH.
View Article and Find Full Text PDFAnn Surg Oncol
January 2025
Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The Jikei University School of Medicine, Tokyo, Japan.
Background: AT-rich interaction domain 4B (ARID4B) is a transcriptional activator that regulates the phosphatidylinositol 3-kinase (PI3K)/AKT pathway in prostate cancer. However, the role of ARID4B in hepatocellular carcinoma (HCC) has remained unclear.
Methods: This study included 162 patients who had undergone primary hepatic resection for HCC between 2008 and 2019.
Hum Cell
January 2025
Department of Gastrointestinal and Colorectal Surgery, China-Japan Union Hospital of Jilin University, No. 126 Sendai Street, Nanguan District, Changchun, 130031, China.
Imatinib resistance is a major obstacle to the successful treatment of gastrointestinal stromal tumors (GIST). Long non-coding RNAs (LncRNAs) have been identified as important regulatory factors in chemotherapy resistance. This study aimed to identify key lncRNAs involved in imatinib resistance of GISTs.
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