Although group IVA cytosolic phospholipase A(2) (cPLA(2)alpha) has been reported to be phosphorylated at multiple Ser residues, the mechanisms by which phosphorylation at different sites regulates cPLA(2)alpha activities are not fully understood. To explore the possibility that phosphorylation of Ser(727) modulates cellular protein-protein interactions, we measured the effect of Ser(727) mutations on the interaction of cPLA(2)alpha with a reported cPLA(2)alpha-binding protein, p11. In vitro activity assays and membrane binding measurements by surface plasmon resonance analysis showed that a heterotetramer (A2t) of p11 and annexin A2, but not p11 or annexin A2 alone, directly binds cPLA(2)alpha via Ser(727), which keeps the enzyme from binding the membrane and catalyzing the phospholipid hydrolysis. Phosphorylation of Ser(727) disrupts this inhibitory cPLA(2)alpha-A2t interaction, thereby activating cPLA(2)alpha. Subcellular translocation and activity measurements in HEK293 cells cotransfected with cPLA(2)alpha and p11 also showed that p11, in the form of A2t, inhibits cPLA(2)alpha by the same mechanism and that phosphorylation of Ser(727) activates cPLA(2)alpha by interfering with the inhibitory cPLA(2)alpha-A2t interaction. Collectively, these studies provide new insight into the regulatory mechanism of cPLA(2)alpha through Ser(727) phosphorylation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1074/jbc.M707345200 | DOI Listing |
Nan Fang Yi Ke Da Xue Xue Bao
January 2025
College of Basic Medical Sciences, Xiangnan University, Chenzhou 423000, China.
Objectives: To explore the active components that mediate the therapeutic effect of on psoriasis and their therapeutic mechanisms.
Methods: TCMSP, TCMIP, PharmMapper, Swiss Target Prediction, GeneCards, OMIM and TTD databases were searched for the compounds in and their targets and the disease targets of psoriasis. A drug-active component-target network and the protein-protein interaction network were constructed, and DAVID database was used for pathway enrichment analysis.
J Clin Endocrinol Metab
December 2024
Department of Ophthalmology, Shanghai Ninth People's Hospital, Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, and Center for Basic Medical Research and Innovation in Visual System Diseases of Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai, 200001, China.
Context: CD34+ orbital fibroblasts (OFs) play a pathogenic role in thyroid eye disease (TED). Several micro (mi)RNAs have been shown to promote TED progression.
Objective: This study aims to explore the regulatory effect of miRNAs on CD34+ OFs, to find potential therapeutic target.
Adv Sci (Weinh)
December 2024
Department of Cardiology, State Key Laboratory of Organ Failure Research, Nanfang Hospital, Southern Medical University, 1838 North Guangzhou Avenue, Guangzhou, 510515, China.
Ischemic preconditioning (IPC) therapy application to attenuate myocardial ischemia-reperfusion (MI/R) injury in clinical practice remains challenging. The secretome, derived from hypoxia-preconditioned cardiomyocytes (SHPC), potentially mimics the IPC microenvironment and facilitates IPC clinical translation. This study aims to determine whether SHPC can be a feasible alternative to IPC for attenuating MI/R injury, and to identify the functional factor of SHPC.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Basis Dis
December 2024
Department of Bioactive Molecules, Pharmacology, Gifu Pharmaceutical University, Gifu 501-1196, Japan; United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu 501-1196, Japan; Center for One Medicine Innovative Translational Research (COMIT), Division of Innovative Modality Development, Gifu University, Gifu 501-1196, Japan. Electronic address:
Prostate
February 2025
Department of Translational Medicine, Division of Urological Cancers, Lund University, Malmö, Sweden.
Background: The transcription factor Signal Transducer and Activator of Transcription 3 (STAT3) plays a role in carcinogenesis and is involved in processes, such as proliferation, differentiation, drug resistance and immunosuppression. STAT3 can be activated by phosphorylation of tyrosine at position 705 (pSTAT3) or serine at 727 (pSTAT3). High expression levels of pSTAT3 are implicated in advanced stages of prostate cancer (PCa) and are known to interact with the androgen receptor signaling pathway.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!