Coronin 1A depletion protects endothelial cells from TNFα-induced apoptosis by modulating p38β expression and activation.
Coronins are conserved actin-binding proteins that regulate various cellular processes such as migration and endocytosis. Among coronin family members, coronin 1A is highly expressed in hematopoietic lineage cells where it regulates cell homeostasis. However, the expression and function of coronin 1A in endothelial cells have not yet been elucidated. We found that coronin 1A is expressed in the human umbilical vein endothelial cell (HUVEC) and human brain microvascular endothelial cell (HBMVEC). In HUVEC depleted of coronin 1A by siRNA transfection, tumor necrosis factor α (TNFα)+cyclohexamide (CHX) treatment resulted in a decrease in the number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positive apoptotic cells. Coronin 1A depletion also resulted in the suppression of caspase 3 and poly(ADP-ribose) polymerase cleavage and a reduction in caspase 3 activity. Next, we examined TNFα-induced activation of several pro- and anti-apoptotic signaling molecules to find the target molecule of coronin 1A and found that p38 phosphorylation was enhanced by TNFα stimulation in coronin 1A-depleted HUVEC. Among the p38 isoforms, the expression of p38β was significantly upregulated after coronin 1A depletion, suggesting that the expression and phosphorylation of anti-apoptotic p38β were significantly induced in coronin 1A-depleted HUVEC. Inhibition of p38β upregulation in coronin 1A-depleted HUVEC restored the cleavage of caspase 8 and caspase 3 and induced more apoptosis than in coronin 1A-depleted HUVEC in response to TNFα+CHX. These findings suggest that coronin 1A modulates endothelial cell apoptosis by regulating p38β expression and activation.
Division of Cardiovascular and Rare Disease, Center for Biomedical Sciences, Korea National Institute of Health, Cheongju, Republic of Korea.
Geun-Young
GY
Kim
Division of Cardiovascular and Rare Disease, Center for Biomedical Sciences, Korea National Institute of Health, Cheongju, Republic of Korea.
Hanna
H
Kim
Division of Cardiovascular and Rare Disease, Center for Biomedical Sciences, Korea National Institute of Health, Cheongju, Republic of Korea.
Hyun-Joung
HJ
Lim
Division of Cardiovascular and Rare Disease, Center for Biomedical Sciences, Korea National Institute of Health, Cheongju, Republic of Korea. Electronic address: mdhypark@gmail.com.
Hyun-Young
HY
Park
D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D048290:Mitogen-Activated Protein Kinase 11 / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D054378:Acetogenins
D015107:4-Butyrolactone; D053148:Caspase 3; D053181:Caspase 8; D003513:Cycloheximide; D048290:Mitogen-Activated Protein Kinase 11; D014409:Tumor Necrosis Factor-alpha; C438920:coronin acetogenin; D054378:Acetogenins; C505407:CASP3 protein, human; C505530:CASP8 protein, human
Apoptosis; Coronin 1A; Endothelial cell; Tumor necrosis factor α; p38β