title: Transcription factor NF-κB regulates expression of pore-forming Ca2+ channel unit, Orai1, and its activator, STIM1, to control Ca2+ entry and affect cellular functions.
abstract: The serum and glucocorticoid-inducible kinase SGK1 increases the activity of Orai1, the pore forming unit of store-operated Ca(2+) entry, and thus influences Ca(2+)-dependent cellular functions such as migration. SGK1 further regulates transcription factor nuclear factor κB (NF-κB). This study explored whether SGK1 influences transcription of Orai1 and/or STIM1, the Orai1-activating Ca(2+) sensor. Orai1 and STIM1 transcript levels were decreased in mast cells from SGK1 knock-out mice and increased in HEK293 cells transfected with active (S422D)SGK1 but not with inactive (K127N)SGK1 or in (S422D)SGK1-transfected cells treated with the NF-κB inhibitor Wogonin (100 μm). Treatment with the stem cell factor enhanced transcript levels of STIM1 and Orai1 in sgk1(+/+) but not in sgk1(-/-) mast cells and not in sgk1(+/+) cells treated with Wogonin. Orai1 and STIM1 transcript levels were further increased in sgk1(+/+) and sgk1(-/-) mast cells by transfection with active NF-κB subunit p65 as well as in HEK293 cells by transfection with NF-κB subunits p65/p50 or p65/p52. They were decreased by silencing of NF-κB subunits p65, p50, or p52 or by NF-κB inhibitor Wogonin (100 μm). Luciferase assay and chromatin immunoprecipitation defined NF-κB-binding sites in promoter regions accounting for NF-κB sensitive genomic regulation of STIM1 and Orai1. Store-operated Ca(2+) entry was similarly increased by overexpression of p65/p50 or p65/p52 and decreased by treatment with Wogonin. Transfection of HEK293 cells with p65/p50 or p65/p52 further augmented migration. The present observations reveal powerful genomic regulation of Orai1/STIM1 by SGK1-dependent NF-κB signaling.
authors: Department of Physiology, University of Tübingen, Gmelinstrasse 5, D-72076 Tübingen, Germany.
authors: Anja
authors: A
authors: Eylenstein
authors: Sebastian
authors: S
authors: Schmidt
authors: Shuchen
authors: S
authors: Gu
authors: Wenting
authors: W
authors: Yang
authors: Evi
authors: E
authors: Schmid
authors: Eva-Maria
authors: EM
authors: Schmidt
authors: Ioana
authors: I
authors: Alesutan
authors: Kalina
authors: K
authors: Szteyn
authors: Ivonne
authors: I
authors: Regel
authors: Ekaterina
authors: E
authors: Shumilina
authors: Florian
authors: F
authors: Lang
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000096:biosynthesis* / Q000235:genetics; D044950:Flavanones / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D057809:HEK293 Cells; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics / Q000378:metabolism; D008407:Mast Cells / Q000166:cytology / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D020125:Mutation, Missense; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D000071740:ORAI1 Protein; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D020218:Response Elements / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D000071737:Stromal Interaction Molecule 1; D000099184:Serum-Glucocorticoid Regulated Kinases
chemical_list: D002118:Calcium; D015220:Calcium Channels; D044950:Flavanones; D017874:Immediate-Early Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D016328:NF-kappa B; D009363:Neoplasm Proteins; D000071740:ORAI1 Protein; D017346:Protein Serine-Threonine Kinases; D000071737:Stromal Interaction Molecule 1; D000099184:Serum-Glucocorticoid Regulated Kinases; C510746:ORAI1 protein, human; C520430:Orai1 protein, mouse; C103530:STIM1 protein, human; C100757:Stim1 protein, mouse; C085514:wogonin