Phospholipase C-gamma is required for agonist-induced Ca2+ entry.
We report here that PLC-gamma isoforms are required for agonist-induced Ca2+ entry (ACE). Overexpressed wild-type PLC-gamma1 or a lipase-inactive mutant PLC-gamma1 each augmented ACE in PC12 cells, while a deletion mutant lacking the region containing the SH3 domain of PLC-gamma1 was ineffective. RNA interference to deplete either PLC-gamma1 or PLC-gamma2 in PC12 and A7r5 cells inhibited ACE. In DT40 B lymphocytes expressing only PLC-gamma2, overexpressed muscarinic M5 receptors (M5R) activated ACE. Using DT40 PLC-gamma2 knockout cells, M5R stimulation of ER Ca2+ store release was unaffected, but ACE was abolished. Normal ACE was restored by transient expression of PLC-gamma2 or a lipase-inactive PLC-gamma2 mutant. The results indicate a lipase-independent role of PLC-gamma in the physiological agonist-induced activation of Ca2+ entry.
Patterson
Randen L
RL
Department of Neuroscience, Department of Pharmacology and Molecular Sciences, Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
van Rossum
Damian B
DB
Ford
Diana L
DL
Hurt
Kenneth J
KJ
Bae
Sun Sik
SS
Suh
Pann Ghill
PG
Kurosaki
Tomohiro
T
Snyder
Solomon H
SH
Gill
Donald L
DL
D000818:Animals; D002118:Calcium; D002384:Catalysis; D002461:Cell Line, Transformed; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D016716:PC12 Cells; D051966:Phospholipase C gamma; D012330:RNA, Double-Stranded; D034741:RNA, Small Interfering; D051381:Rats; D010738:Type C Phospholipases / Q000235:genetics / Q000378:metabolism*
D007527:Isoenzymes; D012330:RNA, Double-Stranded; D034741:RNA, Small Interfering; D010738:Type C Phospholipases; D051966:Phospholipase C gamma; D002118:Calcium