Obligatory role of Src kinase in the signaling mechanism for TRPC3 cation channels.
Members of the canonical transient receptor potential (TRPC) subfamily of cation channels are candidates for capacitative and non-capacitative Ca2+ entry channels. When ectopically expressed in cell lines, TRPC3 can be activated by phospholipase C-mediated generation of diacylglycerol or by addition of synthetic diacylglycerols, independently of Ca2+ store depletion. Apart from this mode of regulation, little is known about other receptor-dependent signaling events that modulate TRPC3 activity. In the present study the role of tyrosine kinases in receptor- and diacylglycerol-dependent activation of TRPC3 was investigated. In HEK293 cells stably expressing TRPC3, pharmacological inhibition of tyrosine kinases, and specifically of Src kinases, abolished activation of TRPC3 by muscarinic receptor stimulation and by diacylglycerol. Channel regulation was lost following expression of a dominant-negative mutant of Src, or when TRPC3 was expressed in an Src-deficient cell line. In both instances, wild-type Src restored TRPC3 regulation. We conclude that Src plays an obligatory role in the mechanism for receptor and diacylglycerol activation of TRPC3.
Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709, USA. vazquez@niehs.nih.gov
Guillermo
G
Vazquez
Barbara J
BJ
Wedel
Brian T
BT
Kawasaki
Gary St John
GS
Bird
James W
JW
Putney
D015153:Blotting, Western; D002118:Calcium / Q000737:chemistry; D002460:Cell Line; D004075:Diglycerides / Q000378:metabolism; D004789:Enzyme Activation; D005786:Gene Expression Regulation; D005799:Genes, Dominant; D006801:Humans; D007473:Ion Channels / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D051966:Phospholipase C gamma; D010766:Phosphorylation; D011233:Precipitin Tests; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051076:Proto-Oncogene Proteins c-fyn; D051575:Proto-Oncogene Proteins c-yes; D029589:Seminal Plasma Proteins / Q000378:metabolism; D015398:Signal Transduction; D050052:TRPC Cation Channels; D013997:Time Factors; D014162:Transfection; D010738:Type C Phospholipases / Q000378:metabolism; D014443:Tyrosine / Q000378:metabolism; D019061:src-Family Kinases / Q000378:metabolism / Q000502:physiology*
D004075:Diglycerides; D007473:Ion Channels; D011518:Proto-Oncogene Proteins; D029589:Seminal Plasma Proteins; D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases; C494957:FYN protein, human; D051076:Proto-Oncogene Proteins c-fyn; D051575:Proto-Oncogene Proteins c-yes; C489834:YES1 protein, human; D019061:src-Family Kinases; D010738:Type C Phospholipases; D051966:Phospholipase C gamma; D002118:Calcium