| RRC ID |
10959
|
| Author |
Vazquez G, Wedel BJ, Trebak M, St John Bird G, Putney JW Jr.
|
| Title |
Expression level of the canonical transient receptor potential 3 (TRPC3) channel determines its mechanism of activation.
|
| Journal |
J Biol Chem
|
| Abstract |
Studies on the mechanism of activation of canonical transient receptor potential (TRPC) channels have often yielded conflicting results. In the current study, we have investigated the influence of expression level on the mode of regulation of TRPC3 channels. At relatively low levels of expression in DT40 chicken B-lymphocytes, TRPC3 was activated by the depletion of Ca2+ stores. Expression was increased by either transfecting with a 10-fold greater concentration of plasmid or transfecting with TRPC3 under control of a more efficient avian beta-actin promoter. At higher levels of expression, TRPC3 was no longer store-operated but could be activated through receptor-coupled phospholipase C. Under these expression conditions, TRPC3 was efficiently activated in DT40 cells lacking inositol 1,4,5-trisphosphate receptors. The Ca2+ store-operated channels formed upon expression of TRPC3 at limited levels were blocked by gadolinium; the receptor-activated channels formed upon expression of higher levels of TRPC3 were insensitive to gadolinium. These findings indicate that a single ion channel protein can form or contribute to the formation of channels regulated in two very distinct ways, i.e. either by phospholipase C-derived messengers or Ca2+ store-depletion. The mechanism of regulation of the channels depends on their level of expression.
|
| Volume |
278(24)
|
| Pages |
21649-54
|
| Published |
2003-6-13
|
| DOI |
10.1074/jbc.M302162200
|
| PII |
S0021-9258(20)68567-2
|
| PMID |
12686562
|
| MeSH |
Animals
B-Lymphocytes / metabolism
Calcium / metabolism
Calcium Channels / metabolism
Cell Line
Chickens
Coloring Agents / pharmacology
Fura-2 / pharmacology
Gene Expression Regulation
Humans
Inositol 1,4,5-Trisphosphate Receptors
Ion Channels / biosynthesis*
Ion Channels / metabolism*
Microscopy, Confocal
Plasmids / metabolism
Protein Binding
Receptor, Muscarinic M5
Receptors, Cytoplasmic and Nuclear / metabolism
Receptors, Muscarinic / metabolism
TRPC Cation Channels
Time Factors
Transfection
Type C Phospholipases / metabolism
|
| IF |
4.238
|
| Times Cited |
118
|
|
WOS Category
|
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
| Resource |
| Human and Animal Cells |
DT40(RCB1464)
IP3R^(-) DT40(RCB1467) |
