PIP2 regulation of TRPC5 channel activation and desensitization

Autor: Anna Greka, Leigh D. Plant, Mehek Ningoo, Diomedes E. Logothetis
Jazyk: angličtina
Rok vydání: 2021
Předmět:
0301 basic medicine
TRPC5 channels
Models
Molecular
Phosphatidylinositol 4
5-Diphosphate
transient receptor potential channels (TRP channels)
CCh
carbachol
CIBN
cryptochrome-interacting basic-helix-loop-helix N-terminal fragment
Protein Conformation
NHERF
Na+/H+ exchanger regulatory factor
Gating
CRY2
cryptochrome 2
TRPC5
Biochemistry
OAG
1-oleoyl-2-acetyl-sn-glycerol
TIRF
total internal reflection fluorescence
03 medical and health sciences
Transient receptor potential channel
chemistry.chemical_compound
PLC
phospholipase C
Humans
Molecular Biology
Protein kinase C
Ion channel
Diacylglycerol kinase
diC8–PIP2
dioctanoyl-glycerol-PIP2
TRPC Cation Channels
030102 biochemistry & molecular biology
Phospholipase C
Chemistry
PIP-5K
phosphatidylinositol 4-phosphate 5 kinase
phosphatidylinositol 4
5-bisphosphate (PIP2)
Cell Biology
Editors' Pick
diacyl glycerol (DAG)
TRPC5
transient receptor potential canonical type 5
YFP
yellow fluorescent protein
Cell biology
phosphoinositide
PIP2
phosphatidylinositol 4
5-bisphosphate
PMA
phorbol 12-myristate-13-acetate
030104 developmental biology
HEK293 Cells
Phosphatidylinositol 4
5-bisphosphate
lipids (amino acids
peptides
and proteins)
phosphatidylinositol signaling
IP3
inositol 1
4
5-triphosphate
5’-ptaseOCRL
5’-phosphatase domain of OCRL
DAG
diacylglycerol
Research Article
Zdroj: The Journal of Biological Chemistry
ISSN: 1083-351X
0021-9258
Popis: Transient receptor potential canonical type 5 (TRPC5) ion channels are expressed in the brain and kidney and have been identified as promising therapeutic targets whose selective inhibition can protect against diseases driven by a leaky kidney filter, such as focal segmental glomerular sclerosis. TRPC5 channels are activated not only by elevated levels of extracellular Ca2+or lanthanide ions but also by G protein (Gq/11) stimulation. Phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis by phospholipase C enzymes leads to PKC-mediated phosphorylation of TRPC5 channels and their subsequent desensitization. However, the roles of PIP2 in activation and maintenance of TRPC5 channel activity via its hydrolysis product diacyl glycerol (DAG), as well as the mechanism of desensitization of TRPC5 activity by DAG-stimulated PKC activity, remain unclear. Here, we designed experiments to distinguish between the processes underlying channel activation and inhibition. Employing whole-cell patch-clamp, we used an optogenetic tool to dephosphorylate PIP2 and assess channel–PIP2 interactions influenced by activators, such as DAG, or inhibitors, such as PKC phosphorylation. Using total internal reflection microscopy, we assessed channel cell surface density. We show that PIP2 controls both the PKC-mediated inhibition and the DAG- and lanthanide-mediated activation of TRPC5 currents via control of gating rather than channel cell surface density. These mechanistic insights promise to aid in the development of more selective and precise inhibitors to block TRPC5 channel activity and illuminate new opportunities for targeted therapies for a group of chronic kidney diseases for which there is currently a great unmet need.
Databáze: OpenAIRE
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