Local control of TRPV4 channels by AKAP150-targeted PKC in arterial smooth muscle.
Enviado por Manuel F Navedo el
Título | Local control of TRPV4 channels by AKAP150-targeted PKC in arterial smooth muscle. |
Publication Type | Journal Article |
Year of Publication | 2014 |
Autores | Mercado, J, Baylie, R, Navedo, MF, Yuan, C, Scott, JD, Nelson, MT, Brayden, JE, Santana, LF |
Journal | J Gen Physiol |
Volume | 143 |
Issue | 5 |
Pagination | 559-75 |
Date Published | 2014 May |
ISSN | 1540-7748 |
Abstract | Transient receptor potential vanilloid 4 (TRPV4) channels are Ca(2+)-permeable, nonselective cation channels expressed in multiple tissues, including smooth muscle. Although TRPV4 channels play a key role in regulating vascular tone, the mechanisms controlling Ca(2+) influx through these channels in arterial myocytes are poorly understood. Here, we tested the hypothesis that in arterial myocytes the anchoring protein AKAP150 and protein kinase C (PKC) play a critical role in the regulation of TRPV4 channels during angiotensin II (AngII) signaling. Super-resolution imaging revealed that TRPV4 channels are gathered into puncta of variable sizes along the sarcolemma of arterial myocytes. Recordings of Ca(2+) entry via single TRPV4 channels ("TRPV4 sparklets") suggested that basal TRPV4 sparklet activity was low. However, Ca(2+) entry during elementary TRPV4 sparklets was ∼ 100-fold greater than that during L-type CaV1.2 channel sparklets. Application of the TRPV4 channel agonist GSK1016790A or the vasoconstrictor AngII increased the activity of TRPV4 sparklets in specific regions of the cells. PKC and AKAP150 were required for AngII-induced increases in TRPV4 sparklet activity. AKAP150 and TRPV4 channel interactions were dynamic; activation of AngII signaling increased the proximity of AKAP150 and TRPV4 puncta in arterial myocytes. Furthermore, local stimulation of diacylglycerol and PKC signaling by laser activation of a light-sensitive Gq-coupled receptor (opto-α1AR) resulted in TRPV4-mediated Ca(2+) influx. We propose that AKAP150, PKC, and TRPV4 channels form dynamic subcellular signaling domains that control Ca(2+) influx into arterial myocytes. |
DOI | 10.1085/jgp.201311050 |
Alternate Journal | J. Gen. Physiol. |
PubMed ID | 24778429 |
PubMed Central ID | PMC4003184 |
Grant List | 2-P20-RR-016435-06 / RR / NCRR NIH HHS / United States GM048231 / GM / NIGMS NIH HHS / United States HL085870 / HL / NHLBI NIH HHS / United States HL098200 / HL / NHLBI NIH HHS / United States HL098243 / HL / NHLBI NIH HHS / United States HL44455 / HL / NHLBI NIH HHS / United States P01 HL095488 / HL / NHLBI NIH HHS / United States P01HL095488 / HL / NHLBI NIH HHS / United States P30 GM103498 / GM / NIGMS NIH HHS / United States R01 DK053832 / DK / NIDDK NIH HHS / United States R01 HL044455 / HL / NHLBI NIH HHS / United States R01 HL085870 / HL / NHLBI NIH HHS / United States R01 HL098243 / HL / NHLBI NIH HHS / United States R37DK053832 / DK / NIDDK NIH HHS / United States |