TY - JOUR
T1 - Differential PI(4,5)P 2 sensitivities of TRPC4, C5 homomeric and TRPC1/4, C1/5 heteromeric channels
AU - Ko, Juyeon
AU - Myeong, Jongyun
AU - Shin, Young Cheul
AU - So, Insuk
N1 - Publisher Copyright:
© 2019, The Author(s).
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Transient receptor potential canonical (TRPC) 4 and TRPC5 channels are modulated by the Gα q -PLC pathway. Since phosphatidylinositol 4,5-bisphosphate (PI(4,5)P 2 ) maintains TRPC4 and TRPC5 channel function, the Gα q -PLC pathway inhibits channel activity by depleting PI(4,5)P 2 . Here we investigated the difference in PI(4,5)P 2 sensitivity between homomeric and heteromeric TRPC channels. First, by using a Danio rerio voltage-sensing phosphatase (DrVSP), we show that PI(4,5)P 2 dephosphorylation robustly inhibits TRPC4α, TRPC4β, and TRPC5 homotetramer currents and also TRPC1/4α, TRPC1/4β, and TRPC1/5 heterotetramer currents. Secondly, sensitivity of channels to PI(4,5)P 2 dephosphorylation was suggested through the usage of FRET in combination with patch clamping. The sensitivity increased in the sequence TRPC4β < TRPC4α < TRPC5 in homotetramers, whereas when forming heterotetramers with TRPC1, the sensitivity was approximately equal between the channels. Thirdly, we determined putative PI(4,5)P 2 binding sites based on a TRPC4 prediction model. By neutralization of basic residues, we identified putative PI(4,5)P 2 binding sites because the mutations reduced FRET to a PI(4,5)P 2 sensor and reduced the current amplitude. Therefore, one functional TRPC4 has 8 pockets with the two main binding regions; K419, K664/R511, K518, H630. We conclude that TRPC1 channel function as a regulator in setting PI(4,5)P 2 affinity for TRPC4 and TRPC5 that changes PI(4,5)P 2 sensitivity.
AB - Transient receptor potential canonical (TRPC) 4 and TRPC5 channels are modulated by the Gα q -PLC pathway. Since phosphatidylinositol 4,5-bisphosphate (PI(4,5)P 2 ) maintains TRPC4 and TRPC5 channel function, the Gα q -PLC pathway inhibits channel activity by depleting PI(4,5)P 2 . Here we investigated the difference in PI(4,5)P 2 sensitivity between homomeric and heteromeric TRPC channels. First, by using a Danio rerio voltage-sensing phosphatase (DrVSP), we show that PI(4,5)P 2 dephosphorylation robustly inhibits TRPC4α, TRPC4β, and TRPC5 homotetramer currents and also TRPC1/4α, TRPC1/4β, and TRPC1/5 heterotetramer currents. Secondly, sensitivity of channels to PI(4,5)P 2 dephosphorylation was suggested through the usage of FRET in combination with patch clamping. The sensitivity increased in the sequence TRPC4β < TRPC4α < TRPC5 in homotetramers, whereas when forming heterotetramers with TRPC1, the sensitivity was approximately equal between the channels. Thirdly, we determined putative PI(4,5)P 2 binding sites based on a TRPC4 prediction model. By neutralization of basic residues, we identified putative PI(4,5)P 2 binding sites because the mutations reduced FRET to a PI(4,5)P 2 sensor and reduced the current amplitude. Therefore, one functional TRPC4 has 8 pockets with the two main binding regions; K419, K664/R511, K518, H630. We conclude that TRPC1 channel function as a regulator in setting PI(4,5)P 2 affinity for TRPC4 and TRPC5 that changes PI(4,5)P 2 sensitivity.
UR - http://www.scopus.com/inward/record.url?scp=85061476067&partnerID=8YFLogxK
U2 - 10.1038/s41598-018-38443-0
DO - 10.1038/s41598-018-38443-0
M3 - Article
C2 - 30755645
AN - SCOPUS:85061476067
SN - 2045-2322
VL - 9
JO - Scientific reports
JF - Scientific reports
IS - 1
M1 - 1849
ER -