T-type calcium channel trigger p21ras signaling pathway to ERK in Cav3.1-expressed HEK293 cells.
We constructed a new cell line which stably expressed Cav3.1 and Kir2.1 subunits in HEK293 cells (HEK293/Cav3.1/Kir2.1) in order to investigate the unknown cellular signaling pathways of T-type voltage-dependent calcium channels. The new cell line has a stable resting membrane potential and can activate T-type Ca(2+) channels by KCl-mediated depolarization. We showed that Cav3.1 activation resulted in the level of p21(ras)-GTP in the cells being rapidly decreased during the first 2 min, and then recovering between 2 min and 15 min. The kinetics of ERK activation following Cav3.1 stimulation was also investigated. ERK activation was decreased from 2 min to 5 min after KCl stimulation, which means that Cav3.1 activation reduced ERK activity in the very early stages of activation. In addition, similar results for Cav3.1 activation were also shown in the case of Sos1, Grb2, and Shc, which means that Cav3.1 activation triggers p21(ras) and that this signal is transferred to ERK by Sos1, Grb2, and Shc.
Choi
Juhyun
J
Biomedical Research Center, Korea Institute of Science and Technology, Seoul, Korea.
Park
Jong-Hwa
JH
Kwon
Oh Yeun
OY
Kim
Sunoh
S
Chung
Ji Hyung
JH
Lim
Dae Sik
DS
Kim
Key Sun
KS
Rhim
Hyewhon
H
Han
Ye Sun
YS
D015153:Blotting, Western / Q000379:methods; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D020747:Calcium Channels, T-Type / Q000378:metabolism*; D002460:Cell Line; D003001:Cloning, Molecular / Q000379:methods; D004347:Drug Interactions; D004789:Enzyme Activation / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D047468:Immunoprecipitation / Q000379:methods; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D020748:Mibefradil / Q000494:pharmacology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D015689:Oncogene Protein p21(ras) / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D024661:Potassium Channels, Inwardly Rectifying / Q000378:metabolism; D011189:Potassium Chloride / Q000494:pharmacology; D015398:Signal Transduction / Q000502:physiology*; D013997:Time Factors; D018909:src Homology Domains / Q000502:physiology
C121855:CACNA1G protein, human; D002121:Calcium Channel Blockers; D020747:Calcium Channels, T-Type; C489461:Kir2.1 channel; D024661:Potassium Channels, Inwardly Rectifying; D020748:Mibefradil; D011189:Potassium Chloride; D020928:Mitogen-Activated Protein Kinases; D015689:Oncogene Protein p21(ras); D002118:Calcium