Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.27.5 (RNase)
 17,967 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of long-term depolarization on frog skeletal muscle Cav1.1 channels were assessed. Voltage-clamp and Western-blot experiments revealed that long-term depolarization brings about a drastic reduction in the amplitude of currents flowing through Cav1.1 channels and in the levels of the alpha1s subunit, the main subunit of muscle L-type channels. The decline of both phenomena was prevented by the action of the protease inhibitors E64 (50 microM) and leupeptin (50 microM). In contrast, long-term depolarization had no effect on beta1, the auxiliary subunit of alpha1s. The levels of mRNAs coding the alpha1s and the beta1 subunits were measured by RNase protection assays. Neither the content of the alpha1s nor the beta1 subunit mRNAs were affected by long-term depolarization, indicating that the synthesis of Cav1.1 channels remained unaffected. Taken together, our experiments suggest that the reduction in the amplitude of membrane currents and in the alpha1s subunit levels is caused by increased degradation of this subunit by a Ca2+-dependent protease.
 ...
PMID:Regulation of muscle Cav1.1 channels by long-term depolarization involves proteolysis of the alpha1s subunit. 1545 72