The dimeric form of Ca2+-ATPase is involved in Ca2+ transport in the sarcoplasmic reticulum |
| |
Authors: | Ushimaru Makoto Fukushima Yoshihiro |
| |
Affiliation: | Department of Chemistry, Kyorin University School of Medicine, Shinkawa 6-20-2, Mitaka, Tokyo, Japan. ushimaru@kyorin-u.ac.jp |
| |
Abstract: | To identify the functional unit of Ca(2+)-ATPase in the sarcoplasmic reticulum, we assessed Ca(2+)-transport activities occurring on sarcoplasmic reticulum membranes with different combinations of active and inactive Ca(2+)-ATPase molecules. We prepared heterodimers, consisting of a native Ca(2+)-ATPase molecule and a Ca(2+)-ATPase molecule inactivated by FITC labelling, by fusing vesicles loaded with each type of Ca(2+)-ATPase. The heterodimers exhibited neither Ca(2+) transport nor ATP hydrolysis, suggesting that Ca(2+) transport by the Ca(2+)-ATPase requires an interaction between functional Ca(2+)-ATPase monomers. This finding implies that the functional unit of the Ca(2+)-ATPase is a dimer. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|