COLLABORATION IN BASIC SCIENCE AND ENGINEERING (COBASE)

Noriaki Ikemoto hosted Nikolai Vekshin of the Institute of Cell Biophysics, Pushchino, Russia for two weeks in January 2000. The aim of the visit was to discuss the issues and carry out preliminary experiments required for the development of an international collaboration project on the physical states of Ca2+ ATPase during the relaxation process of muscle. During Vekshin’s visit, Ikemoto and he were able to develop two future proposals. The first proposal focuses on processes within the Ca2+ ATPase during the Ca2+ re-uptake phase of contraction-relaxation coupling. Ikemoto’s laboratory has extensive experience in this area and will follow the dynamic changes in enzyme activity during the release/re-uptake period. Vekshin's laboratory has developed various sophisticated fluorescence techniques for measurement of the conformational state. Each laboratory will be using a different approach to reveal the dynamic changes occurring in the sarcoplasmic reticulum Ca2+ ATPase moiety as a function of the time after the induction of Ca2+ release. The second proposal deals with the mechanisms by which the sarcoplasmic reticulum Ca2+ ATPase is controlled during the realization phase. These mechanisms will be tested by using several fluorescent probes and techniques developed in Vekshin's laboratory.