Abstract
Activity of a Ca 2+ -translocating ATPase which functions as a Ca 2+ -pump was found to be associated with a highly purified plasma membrane fraction of cultured carrot cells. Different classes of calmodulin antagonists — trifluoperazine and W-7 — appreciably inhibited ATP-driven uptake of Ca 2+ into the sealed vesicles of the membrane. The incorporation of Ca 2+ was also markedly inhibited in the presence of anti-calmodulin IgG. This translocating activity was significantly decreased when the vesicles were washed with EGTA-containing buffer; however, it was restored to almost the control level upon the addition of exogenous calmodulin. These results suggest that the Ca 2+ -pumping ATPase at the plasma membrane of cultured carrot cells is regulated by calmodulin, and the modulator protein associates with the enzyme in a Ca 2+ -dependent manner.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
