Abstract
The effect of phorbol esters on membrane phosphorylation was examined in intact rabbit erythrocytes prelabeled with [ 32P ]orthophosphate. Tumor-promoting phorbol ester, phorbol 12-myristate 13-acetate, but not the inactive 4α-phorbol 12,13-didecanoate, specifically stimulated the phosphorylation of two proteins in the erythrocyte membrane. They have apparent molecular weight of 100,000 dalton and 85,000 dalton. When intracellular calcium concentrations were raised by ionomycin, A23187, both the 85,000 dalton polypeptide and the 85K phosphoprotein were degraded. The 85,000 dalton phosphoprotein showed cross-reactivity with antiserum to human erythrocyte band 4.1. Based on its susceptibility to calcium-activated protease and its immunological property, the 85,000 dalton phosphoprotein was identified to be the band 4.1 of the erythrocyte membrane skeletal network.
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 callMore From: Biochemical and Biophysical Research Communications
Disclaimer: 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.
