Affiliation:
1. Department of Development and Signalling, AFRC Babraham Institute, Babraham, Cambridge CB2 4AT, U.K.
Abstract
PtdIns(4,5)P2 serves as a precursor of a diverse family of signalling molecules, including diacylglycerol (and hence phosphatidic acid), Ins(1,4,5)P3 [and hence Ins(1,3,4,5)P4] and PtdIns(3,4,5)P3. The production of these messengers can be activated by agonists, and therefore the rate of utilization of PtdIns(4,5)P2 can vary dramatically. Although cells can only meet these large changes in demand for PtdIns(4,5)P2 by increasing its synthesis and/or by continuously cycling it at a rate that exceeds its potential consumption (avoiding the need for a co-ordinated activation mechanism), no satisfactory explanation for how this is achieved in agonist-stimulated cells has yet been provided. We show here that, in streptolysin-O-permeabilized neutrophils, N-formylmethionyl-leucyl-phenylalanine (FMLP), platelet-activating factor (PAF) and non-hydrolysable GTP analogues can cause large activations of PtdIns4P 5-kinase, suggesting that cells can accommodate agonist-activated rates of consumption of PtdIns(4,5)P2 without having to sustain continuous, comparably rapid and energetically expensive ‘futile cycling’ reactions.
Subject
Cell Biology,Molecular Biology,Biochemistry
Cited by
60 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献