A Comparison of the Membrane Binding Properties of C1B Domains of PKC gamma, PKC delta, and PKC epsilon

作者：Sanchez Bautista Sonia; Corbalan Garcia Senena; Perez Lara Angel; Gomez Fernandez Juan C^*

来源：Biophysical Journal, 2009, 96(9): 3638-3647.

DOI：10.1016/j.bpj.2009.02.021

The C1 domains of classical and novel PKCs mediate their diacylglycerol-dependent translocation. Using fluorescence resonance energy transfer, we studied the contribution of different negatively charged phospholipids and diacylglycerols to membrane binding. Three different C1B domains of PKCs were studied (the classical gamma, and the novel delta and epsilon), together with different lipid mixtures containing three types of acidic phospholipids and three types of activating diacylglycerols. The results show that C1 By and C1 BE exhibit a higher affinity to bind to vesicles containing 1-palmitoyl-2-oleoyl-sn-phosphatidic acid, 1-palmitoyl-2-oleoyl-sn-phoshatidylserine, or 1-palmitoyl-2-oleoyl-sn-phosphatidylglycerol, with C1B epsilon being the most relevant case because its affinity for POPA-containing vesicles increased by almost two orders of magnitude. When the effect of the diacylglycerol fatty acid composition on membrane binding was studied, the C1B epsilon domain showed the highest binding affinity to membranes containing 1-stearoyl-oleoyl-sn-glycerol or 1,2-sn-dioleoylglycerol with POPA as the acidic phospholipid. Of the three diacylglycerols used in this study, 1,2-sn-dioleoylglycerol and 1-stearoyl-oleoyl-sn-glycerol showed the highest affinities for each isoenzyme, whereas 1,2-sn-dipalmitoylglycerol; showed the lowest aff inity. DSC experiments showed this to be a consequence of the nonfluid conditions of 1,2-sn-dipalmitoylglycerol;-containing systems.

• 出版日期2009-5-6