Lipid dynamics in the annexin V - membrane complex

The influence of annexin V on the lateral diffusion of phosphatidylcholine (PC) and phosphatidylserine (PS) were previously investigated by Fluorescen ce Recovery After Photobleaching (FRAP), while its effects on acyl chain mo tions were studied by H-2 NMR spectroscopy and fluorescence polarisation (S aurel et al., 1998, Biochemistry, 37, 1403-1410; Cezanne et al.,1999 Bioche mistry, 38, 2779-2786). In the present paper, the lipid polar head's orient ations were analysed, by 2H NMR spectroscopy on oriented bilayers labelled with DMPC-alpha beta-d(4) and POPS-alpha beta-d(3). All the results were an alysed, taking into account the time constant of each method, and a detaile d description of the lipid dynamics in this proteolipidic complex is propos ed.