Role of arabidopsis acyl-CoA-binding proteins in lipid trafficking (invited talk)

Abstract

Acyl-CoA-binding proteins (ACBPs) have been characterized from mammals, yeast, Drosophila and the model plants, Arabidopsis and rice. ACBPs contain a conserved acyl-CoA-binding domain which binds acyl-CoA esters and ACBPs can facilitate intracellular lipid transport. In Arabidopsis, a family of six genes encodes ACBPs which range from 10.4 kDa to 73.1 kDa. These ACBPs have been subcellularly localized to different compartments in the plant cell using autofluorescent-tagged proteins in confocal microscopy, immunoelectron microscopy and western blot analysis on subcellular fractions. Bacterial-expressed recombinant ACBPs have been generated and used for in vitro binding assays. Results from these assays indicate that these proteins exhibit differential binding affinities to acyl-CoA esters and phospholipids, implying that ACBPs have non-redundant biological functions in vivo. Investigations using knock-out acbp mutants and transgenic Arabidopsis lines that overexpress ACBPs demonstrate that Arabidopsis ACBPs can influence plant development and stress responses. Recent findings further suggest that the function of the various Arabidopsis ACBPs in binding lipids appears to be related to their biological functions in vivo.