Acyl-CoA binding protein (ACBP) localizes to ER and Golgi in a ligand dependent manner in mammalian cells

Jesper S Hansen , Nils J Færgeman , Birthe B Kagelund , Jens Knudsen (1)

1 Department of Biochemistry and Molecular Biology

In the present study, we microinjected fluorescently labelled liver bovine ACBP (FACI-50), into HeLa and bovine mammary gland epithelial (BMGE) cell lines to characterize the localization and dynamics of ACBP in living cells. Results showed that ACBP targeted to the endoplasmic reticulum (ER) and Golgi in a ligand-binding dependent manner. A variant Y28F/K32A-FACI-50, which is unable to bind acyl-CoA, did no longer show association with ER and became segregated from Golgi, as analysed by intensity correlation calculations. Depletion of fatty acids from cells by addition of fatty acid free BSA (FAFBSA) significantly decreased FACI-50 association with Golgi, while fatty acid overloading increased Golgi-association, strongly supporting that ACBP associates with Golgi in a ligand-dependent manner. Fluorescence recovery after photobleaching (FRAP) showed that the fatty acid induced targeting of FACI-50 to Golgi resulted in a 5-fold reduction in FACI-50 mobility. We suggest that ACBP is targeted to ER and Golgi in a ligand-binding dependent manner in living cells, and propose that ACBP may be involved in vesicular trafficking.

Mots clés: Life Sciences

Jesper S Hansen, Nils J Færgeman, Birthe B Kagelund, Jens Knudsen. Acyl-CoA binding protein (ACBP) localizes to ER and Golgi in a ligand dependent manner in mammalian cells. Biochemical Journal, 2008, 410 (3), pp.463-472. ⟨10.1042/BJ20070559⟩. ⟨hal-00478794⟩