Oil bodies and their associated proteins, oleosin and caleosin

Oil bodies are lipid storage organelles which have been analyzed biochemica lly due to the economic importance of oil seeds, Although oil bodies are st ructurally simple, the mechanisms involved in their formation and degradati on remain controversial. At present, only two proteins associated,vith oil bodies have been described, oleosin and caleosin. Oleosin is thought to be important for oil body stabilization in the cytosol, although neither the s tructure nor the function of oleosin has been fully elucidated. Even less i s known about caleosin, which has only recently been described [Chen et al, (1999) Plant Cell Physiol 40: 1079-1086; N ae sted et al. (2000) Plant Mol Biol 44: 463-476], Caleosin and caleosin-like proteins are not unique to o il bodies and are associated with an endoplasmatic reticulum subdomain in s ome cell types. Here me review the synthesis and degradation of oil bodies as they relate to structural and functional aspects of oleosin and caleosin .