Characterization of Interaction Between Clathrin Light and Heavy Chains in <I>Arabidopsis</I>

Clathrin is a coat protein of a clathrin-coated vesicle (CCV), which sorts cargo proteins into various endosomes from trans-Golgi network and plasma membrane in mammalian, yeast and plant cells. The clathrin coat is composed of a microscopically visible structure with tree-legged shape, called triskelion. This triskelion comprises three clathrin heavy chains (CHCs), each harboring a single clathrin light chain (CLC). CHCs are well conserved among eukaryotic cells while CLCs vary in similarity, suggesting the latter may have an organism-specific function, but an interaction between CLC and CHC in Arabidopsis thaliana has not been analyzed in detail. In this study, the interaction of both types of Arabidopsis clathrin molecules was analyzed. Yeast two-hybrid and bimolecular fluorescence complementation analyses revealed Arabidopsis CLC actually interacted with CHC. Deletion analysis of CLC (1-258) showed an internal region of CLC (82-144) interacted with hub of CHC (1086-1705), suggesting the similar tendency of interaction of plant clathrin chains to that in mammalian cells. The analysis of the interaction of Arabidopsis CLC and CHC molecules will be discussed in this presentation,