RAB-GDP DISSOCIATION INHIBITOR ISOFORMS IN ARABIDOPSIS-THALIANA

Rab-GDP dissociation inhibitor protein (rab-GDI) plays an essential ro le in secretory pathways. To date, the question of multiplicity of GDI isoforms in higher plants remains open and dbEST search, PCR and Sout hern blot analysis have been used to assess the isoform composition of rab-GDI in Arabidopsis thaliana. A novel rab-GDI isoform, AtGD12, was identified which shares 90% identity in amino acid sequence with the known A. thaliana GDI and significantly differs from it by the structu re of its 5' and 3' untranslated regions.