HETERODIMERIZATION OF THE 2 MOTOR SUBUNITS OF THE HETEROTRIMERIC KINESIN, KRP(85 95)/

The heterotrimeric kinesin-related motor protein, KRP(85/95) is assemb led from two kinesin-related polypeptides, SpKRP85 and SpKRP95, togeth er with an uncharacterized 115 kDa polypeptide. Here we report the ded uced amino acid sequence of SpKRP95, a close relative of SpKRP85. Both SpKRP85 and SpKRP95 are predicted to have a tripartite domain organiz ation consisting of an N-terminal motor domain, a central stalk domain capable of coiled-coil formation, and a second globular C-terminal do main. The sequences of the central stalk domains predict that SpKRP85 and SpKRP95 should be capable of forming heterodimeric coiled coils. F urthermore, SpKRP85-SpKRP95 complexes can be immunoprecipitated from a cell-free translation system, providing direct evidence that SpKRP85 and SpKRP95 are capable of heterodimerization. (C) 1995 Academic Press Limited