Kinesin is a microtuble based molecular motor that moves cellular cargo on microtubule tracks. C.elegans kinesin heavy chain contains all three domains: an amino- terminal globular motor domain, a central rod domain that allow dimer formation and a C-terminal tail domain that binds light chains and carries cellular cargo (Patel et al.,1993).Here we report temporal and spatial expression of the UNC-116 coded kinesin heavy chain (KHC) for two different promoter constructs, and the genetic interaction between mutants in
unc-116 and
unc-104,
vab-8 and
osm-3, encoding other kinesin like proteins. As previously reported, the smaller promoter fusion gene of
unc-116-S::lacZ expresses in a set of interneurons and motor neurons in the anterior ganglia located in the head,and in the pre-anal ganglion.(WBG 14, #5,
p70, 1997, and C. elegans meeting 1997).This reporter gene staining is seen in all developmental stages of animals including embryos; however, no staining is seen in the ventral cord motor neurons which was expected since
unc-116 is defective in locomotion. We therefore constructed a larger
unc-116-L::lacZ promoter that added 341 upstream sequence in the promoter region, and fused it with the same pPD95.57 (A.Fire, 1995) lacZ expresion vector. Four germline transgenics were obtained by injecting this large promoter construct and all of them showed an identical pattern of lacZ staining. Intense staining was observed in late embryos, all larval stages and in adults of both sexes.In particular, the body wall and pharyngeal muscles,stained weakly in young larvae, but staining increases gradually, reaching a maximum in L3-L4 stage and stays that way during the adult stage. Staining in the nervous system is widespread and strong, including the set of motor neurons along the ventral nerve cord, nerve ring in the head, neurons in the anterior and posterior ganglia.In the pharynx, cells in the anterior and terminal bulb are strongly stained. Staining of sensory neurons in the head (amphid and labial) and in the tail (phasmid) is weak but noticeable.The ventral and dorsal nerve cords and some lateral processes are also stained. We have observed the expression of
unc-116-L::lacZ reporter gene in different mutant backgrounds, and find that the expression in the muscle and motor neurons is significantly reduced specially in larval stages in the
unc-104(rh 1016) mutant background. Similarly expression of the reporter gene is extremely reduced or abnormal in the muscle cells in the
vab-8(
e1017) mutant background. Abnormal staining is found in the posterior of the animal in
vab-8 mutant background. Whereas, there is no significant change of the staining in the
osm-3 mutant background. The double mutants
unc-116(
rh24);
vab-8(
e1017) is lethal. On the other hand,
unc-116(
e2310);
osm-3(
p802) is a usual double,uncoordinated and osmotic defective which is consistent with the mutant background expression results. Since UNC-104 and VAB-8 are kinesin like proteins, these observations suggest interaction of multiple kinesins in muscle and neural development of C.elegans. We thank D. Thierry-Mieg, E. Hedgecock, A. Otsuka,, D. Hall, R. Holmgren, J. Miwa,and J. white for encouragement; Theresa Stierngale and A.Fire for strains and vectors, and Sanger Centre for genomic sequence information.