Worm Breeder's Gazette 14(5): 70 (February 1, 1997)
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
Laboratory of Molecular Biology, Toyohashi University of Technology, Tempaku-cho, Toyohashi-441, JAPAN
Previously in Caenorhabditis elegans, three kinesin genes osm-3 IV, aka klp-2 (Shakir et al.,1993), unc-104 II, aka klp-1 (Otsuka et al., 1991), and unc-116, aka khc (Patel et al.,1993) have been characterized. unc-116 encoded kinesin heavy chain contains the motor, stalk, and tail domains (Patelet al.,1993). Mutants in unc-116 are defective in locomotion, smaller in size and have no backward locomotion. The unc-116 encoded khc is required at two discrete timesin development : once during very early embryogenesis,when it is supplied maternally, and the other during larval development, when the khc is transcribed from the zygotic genome ( David H.Hall, personal communication quoted by Patel et al., 1993). To study the temporal and spatial expression of unc-116, a unc-116::lacZ fusion gene was constructed. A 3.1 kb PstI-SalI fragment was obtained from the cosmid R05D3, encoding the unc-116 gene. The fragment contains 1.3 kb of the promoter and 1.7 kb of the coding region. This fragment was inserted in a lacZ expression vector pPD95.57, which included nuclear localization signal (Fire et al.,1996). Two independent transformed germ lines were obtained by microinjection, both of them showed an identical pattern of the lacZ staining. The staining of unc-116::lacZ reporter gene suggests that the unc-116 gene expresses during all larval and adult stages of C. elegans.Staining is also observed in the late embryos. It is found that the unc-116 gene expresses in a subset of cells in the two pharyngeal bulbs and in the tail. In L1 larva the staining is stronger in the posterior bulb than the anterior bulb. But in the adult animals the staining in both the anterior and posterior bulbs is stronger. Tentatively we have identified the staining cells in the posterior bulb as RMG, RIFL, RIS,ADA, ADE, AIM, AIY, AVA, AVB etc. and in the tail region PVT, PDB, PDA located in the pre-anal ganglion. Further confirmation of cell assignment is in progress using an unc-116::gfp construct. Interestingly, we have not seen staining of any ventral cord motor neurons, since the unc-116 mutants are defective in locomotion. This may suggest that the gene may express in the set of interneurons located in the head and tail, mediating locomotion. We are also examining the unc-116::lacZ gene expression in various genetic backgrounds to see the regulation of unc-116 gene expression in different mutant backgrounds. To observe the embryonic expression of the gene, we plan to use the in situ hybridization approach using a unc-116 cDNA probe ( yk41e9), in the wild type and mutant embryos. We thank A. Coulson, Y.Kohara, A.Fire, D.Thiery-Mieg, and T.Stiernagle for help in this project.