Abstract
C. elegans have been used as a model organism for studying kinesins and dynein in neurons. In an effort to evaluate whether or not a C. elegans homolog of myosin-V exists, and therefore to gain a better understanding of axonal actin-based motors, a transcriptional fusion of hum-2 (supposedly an orthologue of mammalian myosin-V) has been created to detect its cellular expression. Moreover, initial worm behavioral and bioinformatics analysis have been performed to further characterize the role of this myosin (hum-2) in C. elegans. Online bioinformatics resources revealed similar predicted protein domains in the hum-2 gene when compared with mammalian myosin-V. Further, I performed behavioral analyses like chemotaxis, pumping rate and survival assays in a hum-2 mutant worm that displayed a defect in its chemosensory signaling as well as pumping rate. For the study of axonal transport, I carried out motility analyses and observed UNC-104 in hum-2 RNAi as well as mutant background. Results implicate significant changes in velocity, persistency of movement, total run length, pausing and motor reversals. Deeper kymograph analysis revealed a decrease in UNC-104 activation after a pause. Also, interestingly interaction between motile and non-motile UNC-104 clusters partially rescued UNC-104 activation. Finally, results revealed hum-2 expression in neurons, and its pivotal role in chemosensory signaling, pharynx pumping rate and also synaptic vesicle transport and UNC-104 activation.