Study of reversal behavior and chemotaxis in Caenorhabditis elegans

Abstract

The free living nematode C. elegans is an important yet simple animal to study various newlinebehaviours and their underlying neuronal circuits. Having just 302 neurons and a transparent newlinebody allows researchers to study and trace new molecules and pathways in the nervous system newlineIn First half, I will talk about how the level of AMPA type glutamate receptor (GLR-1) on newlineneuronal cells is regulated through the endocytic pathways. In case of endocytic pathways newlinedifferent organelles are involved in trafficking; one such organelle is the endocytic recycling newlinecompartment (ERC) which plays important role in recycling of trafficked cargos. AMPA/GLR-1 newlinereceptors are also maintained through the ERC pathways, any defect in the pathway leads to newlinedecrease in the active receptors on the membrane. In case of C. elegans, decrease in active newlineamounts of AMPA/GLR-1 receptors on neuronal membranes results in behavioural newlineconsequences such as altered reversals. Further, the mechanism of such molecules that are newlineinvolved in recycling of these cargos in the ERC will be discussed. newlineIn second part, I will talk about newly identified G-protein Coupled receptor (GPCR) and its role newlinein chemosensory neurons of C. elegans. Chemosensation is the only way to navigate the newlinesurrounding for a blind animal like C. elegans. Through chemosensation C. elegans searches for newlinefood, mates and successfully escapes danger. Majority of the chemosensory neurons are present newlinein the head and a few are found in the tail. These chemosensory neurons express numerous newlineGPCRs which act as receptors for the surrounding cues and activate downstream signalling newlinepathways that help the animal to modulate behaviours. Some GPCR enable C. elegans to sense newlinelower and higher concentrations of chemicals. We have found an as yet undescribed GPCR newlinewhich specifically senses higher concentrations of chemical and the loss of which results in newlineaberrant animal behaviour. newline