Motor proteins: intracellular transports and cellular morphogenesis

Cell Biology

Molecular motors are important for every possible regulated movement inside a cell. We focus on understanding the cellular functions of kinesin-2 and the role of Dynein Light Chain 1 (DLC1) in cell morphogenesis. Drosophila melanogaster is used as the model organism for these studies. The kinesin-2 subunits and DLC1 are genetically perturbed and their effects are studied on intracellular transport as well as on spermatogenesis by using a variety of different techniques. This helped establish two cellular models and a large collection of reagents and revealed two new properties. Kinesin-2 is found to independently transport choline acetyltransferase (ChAT) and acetyl cholinesterase (AChE) to the synapse, and a crucial Dynein independent role of DLC1 in the F-actin cone assembly during spermiogensis. At present we are studying the molecular basis of kinesin-2 assembly and DLC1 functions in vivo.

Publications

1. Doodhi H, Ghosal D, Krishnamurthy M, Jana SC, Divya S, Bhaduri A, Sowdhamini R, Ray K (2009) KAP, the Accessory Subunit of Kinesin-2 binds the Predicted Coiled-Coil Stalk of the Motor Subunits. Biochemistry 48: 2248
2. Ray K (2006) How Kinesins walk, assemble and transport: A bird's eye-view of some unresolved questions. Physica A 372: 52
3. Baqri R, Charan R, Shimmelfeng K, Chavan S, Ray K (2006) Kinesin-2 Differentially Regulates the Anterograde Axonal Transports of Acetylcholin-esterase and Choline Acetyltransferase in Drosophila. Journal of Neurobiology 66: 378
4. Ghosh-Roy A, Desai BS, Ray K (2005) Dynein Light Chain 1 Regulates Dynamin-mediated F-Actin Assembly during Sperm Individualization in Drosophila. Molecular Biology of Cell 16: 3107
5. Ghosh-Roy A, Kulkarni M, Kumar V, Shirolikar S, Ray K (2004) Cytoplasmic dynein-dynactin complex is required for spermatid growth but not axoneme assembly in Drosophila. Molecular Biology of Cell 15: 2470
6. Sarpal R, Todi SV, Sivan-Loukianova E, Shirolikar S, Subramanian N, Raff EC, Erickson JW, Ray K, Eberl DF (2003) Drosophila KAP interacts with the kinesin II motor subunit KLP64D to assemble chordotonal sensory cilia, but not sperm tails. Current Biology 13: 1687