Abstract
Myosin IC (MyoIC) is a member of the myosin superfamily that plays an important role in dynamic nuclear processes such as transcription and chromosome translocation. But how the nuclear functions of MyoIC are regulated, including how myosin IC gets into and out of the nucleus is not known. Understanding the mechanisms that contribute to the nucleo-cytoplasmic transport of MyoIC will provide valuable insights into its nuclear function regulation. The objective of this study was to identify the nuclear export signal (NES) of MyoIC. To this effect, I created various MyoIC-GFP expression constructs with deletions or mutations in specific amino acids using site directed mutagenesis. These constructs were expressed in mammalian cells and the cellular localization of the GFP-fusion proteins was analyzed through GFP fluorescence by microscopic imaging. In addition, cells expressing various constructs were treated with Leptomycin B, a known pharmacological NES inhibitor and analyzed for changes in the cellular localization of the respective constructs. Results from these experiments suggest the presence of an NES in tail region of MyoIC. These data are an important first step in identifying the pathways and factors that contribute to the nuclear localization of MyoIC.
