The nuclear localization signal of mitotic kinesin-like protein Mklp-1: effect on Mklp-1 function during cytokinesis.
The mitotic kinesin-like protein (Mklp-1) localizes in the nucleus during interphase due to the presence of nuclear localization signal(s) [NLS(s)] within its sequence. Here, we mapped two NLSs to be 899SRKRRSST906 and 949KRKKP953 in the tail domain of Mklp-1, and showed that ectopic expression of a mutant Mklp-1 without the NLSs leads to cell cycle arrest at cytokinesis, indicating that the NLSs are necessary for Mklp-1 to execute its normal function during cell division. Furthermore, mutation of two serine residues in the first NLS to aspartic acid, which mimics phosphorylation, attenuated its nuclear localization function, suggesting that the function of this NLS might be regulated by phosphorylation.
Liu
Xiaoqi
X
Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA. liu8@purdue.edu
Erikson
Raymond L
RL
D000595:Amino Acid Sequence; D015153:Blotting, Western; D002453:Cell Cycle / Q000235:genetics / Q000502:physiology; D018797:Cell Cycle Proteins / Q000378:metabolism; D048749:Cytokinesis / Q000235:genetics / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009154:Mutation; D019913:Nuclear Localization Signals / Q000235:genetics*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D000097869:Polo-Like Kinase 1
D018797:Cell Cycle Proteins; D049452:Green Fluorescent Proteins; D008869:Microtubule-Associated Proteins; D019913:Nuclear Localization Signals; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D011993:Recombinant Fusion Proteins; D000097869:Polo-Like Kinase 1; C092935:KIF23 protein, human