Two bipartite NLSs mediate constitutive nuclear localization of Mcm10.
Some components of the pre-replicative complex (pre-RC) are in the nucleus only during the G1 phase, while others are constitutively nuclear throughout the cell cycle. A nuclear localization signal (NLS) mediating the G1-specific nuclear localization has been characterized. We report here the identification of bipartite NLSs in constitutively nuclear pre-RC components, including the origin recognition complex, Mcm10 and Noc3. Interestingly, in a subgroup of these pre-RC components, two putative NLSs were found in each protein. To examine whether multiple NLSs are required for these proteins to be nuclear throughout the cell cycle, we characterized the two NLSs in Mcm10. We show that at least one of the two NLSs is required for directing Mcm10 into the nucleus and that either of them is sufficient to bring the green fluorescence protein into the nucleus. Thus, Mcm10 contains two functional NLSs and either is sufficient for the constitutive nuclear localization of Mcm10.
D015153:Blotting, Western; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism / Q000502:physiology*; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D016193:G1 Phase / Q000502:physiology*; D049452:Green Fluorescent Proteins; D007211:Indoles; D008164:Luminescent Proteins / Q000378:metabolism; D008856:Microscopy, Fluorescence; D064110:Minichromosome Maintenance Proteins; D019913:Nuclear Localization Signals / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D029543:Nucleocytoplasmic Transport Proteins; D051738:Origin Recognition Complex; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism
D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D007211:Indoles; D008164:Luminescent Proteins; C076365:MCM10 protein, S cerevisiae; C429648:NOC3 protein, S cerevisiae; D019913:Nuclear Localization Signals; D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; D051738:Origin Recognition Complex; D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins; C007293:DAPI; D064110:Minichromosome Maintenance Proteins