title: Intracellular calcium levels can regulate Importin-dependent nuclear import.
abstract: We previously showed that increased intracellular calcium can modulate Importin (Imp)β1-dependent nuclear import of SRY-related chromatin remodeling proteins. Here we extend this work to show for the first time that high intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import generally. The basis of this relates to the mislocalisation of the transport factors Impβ1 and Ran, which show significantly higher nuclear localization in contrast to various other factors, and RCC1, which shows altered subnuclear localisation. The results here establish for the first time that intracellular calcium modulates conventional nuclear import through direct effects on the nuclear transport machinery.
authors: Nuclear Signalling Laboratory, Dept. of Biochemistry and Molecular Biology, Monash University, Australia.
authors: Gurpreet
authors: G
authors: Kaur
authors: Nuclear Signalling Laboratory, Dept. of Biochemistry and Molecular Biology, Monash University, Australia.
authors: Jennifer D
authors: JD
authors: Ly-Huynh
authors: Nuclear Signalling Laboratory, Dept. of Biochemistry and Molecular Biology, Monash University, Australia. Electronic address: David.Jans@monash.edu.
authors: David A
authors: DA
authors: Jans
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000502:physiology*; D000818:Animals; D019556:COS Cells; D002118:Calcium / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D002522:Chlorocebus aethiops; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism*; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D028961:beta Karyopherins / Q000378:metabolism*; D020931:ran GTP-Binding Protein / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D020662:Guanine Nucleotide Exchange Factors; C424166:KPNB1 protein, human; D009687:Nuclear Proteins; C062521:RCC1 protein, human; D028961:beta Karyopherins; D020931:ran GTP-Binding Protein; D002118:Calcium
keywords: Calcium; Importins; Nuclear import; Nucleocytoplasmic transport; Ran GTPase