title: CCCTC-binding factor controls its own nuclear transport via regulating the expression of importin 13.
abstract: CCCTC-binding factor (CTCF), a multivalent zinc-finger protein, is involved in different aspects of regulation including promoter activation or repression, gene silencing, chromatin insulation, gene imprinting, X-chromosome inactivation, cell growth or differentiation and tumor genesis. However, the molecular mechanisms of CTCF nuclear import remains unclear. In this study, we showed that the expression of CTCF influenced the intracellular distribution of itself, which might go through transport receptor - import 13 (IPO13). We further confirmed that there is a CTCF target site in ipo13 -774∼-573 bp promoter region and CTCF regulates the expression of IPO13. Besides, GST pull-down and Co-IP experiments demonstrated that CTCF interacts with IPO13. Immunofluorescence staining showed that IPO13 influenced intracellular distribution of CTCF. In all, we conclude that CTCF regulates the expression of IPO13, which, in turn, mediates the nuclear import of CTCF.
authors.affiliation: Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Wang
authors.forename: Jingjing
authors.initials: J
authors.lastname: Shen
authors.forename: Peitang
authors.initials: P
authors.lastname: Huang
authors.forename: Xudong
authors.initials: X
authors.lastname: Zhu
mesh_terms: D021581:Active Transport, Cell Nucleus; D000076246:CCCTC-Binding Factor; D045744:Cell Line, Tumor; D002843:Chromatin / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D020868:Gene Silencing; D006801:Humans; D028884:Karyopherins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism*
chemical_list: D000076246:CCCTC-Binding Factor; C000619697:CTCF protein, human; D002843:Chromatin; C527880:IPO13 protein, human; D028884:Karyopherins; D012097:Repressor Proteins