title: Vigilin interacts with CCCTC-binding factor (CTCF) and is involved in CTCF-dependent regulation of the imprinted genes Igf2 and H19.
abstract: CCCTC-binding factor (CTCF), a highly conserved zinc finger protein, is a master organizer of genome spatial organization and has multiple functions in gene regulation. Mounting evidence indicates that CTCF regulates the imprinted genes Igf2 and H19 by organizing chromatin at the Igf2/H19 locus, although the mechanism by which CTCF carries out this function is not fully understood. By yeast two-hybrid screening, we identified vigilin, a multi-KH-domain protein, as a new partner of CTCF. Subsequent coimmunoprecipitation and glutathione S-transferase pulldown experiments confirmed that vigilin interacts with CTCF. Moreover, vigilin is present at several known CTCF target sites, such as the promoter regions of c-myc and BRCA1, the locus control region of β-globin, and several regions within the Igf2/H19 locus. In vivo depletion of vigilin did not affect CTCF binding; however, knockdown of CTCF reduced vigilin binding to the H19 imprinting control region. Furthermore, ectopic expression of vigilin significantly downregulated Igf2 and upregulated H19, whereas depletion of vigilin upregulated Igf2 and downregulated H19, in HepG2, CNE1 and HeLa cells. These results reveal the functional relevance of vigilin and CTCF, and show that the CTCF-vigilin complex contributes to regulation of Igf2/H19.
authors.affiliation: Department of Biochemistry and Molecular Biology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, China.
authors.forename: Qiuying
authors.initials: Q
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Yang
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Xie
authors.forename: Ling
authors.initials: L
authors.lastname: Wei
authors.forename: Wenquan
authors.initials: W
authors.lastname: Liu
authors.forename: Wenli
authors.initials: W
authors.lastname: Yang
authors.forename: Yajun
authors.initials: Y
authors.lastname: Ge
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhu
authors.forename: Junzhe
authors.initials: J
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Jiang
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Yu
authors.forename: Wenyan
authors.initials: W
authors.lastname: Shen
authors.forename: Ran
authors.initials: R
authors.lastname: Li
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Shi
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.forename: Yang
authors.initials: Y
authors.lastname: Qin
mesh_terms: D001483:Base Sequence; D000076246:CCCTC-Binding Factor; D045744:Cell Line, Tumor; D017931:DNA Primers; D005786:Gene Expression Regulation; D018392:Genomic Imprinting; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D011485:Protein Binding; D034622:RNA Interference; D062085:RNA, Long Noncoding / Q000235:genetics*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020798:Two-Hybrid System Techniques
chemical_list: D000076246:CCCTC-Binding Factor; C000619697:CTCF protein, human; D017931:DNA Primers; C094335:H19 long non-coding RNA; D062085:RNA, Long Noncoding; D016601:RNA-Binding Proteins; D012097:Repressor Proteins; C075197:high density lipoprotein binding protein; D007335:Insulin-Like Growth Factor II
keywords: CCCTC-binding factor; H19; Igf2; Vigilin; gene regulation