title: Identification of the binding domains and key amino acids for the interaction of the transcription factors BmPOUM2 and BmAbd-A in Bombyx mori.
abstract: The transcription factor BmPOUM2 interacted with another transcription factor BmAbd-A to regulate the expression of the wing cuticle protein gene BmWCP4 in Bombyx mori. In this study, the binding domains and amino acids for the interaction between BmPOUM2 and BmAbd-A were reported. Two isoforms of BmPOUM2 were identified. The short isoform (BmPOUM2-S) lacks a 114-amino acid sequence containing a POU-homeodomain and a nuclear localization signal peptide (NLS), as compared to the full-length isoform (BmPOUM2). Both BmPOUM2 and BmPOUM2-S proteins bound to the BmAbd-A through the POU-specific domain. When the six amino acids (Lys166, Gly173, Gln176, Ser192, Glu200 and Asn208) that are highly conserved in POU family genes were mutated, BmPOUM2 did not bind to BmAbd-A. BmAbd-A interacted with BmPOUM2 by the homeobox domain or the LCR2 (low complexity region) domain. When seven amino acids (Phe156/248, His158/250, Ala175/263, Cys180/265, Glu190/268, Trp196/274 and Val214/289) that are shared in the homeobox and LCR2 domains were mutated, BmAbd-A did not bind to BmPOUM2. Overexpression of either BmPOUM2 or BmAbd-A or both increased the activity of BmWCP4 promoter in CHO cells. ChIP assay and EMSA showed that BmAbd-A protein bound to the Hox cis-regulatory element in the BmWCP4 promoter, while the BmPOUM2 bound to the nearby POU CRE. A model for the interaction and action of BmPOUM2 and BmAbd-A in regulation of the BmWCP4 expression is proposed.
authors.affiliation: Guangzhou Key Laboratory of Insect Development Regulation and Application Research, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: He
authors.affiliation: Guangzhou Key Laboratory of Insect Development Regulation and Application Research, School of Life Sciences, South China Normal University, Guangzhou, 510631, China. Electronic address: denghuiminmin@163.com.
authors.forename: Huimin
authors.initials: H
authors.lastname: Deng
authors.affiliation: Guangzhou Key Laboratory of Insect Development Regulation and Application Research, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
authors.forename: Qihao
authors.initials: Q
authors.lastname: Hu
authors.affiliation: Guangzhou Key Laboratory of Insect Development Regulation and Application Research, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
authors.forename: Zidan
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Guangzhou Key Laboratory of Insect Development Regulation and Application Research, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Liu
authors.affiliation: Guangzhou Key Laboratory of Insect Development Regulation and Application Research, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
authors.forename: Sichun
authors.initials: S
authors.lastname: Zheng
authors.affiliation: Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Qisheng
authors.initials: Q
authors.lastname: Song
authors.affiliation: Guangzhou Key Laboratory of Insect Development Regulation and Application Research, School of Life Sciences, South China Normal University, Guangzhou, 510631, China. Electronic address: qlfeng@scnu.edu.cn.
authors.forename: Qili
authors.initials: Q
authors.lastname: Feng
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000378:metabolism*; D016466:CHO Cells; D003412:Cricetulus; D018398:Homeodomain Proteins / Q000378:metabolism*; D019476:Insect Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: C410542:Abd-A protein, insect; D018398:Homeodomain Proteins; D019476:Insect Proteins; D020033:Protein Isoforms; D014157:Transcription Factors
keywords: Binding domain; BmAbd-A; BmPOUM2; Bombyx mori; Protein interaction; Transcription factor