title: Functional interplay between the RK motif and linker segment dictates Oct4-DNA recognition.
abstract: The POU family transcription factor Oct4 plays pivotal roles in regulating pluripotency and somatic cell reprogramming. Previous studies have indicated an important role for major groove contacts in Oct4-DNA recognition; however, the contributions of the RK motif in the POUh domain and the linker segment joining the two DNA-binding domains remain poorly understood. Here, by combining molecular modelling and functional assays, we find that the RK motif is essential for Oct4-DNA association by recognizing the narrowed DNA minor groove. Intriguingly, computational simulations reveal that the function of the RK motif may be finely tuned by H-bond interactions with the partially disordered linker segment and that breaking these interactions significantly enhances the DNA binding and reprogramming activities of Oct4. These findings uncover a self-regulatory mechanism for specific Oct4-DNA recognition and provide insights into the functional crosstalk at the molecular level that may illuminate mechanistic studies of the Oct protein family and possibly transcription factors in the POU family. Our gain-of-function Oct4 mutants might also be useful tools for use in reprogramming and regenerative medicine.
authors: Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Xiangqian
authors: X
authors: Kong
authors: Chinese Academy of Sciences Key Laboratory of Receptor Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Jian
authors: J
authors: Liu
authors: Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Lianchun
authors: L
authors: Li
authors: Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Liyan
authors: L
authors: Yue
authors: Chinese Academy of Sciences Key Laboratory of Receptor Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Lihong
authors: L
authors: Zhang
authors: Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
authors: Hualiang
authors: H
authors: Jiang
authors: Chinese Academy of Sciences Key Laboratory of Receptor Research, National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China xxie@simm.ac.cn.
authors: Xin
authors: X
authors: Xie
authors: Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China cluo@simm.ac.cn.
authors: Cheng
authors: C
authors: Luo
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D001665:Binding Sites; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D051379:Mice; D056004:Molecular Dynamics Simulation; D009154:Mutation; D009690:Nucleic Acid Conformation; D050814:Octamer Transcription Factor-3 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D055672:Static Electricity; D015533:Transcriptional Activation
chemical_list: D050814:Octamer Transcription Factor-3; D004247:DNA