title: Protein solubility and folding enhancement by interaction with RNA.
abstract: While basic mechanisms of several major molecular chaperones are well understood, this machinery has been known to be involved in folding of only limited number of proteins inside the cells. Here, we report a chaperone type of protein folding facilitated by interaction with RNA. When an RNA-binding module is placed at the N-terminus of aggregation-prone target proteins, this module, upon binding with RNA, further promotes the solubility of passenger proteins, potentially leading to enhancement of proper protein folding. Studies on in vitro refolding in the presence of RNA, coexpression of RNA molecules in vivo and the mutants with impaired RNA binding ability suggests that RNA can exert chaperoning effect on their bound proteins. The results suggest that RNA binding could affect the overall kinetic network of protein folding pathway in favor of productive folding over off-pathway aggregation. In addition, the RNA binding-mediated solubility enhancement is extremely robust for increasing soluble yield of passenger proteins and could be usefully implemented for high-throughput protein expression for functional and structural genomic research initiatives. The RNA-mediated chaperone type presented here would give new insights into de novo folding in vivo.
authors.affiliation: Institute of Life Science and Biotechnology, Yonsei University, Seodaemun-Gu, Seoul, Korea.
authors.forename: Seong Il
authors.initials: SI
authors.lastname: Choi
authors.forename: Kyoung Sim
authors.initials: KS
authors.lastname: Han
authors.forename: Chul Woo
authors.initials: CW
authors.lastname: Kim
authors.forename: Ki-Sun
authors.initials: KS
authors.lastname: Ryu
authors.forename: Byung Hee
authors.initials: BH
authors.lastname: Kim
authors.forename: Kyun-Hwan
authors.initials: KH
authors.lastname: Kim
authors.forename: Seo-Il
authors.initials: SI
authors.lastname: Kim
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Kang
authors.forename: Hang-Cheol
authors.initials: HC
authors.lastname: Shin
authors.forename: Keo-Heun
authors.initials: KH
authors.lastname: Lim
authors.forename: Hyo Kyung
authors.initials: HK
authors.lastname: Kim
authors.forename: Jeong-Min
authors.initials: JM
authors.lastname: Hyun
authors.forename: Baik L
authors.initials: BL
authors.lastname: Seong
mesh_terms: D003600:Cytosol / Q000378:metabolism; D004247:DNA / Q000737:chemistry; D004742:Enhancer Elements, Genetic; D006801:Humans; D008957:Models, Genetic; D018832:Molecular Chaperones / Q000737:chemistry; D016297:Mutagenesis, Site-Directed; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D011489:Protein Denaturation; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry*; D012313:RNA / Q000737:chemistry*; D012995:Solubility
chemical_list: D018832:Molecular Chaperones; D011506:Proteins; D012313:RNA; D004247:DNA