title: Short Hypocotyl in White Light1 Interacts with Elongated Hypocotyl5 (HY5) and Constitutive Photomorphogenic1 (COP1) and Promotes COP1-Mediated Degradation of HY5 during Arabidopsis Seedling Development.
abstract: Arabidopsis (Arabidopsis thaliana) Short Hypocotyl in White Light1 (SHW1) encodes a Ser-Arg-Asp-rich protein that acts as a negative regulator of photomorphogenesis. SHW1 and Constitutive Photomorphogenic1 (COP1) genetically interact in an additive manner to suppress photomorphogenesis. Elongated Hypocotyl5 (HY5) is a photomorphogenesis promoting a basic leucine zipper transcription factor that is degraded by COP1 ubiquitin ligase in the darkness. Here, we report the functional interrelation of SHW1 with COP1 and HY5 in Arabidopsis seedling development. The in vitro and in vivo molecular interaction studies show that SHW1 physically interacts with both COP1 and HY5. The genetic studies reveal that SHW1 and HY5 work in an antagonistic manner to regulate photomorphogenic growth. Additional mutation of SHW1 in hy5 mutant background is able to suppress the gravitropic root growth defect of hy5 mutants. This study further reveals that the altered abscisic acid responsiveness of hy5 mutants is modulated by additional loss of SHW1 function. Furthermore, this study shows that SHW1 promotes COP1-mediated degradation of HY5 through enhanced ubiquitylation in the darkness. Collectively, this study highlights a mechanistic view on coordinated regulation of SHW1, COP1, and HY5 in Arabidopsis seedling development.
authors.affiliation: Department of Biotechnology, National Institute of Technology, Durgapur 713209, India.
authors.forename: Anjil Kumar
authors.initials: AK
authors.lastname: Srivastava
authors.affiliation: Department of Biotechnology, National Institute of Technology, Durgapur 713209, India.
authors.forename: Dhirodatta
authors.initials: D
authors.lastname: Senapati
authors.affiliation: Department of Biotechnology, National Institute of Technology, Durgapur 713209, India.
authors.forename: Archana
authors.initials: A
authors.lastname: Srivastava
authors.affiliation: Department of Biotechnology, National Institute of Technology, Durgapur 713209, India.
authors.forename: Moumita
authors.identifier: http://orcid.org/0000-0002-6093-0889
authors.initials: M
authors.lastname: Chakraborty
authors.affiliation: Department of Biotechnology, National Institute of Technology, Durgapur 713209, India.
authors.forename: Sreeramaiah N
authors.identifier: http://orcid.org/0000-0003-1087-1523
authors.initials: SN
authors.lastname: Gangappa
authors.affiliation: Department of Biotechnology, National Institute of Technology, Durgapur 713209, India sudipchatto@gmail.com.
authors.forename: Sudip
authors.identifier: http://orcid.org/0000-0001-5253-6673
authors.initials: S
authors.lastname: Chattopadhyay
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000528:radiation effects; D008027:Light; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D063246:Organogenesis, Plant / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D010937:Plant Growth Regulators / Q000494:pharmacology; D011485:Protein Binding; D059748:Proteolysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases; D054875:Ubiquitination / Q000187:drug effects / Q000528:radiation effects
chemical_list: D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; C109254:HY5 protein, Arabidopsis; D009687:Nuclear Proteins; D010937:Plant Growth Regulators; C530965:SHW1 protein, Arabidopsis; D000040:Abscisic Acid; C471983:AT2G32950 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases