title: HC-Pro protein of Potato virus Y can interact with three Arabidopsis 20S proteasome subunits in planta.
abstract: The multifunctional protein helper component proteinase (HC-Pro) is thought to interfere with the activity of the 20S proteasome; however, no sites of interaction have been identified for either protein. Here, we first show that the Potato virus Y (PVY) HC-Pro protein can interact with three Arabidopsis 20S proteasome subunits (PAA, PBB, and PBE), using a yeast two-hybrid system and the bimolecular fluorescence complement assay. In addition, yeast two-hybrid analysis of the interaction between several mutant subunits of the 20S proteasome and PVY HC-Pro confirmed that residues 81 to 140 of PAA, 1 to 80 of PBB, and 160 to 274 of PBE are necessary for binding PAA, PBB, and PBE to PVY HC-Pro, respectively. Deletion mutant analysis of PVY HC-Pro showed that the N terminus (residues 1 to 97) is necessary for its interaction with three Arabidopsis 20S proteasome subunits. The ability of HC-Pro to interact and interfere with the activity of the 20S proteasome may help explain the molecular basis of its multifunctional character.
authors: State Key Laboratory of Agro-biotechnology, China Agricultural University, 2 Yuanmingyuan West Road, Haidian District, Beijing 100094, PR China.
authors: Yongsheng
authors: Y
authors: Jin
authors: Dongyuan
authors: D
authors: Ma
authors: Jiangli
authors: J
authors: Dong
authors: Jingchen
authors: J
authors: Jin
authors: Daofeng
authors: D
authors: Li
authors: Changwang
authors: C
authors: Deng
authors: Tao
authors: T
authors: Wang
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics; D017360:Arabidopsis / Q000821:virology*; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D020125:Mutation, Missense; D010940:Plant Proteins / Q000378:metabolism*; D017800:Potyvirus / Q000502:physiology*; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D025941:Protein Interaction Mapping; D017384:Sequence Deletion; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D014764:Viral Proteins; D003546:Cysteine Endopeptidases; C072775:HC-Pro protein, potyvirus; D046988:Proteasome Endopeptidase Complex