title: PSMA7 directly interacts with NOD1 and regulates its function.
abstract: OBJECTIVE
  Recent reports showed that proteasome subunit alpha type-7 (PSMA7) was overexpressed in colorectal cancer. To investigate the mechanism of PSMA7 in promotion of colorectal cancer, we screened for its interaction partners.
  
  
  RESULTS
  This study found that PSMA7 associated with nucleotide-binding oligomerization domain-containing protein 1 (NOD1) by yeast two-hybrid screening, co-immunoprecipitation (IP), and GST-pull down assay. As shown by Western blotting and ubiquitin assay, PSMA7 downregulated the expression of NOD1 in a proteasome-dependent manner. Overexpression of PSMA7 in HCT116 cells resulted in an inhibition of NOD1-mediated apoptosis and NF-κB activation, whereas knockdown of PSMA7 by RNA interference enhanced NOD1 activity.
  
  
  CONCLUSIONS
  Our data suggest that PSMA7 is a negative regulator of the NOD1, and may promote tumor growth by its inhibitory role on NOD1.
authors.affiliation: Cancer Department of First Affiliated Hospital of Xinxiang Medical College Xinxiang, Henna, China.
authors.forename: Liuzhong
authors.initials: L
authors.lastname: Yang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Tang
authors.forename: Huiqiang
authors.initials: H
authors.lastname: Zhang
authors.forename: Weizheng
authors.initials: W
authors.lastname: Kou
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Lu
authors.forename: Xiaorui
authors.initials: X
authors.lastname: Li
authors.forename: Qiuping
authors.initials: Q
authors.lastname: Li
authors.forename: Zhanhui
authors.initials: Z
authors.lastname: Miao
mesh_terms: D017209:Apoptosis; D015536:Down-Regulation; D045325:HCT116 Cells; D057809:HEK293 Cells; D006801:Humans; D016328:NF-kappa B / Q000378:metabolism; D053474:Nod1 Signaling Adaptor Protein / Q000235:genetics / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D014162:Transfection; D020798:Two-Hybrid System Techniques; D054875:Ubiquitination
chemical_list: D016328:NF-kappa B; C119067:NOD1 protein, human; D053474:Nod1 Signaling Adaptor Protein; D034741:RNA, Small Interfering; C488662:PSMA7 protein, human; D046988:Proteasome Endopeptidase Complex