A novel hPirh2 splicing variant without ubiquitin protein ligase activity interacts with p53 and is down-regulated in hepatocellular carcinoma.
A novel splice variant of hPirh2, named hPirh2b, was isolated from human fetal liver cDNA library. hPirh2b has a 38-nucleotide deletion and encodes a 188-amino acid protein with a truncated RING-H2 domain. It shows no ubiquitin protein ligase activity. A low level of expression of hPirh2 was found both at transcriptional and translational level in human hepatocellular carcinoma (HCC) when compared to non-cancerous tissue. Statistical analysis showed that the low expression is associated with lack of differentiation of HCC. In direct binding studies hPirh2b bound p53 indicating that RING-H2 domain is not needed for this interaction.
Wu
Gang
G
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China.
Sun
Meiqian
M
Zhang
Liping
L
Zhou
Juan
J
Wang
Yi
Y
Huo
Keke
K
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D006528:Carcinoma, Hepatocellular / Q000378:metabolism*; D005982:Glutathione Transferase / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D047468:Immunoprecipitation; D008099:Liver / Q000378:metabolism; D008113:Liver Neoplasms / Q000378:metabolism*; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D010179:Pancreas / Q000378:metabolism; D011485:Protein Binding; D012326:RNA Splicing / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D016159:Tumor Suppressor Protein p53; C485369:RCHY1 protein, human; D044767:Ubiquitin-Protein Ligases; D005982:Glutathione Transferase