Identification of a novel isoform of DHRS4 protein with a nuclear localization signal.
The DHRS4 gene encodes an NADP(H)-dependent retinol dehydrogenase/reductase (NRDR) and plays an important role in regulating the synthesis of retinoic acid. In the present study, we identified a novel splice RNA variant, designated NRDRA2, of the human DHRS4 gene by RT-PCR, 3' RACE, and 5' RACE. NRDRA2 mRNA lacked exons 4 and 6, and had a shift in the reading frame when compared to DHRS4 mRNA, resulting in loss of the peroxisomal targeting signal of NRDR and gain of a nuclear localization signal in the predicted NRDRA2 protein. Endogenous NRDRA2 protein was identified in the human cervical carcinoma cell line HeLa by immunoprecipitation and mass spectrometric assay. A green fluorescent protein reporter assay showed that NRDRA2 protein mainly localized to the nuclei, confirming the sequence at its C-terminus as a legitimate nuclear localization signal sequence. This study identifies the alternative transcript variant NRDRA2 encoding a subcellular nuclear localized NRDRA2 protein.
Department of Cell Biology, Shantou University Medical College, Shantou Guangdong, China.
Zhongjing
Z
Su
Rui
R
Li
Xuhong
X
Song
Gefei
G
Liu
Yifan
Y
Li
Xiaolan
X
Chang
Congzhu
C
Li
Dongyang
D
Huang
D000595:Amino Acid Sequence; D001483:Base Sequence; D002460:Cell Line; D006367:HeLa Cells; D006801:Humans; D019913:Nuclear Localization Signals / Q000235:genetics; D010088:Oxidoreductases / Q000235:genetics* / Q000302:isolation & purification*; D020033:Protein Isoforms / Q000096:biosynthesis* / Q000235:genetics; D014162:Transfection
D019913:Nuclear Localization Signals; D020033:Protein Isoforms; D010088:Oxidoreductases; C539685:DHRS4 protein, human