Cloning and functional characterization of GMPR2, a novel human guanosine monophosphate reductase, which promotes the monocytic differentiation of HL-60 leukemia cells.
OBJECTIVE
To identify the biological function of a novel molecule which shows high homology with human guanosine monophosphate reductase (GMPR) and is named GMPR2.


METHODS
GMPR2 cDNA was cloned from the cDNA library of human dendritic cells and was characterized by Bioinformatics. The expression pattern of GMPR2 was analyzed by Northern blotting. The enzymatic activity of the purified recombinant GMPR2 protein was determined using a spectrophotometric assay. HL-60 leukemia cells were transfected with GMPR2 and the expression of CD14 and myeloperoxidase (MPO) in HL-60 cells with and without 12- o-tetra-decanoyl-phorbol-13-acetate (TPA) induction was monitored by FACS analysis.


RESULTS
The novel gene contained ten exons and nine introns and was mapped to 14q11-21. Northern blotting indicated a ubiquitous expression of GMPR2 mRNA in most of the human tissues and cancer cell lines investigated. The recombinant GMPR2 protein was able to reduce GMP. The expression of CD14 and MPO in HL-60 leukemia cells overexpressing GMPR2 clearly increased after induction by TPA.


CONCLUSIONS
GMPR2 is a novel human GMP reductase, and overexpression of GMPR2 can promote the monocytic differentiation of HL-60 leukemia cells.
Zhang
Jia
J
Institute of Immunology and Department of Internal Medicine, Second Military Medical University, 800 Xiangyin Road, 200433, Shanghai, P.R. China.
Zhang
Weiping
W
Zou
Dajin
D
Chen
Guoyou
G
Wan
Tao
T
Zhang
Minghui
M
Cao
Xuetao
X
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D002454:Cell Differentiation; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis; D050899:GMP Reductase; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D018922:HL-60 Cells; D006801:Humans; D008969:Molecular Sequence Data; D009000:Monocytes / Q000201:enzymology* / Q000473:pathology; D009247:NADH, NADPH Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
D018076:DNA, Complementary; D009247:NADH, NADPH Oxidoreductases; D050899:GMP Reductase