Molecular cloning, characterization and isolation of novel spliced variants of the human ortholog of a rat estrogen-regulated membrane-associated protein, UO-44.
We have previously reported the characterization of an estrogen-regulated rat uterine-ovarian-specific complementary DNA (UO-44). To understand the involvement of this protein in the initiation and progression of human ovarian and uterine cancers, we now report the cloning and characterization of the human ortholog (HuUO-44). HuUO-44 is mapped to chromosome 10q26.13 and contains nine exons. Multiple tissue Northern blot detected two HuUO-44 transcripts of approximately 2 and 3 kb in the pancreas. RT-PCR demonstrated that HuUO-44 undergoes a complex series of alternative splicing events between exons 2 and 6 that yielded four novel splice variants, HuUO-44A, HuUO-44B, HuUO-44C and HuUO-44D. Putative functional motifs identified in HuUO-44 are two CUB domains and a zona-pellucida domain. Transfection studies demonstrated the membrane-associated nature of HuUO-44. By immunohistochemistry, HuUO-44 was located to the normal ovarian and ovarian tumor epithelial cells; in NIH-OVCAR3 ovarian cancer cells, HuUO-44 was detected only at the leading edge of the dividing cells. Most importantly, a marked loss in cell attachment and proliferation was observed in NIH-OVCAR3 cells cultured in the presence of a polyclonal HuUO-44 antiserum. These findings suggest the potential role of HuUO-44 in cell motility, cell-cell interactions and/or interactions with the extracellular matrices.
Leong
Caine Tuck Choy
CT
Laboratory of Molecular Endocrinology, Division of Cellular and Molecular Research, National Cancer Centre of Singapore, Singapore 169610, Singapore.
Ng
Chuan Young
CY
Ong
Choon Kiat
CK
Ng
Chee Pang
CP
Ma
Zeng Shuan
ZS
Nguyen
Thanh Hung
TH
Tay
Sun Kuie
SK
Huynh
Hung
H
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D001483:Base Sequence; D002450:Cell Communication; D002455:Cell Division; D002465:Cell Movement; D002879:Chromosomes, Human, Pair 10; D003001:Cloning, Molecular; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010051:Ovarian Neoplasms / Q000378:metabolism; D010053:Ovary / Q000378:metabolism; D020033:Protein Isoforms; D014162:Transfection
C488236:CUZD1 protein, human; D004967:Estrogens; D008565:Membrane Proteins; D020033:Protein Isoforms