Assignment of chromosomal locus and evidence for alternatively spliced mRNAs of a human sperm membrane protein (hSMP-1).
The gene (HSD-1) coding a human sperm membrane protein (hSMP-1) was isolated from a human testis cDNA expression library using antibodies found in the serum of an infertile woman. HSD-1 was localized to a single locus on chromosome 9 and assigned to band 9p12-p13 by fluorescent in situ hybridization (FISH) mapping and DAPI (4,6-diamidino-2-phenylindole) banding, using rat/human somatic cell hybrids and metaphase chromosomes of human lymphocytes. In rescreening a testis lambdagt10 cDNA expression library, the full-length cDNA (HSD-1) and several truncated cDNAs with heterologous regions were isolated from positive clones. The heterology consisted of deletion, insertion and alteration of the 5'-end. These heterologous truncated fragments may be produced by alternative splicing of mRNAs. Two recombinant prokaryotic expression vectors were constructed with one of the heterologous fragment (clone #26) with and without the alternative 5'-end. Escherichia coli transfected with the construct containing the alternative 5'-end failed to produce the recombinant product, whereas those transfected with the vector lacking the 5'-end produced hSMP-1. DNASIS analysis of the structure of #26 mRNA suggests that the 5'-end has a stable secondary configuration that may maintain the mRNA in an inactivated state, whereby hindering its translation and preventing the expression of the gene.
Wang
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National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Faculty of Basic Medicine, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, PR China.
Miao
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Chen
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Wang
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Koide
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D000595:Amino Acid Sequence; D000954:Antigens, Surface; D001483:Base Sequence; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D016384:Consensus Sequence; D018076:DNA, Complementary / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics; D015723:Gene Library; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008214:Lymphocytes / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D013737:Testis / Q000378:metabolism; D014162:Transfection
D000954:Antigens, Surface; D018076:DNA, Complementary; D008565:Membrane Proteins; D012333:RNA, Messenger; C099014:SPAG8 protein, human