Molecular cloning of epididymal and seminal vesicular transcripts encoding a semenogelin-related protein.
Freshly ejaculated human semen has the appearance of a loose gel in which the predominant structural protein components are the seminal vesicle-secreted semenogelins (Sg). The primary structure of the 439-residue SgI has previously been obtained by cDNA cloning. This cDNA cross-hybridizes to a larger transcript coding for a second secretory protein, SgII. Here we report the almost complete structure of a precursor of SgII established by lambda gt11 clones isolated from epididymal and seminal vesicular cDNA libraries. The deduced amino acid sequence of the 559-residue mature protein has a molecular weight of 62,931 but an increase in weight may be provided by asparagine-linked oligosaccharide attachment at residue 249. SgII, which has 78% overall identity with SgI, contains eight 60-residue regions that display conspicuous internal sequence similarity, whereas SgI only contains six of these regions. The SgII structure is translated from an open reading frame in a polyadenylylated 2.4-kilobase transcript. The message is abundant in the seminal vesicles but rare in the epididymis.
Lilja
H
H
Department of Clinical Chemistry, Lund University, Malmö General Hospital, Sweden.
Lundwall
A
A
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular / Q000379:methods; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004822:Epididymis / Q000502:physiology*; D015723:Gene Library; D012739:Gonadal Steroid Hormones / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009838:Oligodeoxyribonucleotides; D011498:Protein Precursors / Q000235:genetics*; D015183:Restriction Mapping; D012661:Semen / Q000502:physiology*; D029589:Seminal Plasma Proteins; D029607:Seminal Vesicle Secretory Proteins; D012669:Seminal Vesicles / Q000502:physiology*; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D012739:Gonadal Steroid Hormones; D009838:Oligodeoxyribonucleotides; D011498:Protein Precursors; D029589:Seminal Plasma Proteins; D029607:Seminal Vesicle Secretory Proteins; C424482:seminal vesicle-specific antigen; D004247:DNA