title: Identification of a rabbit epididymal protein gene.
abstract: A protein designated as BE-20 was purified from cauda epididymal fluid of the rabbit by preparative polyacrylamide gel electrophoresis and HPLC on a mono Q HR5/5 anion exchange column. The purified protein migrated with an estimated Mt of 20,000 when analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The amino acid sequence of the N-terminus of the BE-20 protein was determined. The initial eight amino acid residues were His-Gly-Ala-Asp-Lys-Pro-Gly-Val. The corresponding 23 mer oligonucleotide (5'-CATGGCGCTGACAAGCCTGGGGT-3') was synthesized and used as sense primer with rabbit epididymal mRNA as template in the RT-PCR system. The purified BE-20 cDNA consisted of 499 bp with an open reading frame of 285 bp encoding a deduced polypeptide composed of 95 amino acids. The BE-20 cDNA had 78.5% identity in 479 bp overlap with human epididymis-specific HE4 cDNA. The amino acid sequences of the initial 30 amino acid residues of the N-terminus of the purified protein and the deduced polypeptides were as follows: N-His-Gly-Ala-Asp-Lys-Pro-Gly-Val-Cys-Pro-Gln-Leu-Ser-Ala-Asp-Leu-Asn-Cy s- Thr-Gln-Asp-Cys-Arg-Ala-Asp-Gln-Asp-Cys-Ala-Glu. The deduced polypeptide contained 16 cysteine residues and had partial sequence homology with proteins belonging to the four-disulfide core family of extracellular proteinase inhibitors. The BE-20 protein may play a role in sperm maturation and/or capacitation.
authors.affiliation: National Laboratory of Medical Molecular Biology, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.
authors.forename: W D
authors.initials: WD
authors.lastname: Xu
authors.forename: L F
authors.initials: LF
authors.lastname: Wang
authors.forename: S Y
authors.initials: SY
authors.lastname: Miao
authors.forename: M
authors.initials: M
authors.lastname: Zhao
authors.forename: H Y
authors.initials: HY
authors.lastname: Fan
authors.forename: S D
authors.initials: SD
authors.lastname: Zong
authors.forename: Y W
authors.initials: YW
authors.lastname: Wu
authors.forename: X Q
authors.initials: XQ
authors.lastname: Shi
authors.forename: S S
authors.initials: SS
authors.lastname: Koide
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins; D017931:DNA Primers / Q000138:chemical synthesis; D018076:DNA, Complementary / Q000737:chemistry; D004822:Epididymis / Q000737:chemistry*; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D011817:Rabbits; D017421:Sequence Analysis; D017385:Sequence Homology; D013735:Testicular Hormones / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D060589:Zyxin
chemical_list: D003598:Cytoskeletal Proteins; D017931:DNA Primers; D018076:DNA, Complementary; D006023:Glycoproteins; D013735:Testicular Hormones; C092842:ZYX protein, human; D060589:Zyxin