A 42-kDa glycoprotein from chicken egg-envelope, an avian homolog of the ZPC family glycoproteins in mammalian Zona pellucida. Its first identification, cDNA cloning and granulosa cell-specific expression.
A glycoprotein with molecular mass of 42 kDa was identified as the major component of the chicken egg-envelope, the filamentous, extracellular matrix known as the perivitelline layer. By using a DNA probe amplified with degenerative primers derived from the protein's partial amino acid sequences, a cDNA clone encoding the egg-envelope 42-kDa glycoprotein (gp42) was isolated from a hen's ovary cDNA library. The gp42 open reading frame encoded 435 amino acid residues, including a putative signal peptide of 20 amino acids. The deduced amino acid sequence of gp42 showed significant similarity to egg-envelope glycoproteins of the ZPC family of several other vertebrate species, including human ZP3, mouse ZP3, Xenopus laevis gp43 and medaka (Oryzias latipes) ZI3 (LS-F), which play important roles for sperm-egg interaction. A single N-glycosylation site present in chicken gp42 is conserved among all five of these proteins: carbohydrate analysis of gp42 revealed the presence of a complex type glycan chain at this site. N-terminal sequence analysis of the mature polypeptide suggests that C-terminal processing of the pro-protein occurs during synthesis and secretion. The 1.4-kb gp42 transcript was detected only in follicles, and was found to be accumulated in granulosa cells in a manner dependent on ovarian follicular development. Furthermore, a metabolically radio-labeled gp42 was immunopreciptated from both cell lysate and culture supernatant of the granulosa cells with specific anti-gp42 antibody, suggesting granulosa cell-specific synthesis and secretion of the glycoprotein.
Takeuchi
Y
Y
Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Japan.
Nishimura
K
K
Aoki
N
N
Adachi
T
T
Sato
C
C
Kitajima
K
K
Matsuda
T
T
D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D002645:Chickens; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis; D004527:Egg Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D005260:Female; D015870:Gene Expression; D006023:Glycoproteins / Q000235:genetics* / Q000302:isolation & purification; D006107:Granulosa Cells / Q000737:chemistry; D006801:Humans; D008562:Membrane Glycoproteins / Q000737:chemistry; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010063:Ovum / Q000737:chemistry*; D011956:Receptors, Cell Surface; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D000072216:Zona Pellucida Glycoproteins
D018076:DNA, Complementary; D004527:Egg Proteins; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; C000606517:ZP3 protein, human; D000072216:Zona Pellucida Glycoproteins; C000606521:Zp3 protein, mouse