Vh. Lee et al., IDENTIFICATION AND STRUCTURAL CHARACTERIZATION OF THE 75-KDA RABBIT ZONA-PELLUCIDA PROTEIN, The Journal of biological chemistry, 268(17), 1993, pp. 2412-2417
A cDNA (rc75) encoding a 75-kDa rabbit zona pellucida (ZP) glycoprotei
n (R75) has been cloned and sequenced. The predicted amino acid sequen
ce consists of 676 amino acids including seven potential N-glycosylati
on sites. The cDNA hybridizes to a 2.4-kilobase mRNA in ovary that is
not detectable in other rabbit tissues. The R75 mRNA was also found to
be expressed during the early stages of rabbit ovarian development (2
-6 weeks of age) when the ovary contains primordial, primary, and earl
y secondary follicles. The deduced amino acid sequence of rc75 has 77%
similarity to the mouse ZP2 protein but no similarity to mouse ZP3. R
75 also contains regions with 35-55% similarity to a previously cloned
rabbit 55-kDa ZP protein. Monte Carlo simulation comparison confirmed
that R75 has a significant probability of homology with mouse ZP2 and
the rabbit 55-kDa ZP protein. Antibodies were developed against a fra
gment of R75 (rc75a cDNA) expressed in the pEX expression vector. Thes
e antibodies were used to confirm that the expressed protein contained
epitopes found in the native rabbit ZP glycoprotein. These data sugge
st that some, but not all, ZP proteins may be conserved among differen
t species and that within a species ZP proteins may share similar regi
ons.