Cloning of cDNAs for the Precursor Protein of a Low-Molecular-Weight Subunit of the Inner Layer of the Egg Envelope (Chorion) of the Fish Oryzias latipes

Abstract

cDNA clones for L-SF, the precursor of a low-molecular-weight subunit (ZI-3) of the inner layer of the Oryzias latipes egg envelope were isolated from Lambda ZAP cDNA libraries constructed from the poly(A)+ RNA of the liver of spawning female fish and estrogen-treated male fish. Among them, a clone, L-SF41, is 1473 bp long and contains an open reading frame encoding a signal peptide of 19 amino acids and L-SF protein of 420 amino acids. L-SF protein seems to be glycosylated, judging from the result of the glycanase digestion. L-SF protein contains a domain similar to ZP-domains in ZP3 of some mammalian species. Northern blot analysis employing XhoI-SmaI fragments of the cloned cDNA as probes revealed that expression of the L-SF gene occurred exclusively in the livers of spawning female fish and estrogen-treated male fish and that there was no mRNA encoding L-SF in the ovary of the spawning female fish.

Molecular characterization and expression pattern of three zona pellucida 3 genes in the Chinese sturgeon, Acipenser sinensis

“…We detected the expression of all three AsZP3s in the testes of two 3-year-old male individuals (Fig. 5), while the earlier observations have found the liver of male fish can synthesize ZP proteins induced by estradiol (Murata et al 1995). So fish ZP3 genes may display a wide tissue distribution other than ovary and liver.…”

“…For instance, medaka (Murata et al 1995), rainbow trout (Hyllner et al 2001), and gilthead seabream (Del Giacco et al 1998) synthesized ZP3 protein in liver, which is in contrast to chickens, mice, Xenopus, crucian carp, goldfish, common carp, and zebrafish. In chickens, synthesis occurs in granulose cells (Waclawek et al 1998); whereas in mouse, Xenopus, and crucian carp, it occurs in the oocyte (Fan et al 2001;Yamaguchi et al 1989;Waclawek et al 1998).…”

“…Since fish ZP3 cDNA molecules were first characterized in medaka, Oryzias latipes (Murata et al 1995), cDNA cloning and sequencing of ZP3 have been reported in a number of fish species, such as gilthead sea bream, Sparus aurata (Del Giacco et al 1998;Modig et al 2006), zebrafish, Danio rerio (Wang and Gong 1999;Del Giacco et al 2000), common carp, Cyprinus carpio (Chang et al 1996), gyno-crucian and gono-crucian carp (Fan et al 2001), rainbow trout, Oncorhynchus mykiss (Hyllner et al 2001), and half-smooth tongue sole, Cynoglossus semilaevis (Sun et al 2010). In recent years, based on available genome sequence and subtractive cDNA libraries, more ZP3 gene isoforms were characterized.…”

Differential screening and characterization analysis of the egg envelope glycoprotein ZP3 cDNAs between gynogenetic and gonochoristic crucian carp

“…In mammals, ZP3 is also synthesized in the growing oocytes and constitutes the egg envelope from the inside of the oocytes [4]. In contrast with crucian carp and mammals, however, ZP3 of another fish medaka ( Oryzias latipes) is synthesized only in liver but not in ovary of spawning female fish [38]. As shown by Waclawek et al, the chicken ZP3 is expressed exclusively in the granulosa cells surrounding oocytes [39].…”

“…A search of GeneBank database revealed that the ZP3 amino acid sequences of gyno-and gonocarp were homologous to that of the egg envelope glycoprotein ZP3 isolated from common carp [33], zebrafish [37], medake [38], Xenopus [31] and chicken [39], [40] and of mammalian zona pellucida ZP3 isolated from mouse [41] and human [42]. The level of sequence identity was found to be highly significant among a variety of fish species.…”