Identification and spatial distribution of the mRNA encoding the gp49 component of the gilthead sea bream, Sparus aurata, egg envelope

Abstract

A cDNA encoding the precursor of one of the major components of gilthead sea bream, Sparus aurata, egg envelope has been cloned by reverse transcriptase polymerase chain reaction (RT-PCR) techniques. The clone was isolated starting from total RNA extracted from the liver of spawning female fish and estradiol-17 beta-treated male fish. Sequence analysis revealed that the cDNA encoded a protein of 405 aa corresponding to 49-kDa component (termed gp49), a glycoprotein belonging to the N-linked type. The gp49 protein is homologous to the Zl-3 of medaka Oryzias latipes, the mammalian ZPC and ZPC homologues of Xenopus laevis (xlZPC) and carp Cyprinus carpio (ccZPC). In addition, the open reading frame also encodes an additional aa sequence, the signal peptide, located in the N-terminal region of the protein. RT-PCR and in situ expression analyses evidenced an organ-restricted pattern: the mRNA was detected only in liver of spawning female and estradiol-17 beta-treated male fish but not in other tissues.

The Major Chicken Egg Envelope Protein ZP1 Is Different from ZPB and Is Synthesized in the Liver

“…4A), even after prolonged exposure of the films to the blots (data not shown). This expression pattern resembles the one observed in teleost fish (25)(26)(27)(28)(29), but is in contrast to the one reported for other vertebrate ZP1/ZPB homologues (cf. Refs.…”

“…The (27), medaka (29,45), carp (46), gilthead sea bream (28), and zebrafish (47). It has been hypothesized that the function of these motifs is to assist in the hardening of the egg envelope after fertilization (47), but this theory remains speculative.…”

Transgene driving GFP expression from the promoter of the zona pellucida gene zpc is expressed in oocytes and provides an early marker for gonad differentiation in zebrafish

“…Similar to endogenous zpc mRNA (Del Giacco et al, 1998; this work), zpc0.5:GFP transgene-derived GFP is most strongly expressed in stage I oocytes (Fig. 2C,D).…”

Differential Lectin Binding Patterns Identify Distinct Heart Regions in Giant Danio ( Devario aequipinnatus ) and Zebrafish ( Danio rerio ) Hearts

“…We selected a panel of plant-based lectins most commonly used in functional, histological, and biochemical studies of mammalian 29,30,40,41 and non-mammalian 36,42,43 hearts. As lectins recognize specific carbohydrate moieties on membrane, cytosolic, and extracellular glycoconjugates, and different lectins can bind the same carbohydrate moieties, they can be categorized into specificity groups.…”