Effectiveness of an immunocastration vaccine formulation to reduce the gonadal function in female and male mice by Th1/Th2 immune response.

Immunocastration has emerged as an alternative to surgical castration in different animal species. This study examined the effectiveness of a new vaccine formulation for immunocastration using the biopolymer chitosan as adjuvant. First, female and male mice (n = 4), in three subsequent experiments were vaccinated at Days 1 and 30 of the study, to determine the immune response profile and gonadal alterations due to immunization. The results demonstrated that the vaccine was able to elicit strong antibody responses against native GnRH hormone (P < 0.01), with a T helper (Th) 1/Th2 immune response profile. Along with this, a suppression of gonadal activity with a decrease of luteal bodies (1.08 ± 0.22 and 4.08 ± 0.39) and antral follicles (1.17 ± 0.32 and 4.5 ± 0.38) in the ovaries of immunized females and control, respectively, and a reduction of seminiferous tubules size (142.3 ± 5.58 mm and 198.0 ± 6.11 mm) and germinal cellular layers (3.58 ± 0.26 and 5.08 ± 0.29) of immunized males and control animals, respectively, were observed (P < 0.01). Then, in a study of long-term immune response due to vaccination in female and male mice (n = 4) from two subsequent experiments, a suppression of gonadal function and an induction of a Th1/Th2 immune response was also observed, determined by both, immunoglobulin and cytokine profiles, which lasted until the end of the study (7 months; P < 0.01). The findings of this study have demonstrated that vaccination with a new immunocastration vaccine inducing a Th1/Th2 immune response against GnRH (P < 0.01) elicit a decrease of gonadal function in male and female mice (P < 0.01). Owing to long-term duration of the antibody levels generated, this vaccine formulation appears as a promising alternative for immunocastration of several animal species where long-lasting reproductive block is needed.

Restriction fragment length analysis of the cytochrome b gene and muscle fatty acid composition differentiate the cryptic flatfish species Solea solea and Solea aegyptiaca.

Overlapping external morphometric characters easily confound the flatfishes Solea aegyptiaca and Solea solea (Soleidae) in areas of the Mediterranean Sea where both species live in sympatry. This leads to uncertainties in the fisheries and marketing of the species, in addition to misinterpretations in biogeography and conservation studies. This paper describes a simple restriction fragment length-based diagnostic test that differentiates S. solea from S. aegyptiaca, as well as from other species of the Soleidae family. Furthermore, the two species living in sympatry in the Gulf of Kavala (North Aegean Sea, Greece) present significant qualitative differences in muscle fatty acid composition, a property that can also be used to distinguish the two cryptic species.

Evolutionary history of the genus Trisopterus.

The group of small poor cods and pouts from the genus Trisopterus, belonging to the Gadidae family, comprises four described benthopelagic species that occur across the North-eastern Atlantic, from the Baltic Sea to the coast of Morocco, and the Mediterranean. Here, we combined molecular data from mitochondrial (cytochrome b) and nuclear (rhodopsin) genes to confirm the taxonomic status of the described species and to disentangle the evolutionary history of the genus. Our analyses supported the monophyly of the genus Trisopterus and confirmed the recently described species Trisopterus capelanus. A relaxed molecular clock analysis estimated an Oligocene origin for the group (~30 million years ago; mya) indicating this genus as one of the most ancestral within the Gadidae family. The closure and re-opening of the Strait of Gibraltar after the Messinian Salinity Crisis (MSC) probably triggered the speciation process that resulted in the recently described T. capelanus.

Nna1-like proteins are active metallocarboxypeptidases of a new and diverse M14 subfamily.

Nna1 has some sequence similarity to metallocarboxypeptidases, but the biochemical characterization of Nna1 has not previously been reported. In this work we performed a detailed genomic scan and found >100 Nna1 homologues in bacteria, Protista, and Animalia, including several paralogs in most eukaryotic species. Phylogenetic analysis of the Nna1-like sequences demonstrates a major divergence between Nna1-like peptidases and the previously known metallocarboxypeptidases subfamilies: M14A, M14B, and M14C. Conformational modeling of representative Nna1-like proteins from a variety of species indicates an unusually open active site, a property that might facilitate its action on a wide variety of peptide and protein substrates. To test this, we expressed a recombinant form of one of the Nna1-like peptidases from Caenorhabditis elegans and demonstrated that this protein is a fully functional metallocarboxypeptidase that cleaves a range of C-terminal amino acids from synthetic peptides. The enzymatic activity is activated by ATP/ADP and salt-inactivated, and is preferentially inhibited by Z-Glu-Tyr dipeptide, which is without precedent in metallocarboxypeptidases and resembles tubulin carboxypeptidase functioning; this hypothesis is strongly reinforced by the results depicted in Kalinina et al. published as accompanying paper in this journal. Our findings demonstrate that the M14 family of metallocarboxypeptidases is more complex and diverse than expected, and that Nna1-like peptidases are functional variants of such enzymes, representing a novel subfamily (we propose the name M14D) that contributes substantially to such diversity.