The farther the better: Investigating how distance from human self affects the propensity of a peptide to be presented on cell surface by MHC class I molecules, the case of Trypanosoma cruzi.

More than twenty years ago the reverse vaccinology paradigm came to light trying to design new vaccines based on the analysis of genomic information in order to select those pathogen peptides able to trigger an immune response. In this context, focusing on the proteome of Trypanosoma cruzi, we investigated the link between the probabilities for pathogen peptides to be presented on a cell surface and their distance from human self. We found a reasonable but, as far as we know, undiscovered property: the farther the distance between a peptide and the human-self the higher the probability for that peptide to be presented on a cell surface.

Expression pattern of zebrafish rxfp2 homologue genes during embryonic development.

RXFP2 is one of the 4 receptors for relaxin insulin-like peptides, in particular it binds with high affinity the INSL3 peptide. INSL3/RXFP2 pair is essential for testicular descent during placental mammalian development. The evolutionary history of this ligand/receptor pair has received much attention, since its function in vertebrate species lacking testicular descent, such as the fishes, remains elusive.

Expression analysis of five zebrafish RXFP3 homologues reveals evolutionary conservation of gene expression pattern.

Relaxin peptides exert different functions in reproduction and neuroendocrine processes via interaction with two evolutionarily unrelated groups of receptors: RXFP1 and RXFP2 on one hand, RXFP3 and RXFP4 on the other hand. Evolution of receptor genes after splitting of tetrapods and teleost lineage led to a different retention rate between mammals and fish, with the latter having more gene copies compared to the former. In order to improve our knowledge on the evolution of the relaxin ligands/receptors system and have insights on their function in early stages of life, in the present paper we analyzed the expression pattern of five zebrafish RXFP3 homologue genes during embryonic development.

Developmental expression pattern of two zebrafish rxfp3 paralogue genes.

In mammals, the RXFP3 is the cognate receptor of the relaxin-3 peptide (RLN3). In teleosts, many different orthologue genes for RXFP3 are present. In particular, two paralogue genes, rxfp3-2a and rxfp3-2b, likely encode the receptors for the Rln3a peptide.

A network system for vitellogenin synthesis in the mussel Mytilus galloprovincialis (L.).

The aim of this study is to assess, by RT-PCR, in situ hybridization, electron microscopy, and immunohistochemistry, the site/s of vitellogenin (VTG) synthesis in the mussel Mytilus galloprovincialis. Our investigations demonstrate that, among the analyzed tissues, the synthesis of VTG occurs only in the female gonad, that is, within the oocyte and follicle and connective cells. Such a synthesis is just evident in early vitellogenic oocytes, whose cytoplasm is characterized by numerous RER cisternae and an extended Golgi complex surrounded by nascent yolk platelets.

Characterization, cDNA cloning and expression pattern of relaxin gene during embryogenesis of Danio rerio.

We report the identification, the cDNA cloning, the temporal and spatial expression pattern analysis of the rln gene in the zebrafish Danio rerio. The deduced Rln B and A domains show different evolutionary conservation. Rln B domain shows higher similarity when compared to zebrafish and human RLN3 B domain than human RLN1 and RLN2 B domain.

Design and production of a chimeric resilin-, elastin-, and collagen-like engineered polypeptide.

Protein-inspired biomaterials have gained great interest as an alternative to synthetic polymers, in particular, for their potential use as biomedical devices. The potential inspiring models are mainly proteins able to confer mechanical properties to tissues and organs, such as elasticity (elastin, resilin, spider silk) and strength (collagen, silk). The proper combination of repetitive sequences, each of them derived from different proteins, represents a useful tool for obtaining biomaterials with tailored mechanical properties and biological functions.

Characterization and developmental expression pattern of the relaxin receptor rxfp1 gene in zebrafish.

We report the gene characterization, the cDNA cloning and the temporal and spatial expression pattern of the relaxin receptor rxfp1 gene in the zebrafish Danio rerio. The zebrafish rxfp1 gene has the same syntenic genomic organization, and a similar exon-intron structure to the homologue human gene. Furthermore, the deduced Rxfp1 protein sequence shows a high degree of amino acid similarity when compared with the human protein and the conservation of all amino acid identity necessary for the binding with relaxin.

Evidence of genetic instability in tumors and normal nearby tissues.

Background: Comprehensive analyses have recently been performed on many human cancer tissues, leading to the identification of a number of mutated genes but providing no information on the variety of mutations present in each of them. This information is of interest to understand the possible origin of gene mutations that cause tumors.

Methodology/principal Findings: We have analyzed the sequence heterogeneity of the transcripts of the human HPRT and G6PD single copy genes that are not considered tumor markers.

Differential expression of duplicated genes for prothymosin alpha during zebrafish development.

We show that ptma, a single copy gene found in all organisms investigated so far, is duplicated in zebrafish. The two genes, ptmaa and ptmab, are individually controlled as indicated by their different expression patterns during embryonic development. Only the ptmab transcript is observed at 4 and 8 hpf of development in all embryonic cells, whereas both genes are expressed at later stages as revealed by in situ hybridization studies.

A possible flip-flop genetic mechanism for reciprocal gene expression.

Innexins are a family of transmembrane proteins involved in the formation of gap junctions, specific intercellular channels, in invertebrates. Analyses of the entire innexin family during Drosophila melanogaster embryonic development shows the occurrence of complex and specific patterns of expression of the different genes. Innexins inx-2 and inx-7, in general, do not appear to exhibit extensive co-expression in different D.

The expression of de novo DNA methylase DNMT3b, of the methyl-CpG binding protein MBD2b and of 5-MCDG glycosylase shows two waves of induction during CaCO-2 cell differentiation.

DNA methylation plays a central role in the control of gene expression during development and cell differentiation, thus DNA methylation and demethylation processes are expected to be strictly regulated during these events. We have explored the expression levels of the genes encoding DNA methylases, methyl-CpG binding proteins and demethylases during in vitro differentiation of human carcinoma colon cells (CaCO-2) used as a model system. The results show that the global DNA methylation pattern remains constant during CaCO-2 cells differentiation indicating that required genome methylation pattern in cell differentiation was already established in the seeded cells.

Specificity of cellular expression of C. variopedatus polychaete innexin in the developing embryo: evolutionary aspects of innexins' heterogeneous gene structures.

Innexins are a family of membrane proteins involved in the formation of gap junctions in invertebrates. They have been found to participate in several aspects of cell differentiation and in embryonic patterning through the formation of specific intercellular communication channels. We present here data showing that the recently identified innexin of the marine worm Chaetopterus variopedatus is expressed only in particular cells of the early stage, demonstrating cell specificity of innexin expression also in polychaete annelids.

Cloning and molecular characterization of the first innexin of the phylum annelida-expression of the gene during development.

A novel member of the innexin family (cv-inx) has been isolated from the annelid polychaete worm Chaetopterus variopedatus using a PCR approach on genomic DNA and sequence analysis on genomic DNA clones. The gene is present in a HindIII-HindIII segment of 2250 bp containing an uninterrupted open reading frame of 1196 bp encoding a protein of 399 amino acids. The predicted protein shows the typical structural features of innexins and consensus sites for phosphorylation.