Identification of a cDNA clone encoding DIP1-binding protein in Drosophila melanogaster

The Drosophila melanogaster L27a gene encodes a ribosomal protein which is a member of the L15 family of ribosomal proteins. D.m. L27a is closely related to the mammalian protein that has been found differentially expressed in lung cancer tissues and therefore could be involved in the control of cell proliferation such as the ribosomal protein S6. Our work elucidates the role of DIP1 which is a novel protein that we found in Drosophila. We performed a two-hybrid system assay and identified the L27a protein as an interactor of DIP1. The interaction was then validated by in vitro binding assays. DIP1, similar to other nuclear proteins in eukaryotes, is localized to the nuclear periphery and chromatin domain in all nuclei, but disappears at the metaphase. It is possible that in D.m. L27a protein, via interaction with DIP1, could be involved in protein synthesis as well as in cell cycle regulation. © 2004 Kluwer Academic Publishers

PLANT GENES FOR ABIOTIC STRESS

"Abiotic stress is the primary cause of crop loss worldwide, reducing average yields for most major crop plants by more than 50%. Plants as sessile organisms are constantly exposed to changes in environmental conditions. When these changes are rapid and extreme, plants generally perceive them as stresses. However stresses are not necessarily a problem for plants because they have evolved effective mechanisms to avoid or reduce the possible damages.

Molecular characterization and expression of p63 isoforms in human keloids

Keloids are benign skin tumors that develop following wounding. A cDNA product from human keloid specimens was identified using the differential display technique. The full-length cDNA was cloned by RT-PCR using human keloid mRNA as template. The predicted product of the cDNA was found to be 99% identical to the ΔN-p63 gamma isotype of p63, a transcription factor that belongs to the family that includes the structurally related tumor suppressor p53 and p73. The ΔN-p63 isotype lacks the acidic N terminal region corresponding to the transactivation domain of p53. Since this can potentially block p53-mediated target gene transactivation, it may serve as a dominant-negative isoform. Real-Time RT-PCR analysis of RNAs from normal skin tissue and keloids showed that the ΔN-p63 isotype is specifically expressed in keloids, but is virtually undetectable in normal skin. Immunostaining of p63 in normal skin revealed that only basal cells of the epithelium expressed the protein, while in keloid tissues the antigen was detected in the nuclei of cells scattered through all layers of the epithelium and in fibroblast-like cells in the dermis. These results may indicate that aberrant p63 expression plays a role not only in malignant tumors but also in benign skin diseases that show hyperproliferation of epidermal cells in vivo. Moreover, this isoform of p63 could serve as a specific molecular marker for this human disease.Keloids are benign skin tumors that develop following wounding. A cDNA product from human keloid specimens was identified using the differential display technique. The full-length cDNA was cloned by RT-PCR using human keloid mRNA as template. The predicted product of the cDNA was found to be 99% identical to the DeltaN-p63 gamma isotype of p63, a transcription factor that belongs to the family that includes the structurally related tumor suppressor p53 and p73. The DeltaN-p63 isotype lacks the acidic N terminal region corresponding to the transactivation domain of p53. Since this can potentially block p53-mediated target gene transactivation, it may serve as a dominant-negative isoform. Real-Time RT-PCR analysis of RNAs from normal skin tissue and keloids showed that the DeltaN-p63 isotype is specifically expressed in keloids, but is virtually undetectable in normal skin. Immunostaining of p63 in normal skin revealed that only basal cells of the epithelium expressed the protein, while in keloid tissues the antigen was detected in the nuclei of cells scattered through all layers of the epithelium and in fibroblast-like cells in the dermis. These results may indicate that aberrant p63 expression plays a role not only in malignant tumors but also in benign skin diseases that show hyperproliferation of epidermal cells in vivo. Moreover, this isoform of p63 could serve as a specific molecular marker for this human disease

A PCR based SNPs marker for specific characterization of English walnut (Juglans regia L.) cultivars

English walnut (Juglans regia L.) is the most economically important species from all the 21 species belonging to the genus Juglans and is an important and healthy food as well as base material for timber industry. The aim of this study was to develop a simple technique for specific characterization of English walnut using DNA method. The first and second internal transcribed spacers (ITS1 and ITS2) as well as the intervening 5.8S coding region of the rRNA gene for 18 cultivars of J. regia L. isolated from different geographic origins were characterized. The size of the spacers sequences ranged from 257 to 263 bases for ITS1 and from 217 to 219 bases for ITS2. Variation of GC contents has also been observed and scored as 55-56.7 and 57.1-58.9% for ITS1 and ITS2, respectively. This data exhibited the presence of polymorphism among cultivars. Alignment of the ITS1-5.8S-ITS2 sequences from 18 walnut cultivars showed that there were 244 single nucleotide polymorphisms (SNPs) and 1 short insertion-deletion (indel) at 5′ end ITS1. Amplification refractory mutation system strategy was successfully applied to the SNP markers of the ITS1 and ITS2 sequences for the fingerprinting analysis of 17 on 18 walnut cultivars. The prediction of ITS1 and ITS2 RNA secondary structure from each cultivar was improved by detecting key functional elements shared by all sequences in the alignments. Phylogenetic analysis of the ITS1-5.8S-ITS2 region clearly separated the isolated sequences into two clusters. The results showed that ITS1 and ITS2 region could be used to discriminate these walnut cultivars. © 2010 Springer Science+Business Media B.V

Ty1-copia group retrotransposons and the evolution of retroelements in several angiosperm plants: evidence of horizontal transmission.

"The phylogenetic relationships among thirty-seven new Ty1-copia group retrotransposons in seven angiosperm plants were examined by reverse transcriptase and ribonuclease H sequence analysis. Distribution pattern of the retrotransposons of closely related plant species generally reflects a close phylogenetic relationship. In contrast, we found that several retrotransposon sequences from the same genome exhibited a high degree of divergence and had a relatively high degree of identity versus retrotransposon sequences from widely divergent species, including an ancestral phytopathogen fungus. This finding supports the hypothesis that the horizontal transmission from phytopatogen organism to the host flowering plants could have played a role in the evolutionary dynamics of Ty1-copia group retrotransposons.

Glutathione-Ascorbate cycle and lipid peroxidation in fruit of sweet cherry landraces of Campania region (Italy). XIV FISV CONGRESS Book of abstracts, Rome (Italy).

Fresh fruits are living organs that continue their metabolism even after harvest. The advanced stages of ripening culminate into the senescence process, that eventually leads to the death of fruit. Several works highlight the importance of antioxidant metabolism in relation to the fruit quality and shelf-life: fruit ripening is accompanied by a progressive increase in oxidative stress that is controlled by a related induction of the antioxidant scavenging systems. Dysfunctioning of such systems in the later stages of ripening causes an increase of oxidation, that is among the most important factors of fruit decay, favouring also parasite attack and development. High antioxidant metabolite levels, in fact, could delay senescence and preserve nutritional and nutraceutical characteristics, significantly reducing fruit loss and cost. Sweet cherries fruits are excellent sources of phytochemicals: nutraceuticals and antioxidants. It has been demonstrated that the eating of cherries reduces the risk of cancer and the joint pains, and protects from cardiovascular and neurodegenerative diseases. The aim of this work was to characterize glutathione-ascorbate cycle as well as lipid peroxidation in mature fruits of the sweet cherry germoplasm of Campania region and their involvment in post harvest storage. Fruits from cherry landraces of Campania region were collected at commercial maturity and used for the analyses. Glutathione as ascorbate contents differed among the landraces as welle as glutathione reductase. Differences were also found in the lipid peroxidation activities using the MDA test. . the data of glutathione level and redox state and gluthione peroxidase, ascorbate level and redox state as ascorbate peroxidase activities, tocophrols and polyphenols, two groups of landraces have been evidenced. The first showed high polyphenol oxidases activities, that could indicate a higher risk of developing oxidative stress and, consequently, a higher susceptibility to the oxidative degradation during shelf-life. The second showed high ascorbic acid and tocopherols contents, and low polyphenol oxidase activities. The high metabolites concentration could reduce the risk of oxidative damages during storage, therefore they could show a longer shelf-life than the other tested fruits. These characteristics were probably due to endogenous characteristics, making these landraces particularly interesting for breeding programs aimed to improve sweet cherry shelflife, highlighting also the value of genetic heritage of sweet cherry of Campania region

Hordeum vulgare and Hordeum maritimum respond to extended salinity stress displaying different temporal accumulation pattern of metabolites

Hordeum maritimum With. (= H. marinum Huds. subsp. marinum, 2n = 14) is a wild cereal present in the saline depressions of the Soliman and Kelbia Sebkhas, which contributes significantly to annual biomass production in Tunisia. This species is able to tolerate high NaCl concentrations at the seedling stage without showing symptoms of toxicity; however, the tolerance strategy mechanisms of this plant have not yet been unravelled. Our metabolite analysis, performed on leaves of H. maritimum during extended stress in comparison with Hordeum vulgare L. cv. Lamsi, has revealed an adaptive response of the wild species based on a different temporal accumulation pattern of ions and compatible metabolites. Further, wild and cultivated genotypes with contrasting salt-tolerant behaviour display different pattern of metabolites when salt stress is prolonged over 2 weeks. In particular, when exposed to up to 3 weeks of 200 mM NaCl salt stress, H. maritimum is able to maintain lower leaf concentrations of sodium and chloride, and higher concentrations of potassium compared with H. vulgare. This likely restricts sodium entry into plants at the root level, and uses the toxic ions, glycine betaine and low levels of proline for osmotic adjustment. Under prolonged stress, the accumulation of proline increases, reaching the highest levels in concomitance with the decrease of potassium to sodium ratio, the increase of hydrogen peroxide and decrease of chlorophylls. The modulation of proline accumulation over time can be interpreted as an adaptive response to long-term salinity. Moreover, once synthetised glycine betaine is transported but not metabolised, it can contribute together with proline to osmotically balance H. maritimum leaves and protect them from oxidative stress. The 2-3 week delay of H. maritimum in showing the symptoms of stress and damages compared with IL vulgare could be important in the survival of plants when soil salinity is not a permanent condition, but just a transient state of stress

Use of Nuclear and Mitochondrial Single Nucleotide Polymorphisms to Characterize English Walnut (Juglans regia L.) Genotypes

English walnut (Juglans regia L.) is the most economically important species, for both food and timber, of the 21 species belonging to the genus Juglans. This study was undertaken to analyze and compare DNA sequences of the mitochondrial cytochrome oxidase subunit II (COX2) and ribosomal DNA (rDNA) genes in the molecular characterization of 30 English walnut genotypes. rDNA sequences revealed the presence of 402 variations, including 101 in 3′ ends of 18S, 21 in internal transcribed spacer 1(ITS1), 170 in ITS2, 30 in 5.8S, and 80 in 5′ ends of 28S regions. Cox2 intron I sequences showed 769 variable positions and GG insertion/deletion at 3′ end regions. Based on single nucleotide polymorphism markers of rDNA and cox2 intron I sequences, an amplification refractory mutation system was used to fingerprint 18 out of 30 walnut genotypes. The findings revealed that the cox2 intron I region, either alone or in conjunction with rDNA, could be used effectively in identifying these walnut genotypes. © 2013 Springer Science+Business Media New York

Differential p63 and p53 expression in human keloid fibroblasts and hypertrophic scar fibroblasts.

The p63 gene belongs to the p53 gene family and encodes for sequence-specific transcription factors. p63 has been characterized primarily in the context of epidermis where is implicated in the establishment of keratinocyte cell fate and in maintenance of epithelial self-renewal. DeltaNp63 isoform has been showed to be involved in several kinds of human tumors of epidermal origin, even nonmalignant, for the neoplastic and proliferative potential. Here, we report the differential expression and the cellular localization of the DeltaNp63 isoform in fibroblasts isolated from human keloids and hypertrophic scars compared to normal skin. Differently from hypertrophic scar, our results show that DeltaNp63 has a nuclear localization and is overexpressed only in keloid fibroblasts, suggesting an essential role of DeltaNp63 in vivo in human keloids. Consistent with our results, we hypothesize that DeltaNp63 overexpression may be oncogenic because of its ability to block the activity of p53 since p53 is underexpressed in fibroblasts from keloids