Variation of a carotenoid-based trait in relation to oxidative stress and endocrine status during the breeding season in the Eurasian kestrel: a multi-factorial study.

Carotenoid-based skin colorations vary seasonally in many bird species and are thought to be honest sexually selected signals. In order to provide more insight in the potential signal function and underlying mechanisms of such colorations we here quantified patterns of variation of leg coloration in adult male and female Eurasian kestrels (Falco tinnunculus tinnunculus) over the breeding season, and evaluated the relationship between coloration and levels of carotenoids, androgens and estrogens, oxidative damage and plasma non-enzymatic antioxidant capacity. We studied both reproducing wild and non-reproducing captive birds to test for the effect of diet and breeding effort. Males were more colored than females only during mating, and independently of diet, suggesting that leg-color is a sexually selected trait. Seasonal variation in leg color was associated with circulating carotenoids, but concentrations of these molecules were not related to antioxidant capacity, body condition or oxidative damage. These results indicate that carotenoid-based colorations may not be an honest signal of health status in this species. Production of carotenoid rich eggs coincided with low levels of circulating carotenoids in females, indicating that carotenoids might be a limited resource for laying female kestrels. Finally, young rearing males had higher levels of oxidative damage than females, and wild birds of both sexes had higher levels of these parameters than captive birds. These results may indicate that parental effort and physical activity are costly, independently from hormonal status. Since androgens did not explain carotenoid variation we suggest that multiple interacting factors can regulate carotenoid levels along the season.

Mitochondrial DNA variation of an isolated population of the Adriatic brook lamprey Lampetra zanandreai (Agnatha: Petromyzontidae): phylogeographic and phylogenetic inferences.

Two mitochondrial genes were examined to compare an isolated population of the Adriatic brook lamprey Lampetra zanandreai in central Italy with other populations in the species range (Po plain) and with parasitic and freshwater lampreys. A single haplotype, identical to one in a Venetian sample, was found in 10 individuals from the isolated population. The reduced variability is consistent with a history of dispersal after the Pleistocene expansion of the Po basin. The results support the hypothesis of an origin of L. zanandreai and L. fluviatilis-L. planeri from a common anadromous ancestor.

Chromosomal location and evolution of a satellite DNA family in seven sturgeon species.

The Hind III satellite DNA family, isolated from the Acipenser naccarii genome, was used as a probe for fluorescent in-situ hybridization (FISH) on the karyotype of seven sturgeon species, six belonging to the genus Acipenser and one to Huso. All species except one (A. sturio) exhibit from 8 to 80 chromosome hybridization signals, mainly localized at the pericentromeric regions. Eight chromosomes with weak hybridization signals are present in H. huso and A. ruthenus, which are characterized by a karyotype with about 120 chromosomes. The species with 240-260 chromosomes, A. transmontanus, A. naccarii, A. gueldenstaedtii, and A. baerii, show from 50 to 80 signals, prevalently localized around centromeres. Moreover, A. transmontanus and A. gueldenstaedtii show from 4 to 8 chromosomes with a double signal. The phylogenetic and evolutionary relationships among sturgeon species are discussed on the basis of number and morphology of signal-bearing chromosomes and on the localization of signals.

Sturgeon genetics and cytogenetics: recent advancements and perspectives.

The aim of this review is to introduce current knowledge in the field of sturgeon genetics. The first section deals with sturgeon cytogenetics, reviewing karyotype organization and polyploidization events during evolution of Acipenseriformes. The second section concerns the results of applications of molecular biology to studies of phylogenetic relationships between extant species, intraspecific analysis of wild populations and stocks for conservation purposes, together with characterization of molecular markers for species identification, relevant to forensic and conservation issues.

Maternal and paternal lineages in Albania and the genetic structure of Indo-European populations.

Mitochondrial DNA HV1 sequences and Y chromosome haplotypes (DYS19 STR and YAP) were characterised in an Albanian sample and compared with those of several other Indo-European populations from the European continent. No significant difference was observed between Albanians and most other Europeans, despite the fact that Albanians are clearly different from all other Indo-Europeans linguistically. We observe a general lack of genetic structure among Indo-European populations for both maternal and paternal polymorphisms, as well as low levels of correlation between linguistics and genetics, even though slightly more significant for the Y chromosome than for mtDNA. Altogether, our results show that the linguistic structure of continental Indo-European populations is not reflected in the variability of the mitochondrial and Y chromosome markers. This discrepancy could be due to very recent differentiation of Indo-European populations in Europe and/or substantial amounts of gene flow among these populations.

Major and 5S ribosomal sequences of the largemouth bass Micropterus salmoides (Perciformes, Centrarchidae) are localized in GC-rich regions of the genome.

Major and 5S ribosomal genes have been localized in the chromosomes of Micropterus salmoides. By C-banding, Ag-staining, CMA3-staining and 45S and 5S fluorescence in-situ hybridization (FISH), we demonstrate that the 45S and 5S ribosomal genes are clustered in two different chromosome pairs and both are located in heterochromatic GC-rich regions. PCR amplification and sequencing of the 5S intergenic non-transcribed sequences have allowed us to identify variability essentially due to a trinucleotide tandem repeat (GCT).

Molecular cytogenetic analysis of the karyotype of the European Atlantic sturgeon, Acipenser sturio.

A karyotype analysis was carried out on the European Atlantic sturgeon, Acipenser sturio (2n=121 +/- 3). The telomeric sequence repeat (TTAGGG)n detected by fluorescent in situ hybridization (FISH) was mostly localized at the telomeres of all chromosomes. Ribosomal DNA (rDNA) genes were detected by silver staining techniques and by FISH with digoxigenin-labelled probe for 28S rDNA. Silver staining detected active NORs in the telomeric regions of six chromosomes, and by FISH one or two additional minor sites were detected. The 5S rDNA was found in the interstitial region of a small metacentric pair. The 5S rRNA gene was completely sequenced for the first time in a sturgeon species. The A. sturio karyotype organization is discussed in relation to phylogenesis of the species within the Acipenseridae and to polyploidization events characterizing sturgeon evolution.

Polymorphic DdeI restriction sites in mitochondrial d-Loop DNA from Emilian blood donors.

We describe two new polymorphic sites identified by DdeI digestion of human mitochondrial D-Loop DNA. Their frequencies were estimated on a random group of 54 unrelated blood donors, born and descending from female ancestors of the Province of Reggio Emilia (Central Emilia, Northern Italy). These newly detected polymorphisms were generated by A to G transitions at positions 16300 and 16482 of mt-DNA. They were found at a 5% frequency in our sample whereas the remaining 95% of the sample exhibited a Cambridge sequence restriction pattern.

Oxidative cross-linking of fodrin parallels a membrane conductance increase in the mammalian lens.

An oxidative cross-linking of the lens spectrin-like protein fodrin was induced by incubating WKY-rat lenses in the presence of the SH-reagent diamide. The oxidation of fodrin was paralleled by an increase in lens membrane conductance. The time relationship between these two events as well as the reversibility of both, achieved by incubating the lens in the presence of dithiothreitol, indicate that normal permeability characteristics of the lens membranes require the integrity of the membrane attached cytoskeleton.

Cytoskeleton abnormalities in human senile cataract.

The cytoskeletal pattern of the most superficial layers (cortex and epithelium) of senile cataractous lenses has been analyzed by PAGE-SDS. While the nuclear type of cataract and age-matched transparent human lenses have superimposable protein patterns, lenses with cortical cataract demonstrate appreciable modifications of their cytoskeletal composition. The most evident change is the decrease of fodrin and the marked reduction or even the absence of the 98 Kd band. Fodrin may be completely removed from the water insoluble fraction (WIF) of cortical cataract by extraction in low ionic strength buffer, a treatment which only partially solubilizes this protein in transparent control lenses.

Carrier detection in Duchenne muscular dystropy.

We investigated the number of echinocytes, the serum hemopexin level, and spectrin band II phosphorylation in the blood of normal subjects, patients, and carriers of Duchenne dystrophy. The patients and carriers exhibited quantitatively significant differences with respect to controls.

Deformed erythrocytes in muscular dystrophies.

Because of previous reports of a possible correlation between echinocytogenesis and muscular dystrophies, we investigated the time-dependent development of echinocytes in the blood of normal subjects, patients, and healthy carries of Duchenne dystrophy. There was a quantitatively significant increase of echinocytes in patients and carriers.

[Erythrocyte changes (echino- and stomatocytic) in muscular dystrophy: research on possible applications in diagnosis and eugenics]. / "Il problema delle alterazioni eritrocitarie (echino e stomatocitiche) nella distrofia muscolare: ricerche sulle possibili applicazioni nella diagnostica e nell'eugenetica".

The Authors, after a brief review of the factors which influence the echino and stomatocytic erythrocyte's deformations and of the biochemical basis of these alterations, report the comparative study of the echino-stomatocytogenesis in both normal subjects and myodystrophic patients. In order to investigate whether this phenomenon is more developed in pathological condition, the results confirm that between normal subjects and myodystrophic patients or healthy carriers there is a quantitative significant difference which can be utilized for diagnostic and eugenic purposes. To obtain reliable results, the evaluation should be made at regular intervals of time from the blood drawing and after the exclusion of the presence of other disease or echino-stomatocytogenetic factors (drugs, etc.).

[Genetic observations on hereditary spherocytosis in some family groups in a region of Mantova north of the Po and/in the province of Parma]. / Osservazioni genetiche sulla sferocitosi ereditaria in alcuni gruppi familiari dell-Oltrepo Mantovano e della provincia di Parma

Hereditary spherocytosis is an haemolitic disease, generally characterized by anaemia, jaundice, and splenomegaly. With reference to data collected in the territory of Quistello, in the Province of Mantova and in the Hospital of the City of Parma, about 280 persons were examined, belonging to the families most affected by hereditary spherocytosis. The results support the hypothesis that the disease is due to an autosomic dominant gene with an almost complete penetrance (0.9). No significant decrease in fitness, measured as a function of fertility, was observed, nor was it possible, from the data examined, to evaluate any correlation between presence of the disease and cases of abortion or perinatal mortality. It is worthy of note that all the observed cases pertain to families that are distributed along the course of the Po River. A biochemical enquiry, based upon an evaluation of the differences in protein composition between the membranes of spherocytes and normal eritrocytes, by electrophoresis on gel of polyacrylamide, gave contrasting results.