Genetic analyses allowed management and conservative programmes specifically designed for biodiversity conservation purposes. To date, no information is available for the
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e definition of any ...Italian northern pike population, because of their wide, highly fragmented, distribution. Low gene flow levels may have caused some of the health population problems emerging from professional fisheries data, underlining a marked reduction of these populations. This paper reports the first estimate of genetic
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e of the Lake Trasimeno's northern pike, by means of microsatellites data, over the last four decades compared with five other significant Italian populations.
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e values were evaluated through specific software and
θ estimator. The
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e results confirm that, despite a marked reduction between 1966 and 1997 and a less than optimal status, the Trasimeno population shows a positive trend in its health status, presumably due to proper management programmes. Considerations on the biological conservation and management of this pike population are also reported.
The Etruscan chub Squalius lucumonis (Bianco, 1983) is an endemic endangered fish inhabiting the lakes and rivers of Central Italy. A microsatellite-enriched genomic library was constructed in order ...to develop microsatellite loci and eight polymorphic loci were isolated from this species to assess the level of genetic diversity in fifty individuals of S. lucumonis collected in the Umbria Region. The number of alleles ranged from four (Sluc12) to 18 (Sluc4). Observed and expected heterozygosity per locus ranged from 0.05 (Sluc12) to 0.80 (Sluc4; Sluc7 and Sluc11) and from 0.22 (Sluc12) to 0.90 (Sluc4), respectively. Furthermore, these loci were tested on ten other Cyprinidae species and four freshwater fish species belonging to other families. Successful cross-priming amplifications were obtained for several species of Cyprinidae, whereas no positive results were obtained for other species. The availability of the reported microsatellite loci will facilitate population structure investigations of these species aiming to phylogeographical approaches and conservation strategies.
The two freshwater sponges Ephydatia fluviatilis and Ephydatia mülleri belong to the widespread Spongillidae family. Their morphological tracts are very similar and can be distinguished mainly on the ...basis of their gemmuloscleres. However, when gemmules are absent it is essential to have an unambiguous species attribution for a population genetic study based on fresh tissues and historical collections. This article reports a simple Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) analysis, applied to DNA extracted from both gemmules and fresh tissues in order to discriminate between the two congeneric E. fluviatilis and E. mülleri. Such a biomolecular method is based on the discriminative enzymes' digestion of each of the three amplified fragments 5.8S-ITS2-28S, D3 domain of the 28S subunit and COI. Two restriction enzymes were tested for a 620-642 bp fragment of 5.8S-ITS2-28S and for a 342 bp fragment of the D3 domain of the 28S, one restriction enzyme was tested for a 681 bp fragment codifying for COI. Obtained digestion patterns were diagnostic for each of the two species, providing a relatively simple, fast and cheap method for species attribution compared to sequencing.
The expansins comprise a family of proteins that appear to be involved in the disruption of the noncovalent bonds between cellulose microfibrils and cross-linking glycans, thereby promoting wall ...creep. To understand better the expansion process in Petunia hybrida (petunia) flowers, we isolated a cDNA corresponding to the PhEXP1 -expansin gene of P. hybrida. Evaluation of the tissue specificity and temporal expression pattern demonstrated that PhEXP1 is preferentially expressed in petal limbs during development. To determine the function of PhEXP1, we used a transgenic antisense approach, which was found to cause a decrease in petal limb size, a reduction in the epidermal cell area, and alterations in cell wall morphology and composition. The diminished cell wall thickness accompanied by a reduction in crystalline cellulose indicates that the activity of PhEXP1 is associated with cellulose metabolism. Our results suggest that expansins play a role in the assembly of the cell wall by affecting either cellulose synthesis or deposition.
The two freshwater sponges Ephydatia fluviatilis and Ephydatia muelleri belong to the widespread Spongillidae family. Their morphological tracts are very similar and can be distinguished mainly on ...the basis of their gemmuloscleres. However, when gemmules are absent it is essential to have an unambiguous species attribution for a population genetic study based on fresh tissues and historical collections. This article reports a simple Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) analysis, applied to DNA extracted from both gemmules and fresh tissues in order to discriminate between the two congeneric E. fluviatilis and E. muelleri. Such a biomolecular method is based on the discriminative enzymes' digestion of each of the three amplified fragments 5.8S-ITS2-28S, D3 domain of the 28S subunit and COI. Two restriction enzymes were tested for a 620-642 bp fragment of 5.8S-ITS2-28S and for a 342 bp fragment of the D3 domain of the 28S, one restriction enzyme was tested for a 681 bp fragment codifying for COI. Obtained digestion patterns were diagnostic for each of the two species, providing a relatively simple, fast and cheap method for species attribution compared to sequencing.
Three chlorate-resistant mutants of the cyanobacterium Spirulina platensis were obtained by UV irradiation and one of them (LL1) was further characterized for its nutritional requirements and for the ...capacity to reduce nitrate in vivo and in vitro. The results indicate that mutation leading to chlorate resistance is not due to inactivation of nitrate reductase but is most likely due to the loss of permeability to chlorate and nitrate. The other two mutants seem to have properties similar to those of LL1.
A cyclin cDNA clone (
Pethy;CycB1;1) was isolated from a
Petunia hybrida ovary specific cDNA library. Sequence comparison revealed that Pethy;CYCB1;1 protein is highly homologous to mitotic B1 ...cyclins. Northern analysis and in situ hybridisation experiments showed that its expression is developmentally regulated and restricted to flower organs. We have attempted to define some of the cell division patterns which contribute to shaping each floral organ by analysing
Pethy;CycB1;1 expression on
Petunia flower sections. While in sepals, epidermis and parenchyma cell division patterns were comparable, there were two distinct cell division patterns in petals. In the epidermis,
Pethy;CYCB1;1 expression was found both at the petal tip and along epidermis, whereas in the parenchyma only at the petal tips. In reproductive organs cell divisions were detected only in sporophytic tissues. No signals were detected inside meiotic cells.
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