Karyotypic and morphological divergence between two cryptic species of Eigenmannia in the Amazon basin with a new occurrence of XX/XY sex chromosomes (Gymnotiformes: Sternopygidae)

Espécies de Eigenmannia estão amplamente distribuídas na região Neotropical, com oito espécies válidas atualmente reconhecidas. Populações de Eigenmannia de três localidades do leste da Amazônia foram investigadas usando técnicas citogenéticas e morfológicas, revelando dois táxons designados aqui comoEigenmannia sp. "A" e Eigenmannia sp. "B". As espécies diferem em três caracteres morfométricos, dois merísticos e um osteológico. Eigenmannia sp. "A" apresenta 2n = 34 (22 m/sm+12st/a) e Eigenmannia sp. "B" apresenta 2n = 38 (14 m/sm+24st/a) e cromossomos sexuais de diferenciação simples, do tipo XX/XY. Em ambas espécies a Heterocromatina Constitutiva (HC) rica em bases A-T está distribuída na região centromérica de todos os cromossomos. Eigenmannia sp. "B" também apresenta blocos de HC na região intersticial dos pares cromossômicos 8, 9 e X que coraram positivamente para CMA₃, indicando regiões ricas em G-C. A NOR está localizada no braço curto do par 17 em Eigenmannia sp. "A" e no braço curto do par 14 em Eigenmannia sp. "B". FISH com sondas de rDNA hibridizaram em regiões de tamanhos diferentes entre os homólogos, sugerindo heteromorfismo. A diferenciação do cromossomo X em Eigenmannia sp. "B" pode ser o resultado de amplificação de sequências repetitivas de DNA.

Estimating cyclopoid copepod species richness and geographical distribution (Crustacea) across a large hydrographical basin: comparing between samples from water column (plankton) and macrophyte stands

Species richness and geographical distribution of Cyclopoida freshwater copepods were analyzed along the La Plata River basin. Ninety-six samples were taken from 24 sampling sites, twelve sites for zooplankton in open waters and twelve sites for zooplankton within macrophyte stands, including reservoirs and lotic stretches. There were, on average, three species per sample in the plankton compared to five per sample in macrophytes. Six species were exclusive to the plankton, 10 to macrophyte stands, and 17 were common to both. Only one species was found in similar proportions in plankton and macrophytes, while five species were widely found in plankton, and thirteen in macrophytes. The distinction between species from open water zooplankton and macrophytes was supported by nonmetric multidimensional analysis. There was no distinct pattern of endemicity within the basin, and double sampling contributes to this result. This lack of sub-regional faunal differentiation is in accordance with other studies that have shown that cyclopoids generally have wide geographical distribution in the Neotropics and that some species there are cosmopolitan. This contrasts with other freshwater copepods such as Calanoida and some Harpacticoida. We conclude that sampling plankton and macrophytes together provided a more accurate estimate of the richness and geographical distribution of these organisms than sampling in either one of those zones alone.

Development and characterization of microsatellite loci of microglanis cottoides (siluriformes: pseudopimelodidae) and cross-species amplification

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Isolation, Culture and Differentiation of Buffaloes Bone Marrow Mesenchymal Stem Cells Obtained from the Coxal Tuberosity

Currently, much attention has been devoted to the renewal of knowledge about Stem Cells and Cell Therapy in domestic species. In this sense, the present work aimed to develop a methodology for collecting, processing and cultivation of mesenchymal stem cells obtained from bone marrow of coxal tuberosity in buffaloes. The collection was performed using a Komiyashiki needle, which was introduced in the coxal tuberosity and the bone marrow aspirated into a heparinized syringe with the aid of negative pressure. Directly after collection samples were processed at the laboratory at FMVZ - UNESP. The samples took approximately 32 days to reach 80% confluence, when the first passage and differentiation was performed. To confirm the mesenchymal origin, cells were induced to differentiate into adipogenic and osteogenic lineages. Samples showed morphological changes during differentiation protocol, but not all presented production of extracellular deposits of calcium or intracellular fat droplets, observed after staining with Alizarin Red and Oil Red respectively. Compared with the material obtained from other species and processed in the same laboratory, the primary culture was longer. Therefore, more studies are needed to standardize the age of animals used and to test other inducers of cell differentiation.

Chromosomal Mapping of Repetitive DNA and Cytochrome C Oxidase I Sequence Analysis Reveal Differentiation among Sympatric Samples of Astyanax fasciatus (Characiformes, Characidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Population differentiation and speciation in the genus Characidium (Characiformes: Crenuchidae): effects of reproductive and chromosomal barriers

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Identification of species of the Euterpe genus by rare earth elements using inductively coupled plasma mass spectrometry and linear discriminant analysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Multiplex-PCR for differentiation of Mycobacterium bovis from Mycobacterium tuberculosis complex

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The community-level effect of light on germination timing in relation to seed mass: a source of regeneration niche differentiation

Within a community, species may germinate at different times so as to mitigate competition and to take advantage of different aspects of the seasonal environment (temporal niche differentiation). We illustrated a hypothesis of the combined effects of abiotic and biotic competitive factors on germination timing and the subsequent upscale effects on community assembly. We estimated the germination timing (GT) for 476 angiosperm species of the eastern Tibetan Plateau grasslands under two light treatments in the field: high (i.e. natural) light and low light. We also measured the shift in germination timing (SGT) across treatments for all species. Furthermore, we used phylogenetic comparative methods to test if GT and SGT were associated with seed mass, an important factor in competitive interactions. We found a significant positive correlation between GT and seed mass in both light treatments. Additionally, small seeds (early germinating seeds) tended to germinate later and large seeds (late germinating seeds) tended to germinate earlier under low light vs high light conditions. Low light availability can reduce temporal niche differentiation by increasing the overlap in germination time between small and large seeds. In turn, reduced temporal niche differentiation may increase competition in the process of community assembly.

Homomorphic Sex Chromosomes and the Intriguing Y Chromosome of Ctenomys Rodent Species (Rodentia, Ctenomyidae)

Unlike the X chromosome, the mammalian Y chromosome undergoes evolutionary decay resulting in small size. This sex chromosomal heteromorphism, observed in most species of the fossorial rodent Ctenomys, contrasts with the medium-sized, homomorphic acrocentric sex chromosomes of closely related C. maulinus and C. sp. To characterize the sequence composition of these chromosomes, fluorescent banding, self-genomic in situ hybridization, and fluorescent in situ hybridization with an X painting probe were performed on mitotic and meiotic plates. High molecular homology between the sex chromosomes was detected on mitotic material as well as on meiotic plates immunodetected with anti-SYCP3 and anti-gamma H2AX. The Y chromosome is euchromatic, poor in repetitive sequences and differs from the X by the loss of a block of pericentromeric chromatin. Inferred from the G-banding pattern, an inversion and the concomitant prevention of recombination in a large asynaptic region seems to be crucial for meiotic X chromosome inactivation. These peculiar findings together with the homomorphism of Ctenomys sex chromosomes are discussed in the light of the regular purge that counteracts Muller's ratchet and the probable mechanisms accounting for their origin and molecular homology. (C) 2014 S. Karger AG, Basel

MICROSATELLITE LOCI FOR ORTHOPHYTUM OPHIUROIDES (BROMELIOIDEAE, BROMELIACEAE) SPECIES ADAPTED TO NEOTROPICAL ROCK OUTCROPS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Paracrine and autocrine factors in the differentiation of the cumulus-oocyte complex

A better understanding of the paracrine and autocrine regulatory loops within the cumulus-oocyte complex (COC) is fundamental for the improvement of in vitro maturation (IVM) outcomes in humans and domestic species. This review presents the most important local regulators identified in the COC to date with special attention to those secreted by the oocyte and acting on cumulus cells, as well as their roles in different processes crucial for the successful maturation of the COC. An autocrine regulatory loop mediated by epidermal growth factor-like (EGF-like) peptides in cumulus cells triggers COC maturation. During COC differentiation, oocyte secreted factors (OSFs), particularly members of the transforming growth factor-beta (TGF beta) and fibroblast growth factor (FGF) families, regulate meiotic resumption, cumulus expansion, cumulus metabolism, apoptosis and steroidogenesis.

B chromosomes in the species Prochilodus argenteus (Characiformes, Prochilodontidae): morphologicalidentity and dispersion

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Differentiation of Haemonchus placei from Haemonchus contortus by PCR and by morphometrics of adult parasites and third stage larvae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molecular and cytogenetic analyses of cryptic species within the Synbranchus marmoratus Bloch, 1795 (Synbranchiformes: Synbranchidae) grouping: species delimitations, karyotypic evolution and intraspecific diversification

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)