Variabilidade genética de 12 loci de microssatélites em galinhas crioulas Canela-Preta / Genetic variability of twelve microsatellite loci in native Canela-Preta chickens

Esta pesquisa foi realizada com o objetivo de se conhecer a variabilidade genética de 12 loci de microssatélites em galinhas crioulas Canela-Preta. Foram coletadas amostras de sangue de 118 galinhas crioulas Canela-Preta, provenientes de três municípios do estado do Piauí (Oeiras, Queimada Nova e Teresina). Após extração do DNA, foram utilizados marcadores para 12 loci de microssatélites: LEI0192, LEI0209, LEI0212, LEI0217, LEI0221, LEI0234, LEI0237, LEI0248, LEI0258, MCW0081, MCW0183 e MCW0213, que foram amplificados pela técnica de reação em cadeia da polimerase (PCR). Foram obtidos 408 alelos (somando os alelos dos 12 loci), com os fragmentos variando entre 50 e 460 pares de bases. O número de alelos variou de 15 (MCW0081) a 52 (LEI0212), com média de 31,5 alelos por locus. A média de heterozigosidade esperada e o conteúdo de informações polimórficas foram, respectivamente, 0,887 e 0,909. Foram observados desvios no equilíbrio de Hardy-Weinberg e valores positivos do índice de fixação com excesso de homozigotos. Os microssatélites utilizados mostraram-se polimórficos e podem ser usados para investigações genéticas em galinhas Canela-Preta. As galinhas dos plantéis avaliados apresentam grande variabilidade gênica, o que as qualifica como importante fonte de recursos genéticos e, consequentemente, faculta a utilização delas em programas de melhoramento genético animal.(AU)

The aim of this study was to analyze the genetic variability of twelve microsatellite loci in native Canela-Preta chickens. Blood samples were collected from 118 chickens of the breed from five properties in three cities (Oeiras, Queimada Nova and Teresina) of Piauí state. After the DNA extraction, markers were used for twelve microsatellite loci: LEI0192, LEI0209, LEI0212, LEI0217, LEI0221, LEI0234, LEI0237, LEI0248, LEI0258, MCW0081, MCW0183, and MCW0213 that were amplified by polymerase chain reaction technique (PCR). The results showed a total of 408 alleles (adding alleles from the 12 loci) with the fragments ranging between 50 and 460 base pairs, the number of alleles ranged from 15 (MCW0081) to 52 (LEI0212) with an average of 31,5 alleles per locus. The average expected heterozygosity and PIC were, respectively, 0.887 and 0.909. Deviations were observed in the Hardy-Weinberg equilibrium and positive values of the fixation index with excess of homozygotes. It is concluded that the used microsatellites are polymorphic and can, therefore, be used for genetic research in Canela-Preta chickens. The birds of the analyzed cores present great genetic variability, which qualifies them as an important source of genetic resources, which could be used for future animal breeding programs.(AU)

Comparison of eight methods of genomic DNA extraction from babassu.

Babassu (Orbignya phalerata Martius) is one of the most important palms in Brazil because of the largest morphological variation, wide geographic distribution, and high socio-economic importance. The diversity present in babassu germplasm should be protected against loss to ensure their use with high productivity. Study of the available variability in populations of babassu is necessary to develop conservation strategies. The study of genetic variability can be conducted using molecular markers and many of these studies require significant quantity of high-quality DNA. The present study aimed to effect comparison among eight DNA extraction methods in case of O. phalerata. The quality and concentration of nucleic acids were analyzed by spectrophotometry and integrity of DNA was ascertained by agarose gel electrophoresis. The spectrophotometry revealed that some methods resulted in high levels of concentration of nucleic acids, in which values of the ratio A260/280 and A260/230 were outside the range of purity. The agarose gel electrophoresis established the concentration and integrity of DNA. The methods of Murray and Thompson (1980) and Ferreira and Grattapaglia (1998) did not result in satisfactory quantities of DNA. Conversely, the method proposed by Khanuja et al. (1999) resulted in DNA of adequate quality and quantity that could be satisfactorily used for amplification reactions performed with two ISSR primers.

Comparison of methods to isolate DNA from Caesalpinia ferrea.

Molecular markers are important for characterizing the genetic diversity of plants and can provide the basis for strategies to protect and conserve endangered populations. However, numerous molecular techniques are used, requiring an evaluation of fast and efficient methods to extract DNA. Since molecular studies of Caesalpinia ferrea are rare, it is important to develop and/or adapt a DNA extraction protocol that produces quality DNA samples to enable the design of strategies for the conservation of this threatened species. This study aimed to compare five methods for DNA extraction and to determine the most efficient protocol for C. ferrea. Sufficient genomic DNA was obtained from the leaves of C. ferrea using all the tested protocols to perform techniques involving molecular markers. Two protocols based on the detergent cetyl trimethyl ammonium bromide, as well as a commercial kit, yielded high concentrations of pure DNA. However, when polymerase chain reaction amplifications were performed, DNA was only successfully amplified from extractions performed with the commercial kit, which produced sufficient genomic DNA of good quality from the leaves of C. ferrea to perform techniques involving molecular markers.

RAPD analysis of the genetic diversity of mango (Mangifera indica) germplasm in Brazil.

We evaluated genetic variability of mango (Mangifera indica) accessions maintained in the Active Germplasm Bank of Embrapa Meio-Norte in Teresina, Piauí, Brazil, using RAPDs. Among these accessions, 35 originated from plantings in Brazil, six from the USA and one from India. Genomic DNA, extracted from leaf material using a commercial purification kit, was subjected to PCR with the primers A01, A09, G03, G10, N05, and M16. Fifty-five polymorphic loci were identified, with mean of 9.16 ± 3.31 bands per primer and 100% polymorphism. Application of unweighted pair group method using arithmetic average cluster analysis demonstrated five genotypic groups among the accessions examined. The genotypes Rosa 41, Rosa 48 and Rosa 49 were highly similar (94% similarity), whereas genotypes Sensation and Rosa 18 were the most divergent (only 7% similarity). The mango accessions were found to have considerable genetic variability, demonstrating the importance of analyzing each genotype in a collection in order to efficiently maintain the germplasm collection.

Single primer-based DNA amplification as a suitable and low-cost tool for assessing genetic diversity in mangrove crabs.

We used single primer-based DNA markers to assess genetic variability of the mangrove crab, Ucides cordatus, collected from four different localities from Pará to Santa Catarina States in Brazil (almost 5000 km distant). Five primers were chosen based on the consistency of the amplified bands and the polymorphism of each locus. A total of 78 loci were amplified in 76 samples; high polymorphism rates were detected in the entire sample (80.8%) and within each locality (73.5-79.5%). Analysis of molecular variance demonstrates significant differences between localities (P < 0.001); however, the Φ(ST) value (0.078) indicates a low level of genetic differentiation, which suggests that U. cordatus larvae can spread over large distances. The variation was distributed among the samples, and most of it was attributed to differences among individuals within localities. Cluster analysis, based on the Jaccard similarity coefficient, and the Mantel test gave similar results to the analysis of molecular variance data. Despite the low level of population structuring, these markers could be used for studying U. cordatus diversity, due to the high level of polymorphism.

Histology and histochemistry of the ventriculus of Dolichoderus (=Monacis) bispinosus (OLIVIER, 1792) (Hymenoptera: Formicidae).

In this study we histologically and histochemically describe the ventriculus of Dolichoderus bispinosus. The epithelium consists of two basic cell types, highly basophilic generative cells, and digestive cells. The latter present several cytoplasmic vesicles, rich in acidic and neutral polysaccharides, and basic proteins. Also, these cells exhibit an apocrine secretion pattern. A mass of fibrous material is observed on the surface of the epithelium. Finally, we discuss the results obtained.

Ultramorphological analysis of the venom glands and their histochemical relationship with the convoluted glands in the primitive social paper wasp Polistes versicolor (Hymenoptera: vespiade)

The venom glands are part of the most important defense weapon in Aculeata: the venom apparatus. The arrangement of these glands can vary among species, but in general they are composed of long secretory tubules connected to a muscular sac-like reservoir. Although the occurrence of these variations has been documented, many studies neglected the existence of a well-developed secretory portion in the lumen of the reservoir named convoluted gland. This study is an ultramorphological analysis of the venom glands and their histochemical relationship with the convoluted glands in the primitive social wasp Polistes versicolor. In this wasp, the venom glands are constituted by two tubular portions tha penetrate individually in the venom reservoir, inside of which we can find the convoluted glands. Besides morphological differences in their cells, histochemical analysis of the venom and convoluted glands clearly show differences between them. While the venom glands indicate positive reaction only for proteins, the convoluted glands present positive reaction for proteins, neutral glycoconjugates, and lipids. The secretion of the convoluted gland cells may modify the compounds passing through the embedded tubular region