ABSTRACT The objective of this study was to evaluate the association of polymorphisms in the diacylglycerol acyltransferase ( DGAT ) and leptin ( LEP ) genes with the performance, carcass characteristics, meat quality, and lipid profile of Nellore cattle. A total of 100 intact male Nelore cattle were used to analyze the performance, carcass, physicochemical and centesimal composition, and fatty acid profile of beef. To identify the polymorphisms, the PCR–single-strand conformation polymorphism (SSCP) technique was applied to genomic DNA extracted from muscle tissue. The SSCP technique revealed the presence of four band patterns for the DGAT gene (AC, AD, AE and BB) with five alleles (A, B, C, D and E). For the LEP gene, five band patterns (AA, AB, AC, BB and BC) with three alleles (A, B and C) were observed. For the LEP gene, the AB genotype was associated with higher backfat thickness and ribs weight, while the BB genotype was associated with lower ribs yield; higher hindquarter yield was associated with AC and BB genotypes. Higher contents of C17:0, C18:0 and lower contents of C18:2ω6C, total polyunsaturated fatty acids, total ω6 and ratio of polyunsaturated and saturated fatty acids (PUFA/SFA) were verified for the AC genotype of the LEP gene. The AC and AA genotypes of the LEP gene were associated with higher means of C15:0 and C18:1ω9t. For the DGAT gene, the highest C24:0 content was associated with the AE genotype and the lowest with the AD and BB genotypes. Polymorphisms in the DGAT and LEP genes influence carcass parameters and the lipid profile of the meat of Nellore cattle.

RESUMO Objetivou-se com este estudo avaliar a associação do polimorfismo dos genes da Diacilglicerol Aciltransferase ( DGAT) e Leptina – (L EP ) em relação ao desempenho, características de carcaça, qualidade de carne e perfil lipídico de bovinos Nelore. Para o estudo, foram utilizados um total de 100 bovinos nelores machos inteiros e avaliado os parâmetros de desempenho, composição da carcaça, composição físico-química, centesimal e perfil lipídico da carne. Para identificação dos polimorfismos foi utilizada a técnica de PCR-SSCP a partir da extração do DNA genômico do tecido muscular. A técnica de SSCP revelou a presença de quatro padrões de banda para o gene DGAT (AC, AD, AE e BB) com cinco alelos (A, B, C, D e E) e, para o gene LEP foram verificados cinco padrões de bandas (AA, AB, AC, BB e BC) com três alelos (A, B e C). Para o gene LEP, o genótipo AB foi associado a maior espessura de gordura subcutânea e peso do corte ponta de agulha, enquanto o genótipo BB foi associado a menor rendimento do corte ponta de agulha; maior rendimento do corte traseiro foi associado aos genótipos AC e BB. Maiores teores de C17:0, C18:0 e menores de C18: 2ω6C, total de ácidos graxos poli-insaturados, total de ω6 e a relação de ácidos graxos poli-insaturados e saturados (POL/SAT) foram verificados para o genótipo AC do gene LEP. Os genótipos AC e AA do gene LEP foram associados a maiores médias de C15:0 e C18:1ω9t. Para o gene DGAT, os maiores teores de C24:0 foram associados o genótipo AE e o menores aos genótipos AD e BB. A ocorrência de polimorfismo nos genes DGAT e LEP revelaram influência destes sobre parâmetros de carcaça e perfil lipídico da carne de bovinos Nelore.

ABSTRACT. The study of promoters has become essential to elucidate genetic regulation and allow new genetic transformation strategies through plant biotechnology. The challenge is to discover and validate promoters that can regulate gene transcription spatially and/or temporally. The goal of this work was to validate genes associated with tissue-specific promoters of bananas obtained from in silico sequences and selected from the DATAMusa databank. Gene expression was quantified using RT-qPCR from different tissues: leaves, flowers, roots, unripe pulp, ripe pulp, unripe peels, and ripe peels of two different genetic groups: Prata-Anã (PA; group AAB) and Grand Naine (GN; group AAA). After the analysis of the expression of genes associated with the promoters, normalization was performed with the most stable reference genes (TUB and L2) selected using the RefFinder tool. It was determined that five genes were specific or expressed to a greater extent in some tissues than others. The EMB-23 gene was highly expressed in ripe pulp and flowers of GN, EMB-26 in the ripe pulp of GN, EMB-27 in flowers of GN, EMB-28 in roots of PA and ripe pulp and roots of GN, and EMB-31 in roots and flowers of GN and PA, and unripe pulp of GN. The in silico analysis was efficient in the identification of spatial/time-specific genes, thereby decreasing analysis time and cost, making future genetic transformation studies focusing on the application of these tissue-specific promoters possible.

RESUMO A dieta básica de grande parte da população mundial é provida pelos cereais que, geralmente, apresentam teores de ferro (Fe) e zinco (Zn) aquém da demanda nutricional do homem. Outros fatores que podem contribuir, substancialmente, para a baixa ingestão de Fe e Zn são os fatores antinutricionais, presentes nas partes comestíveis das plantas, como os metais pesados e o fitato. Por essas razões, objetivou-se, com este trabalho, avaliar a variação genotípica quanto à produtividade de grãos (kg ha-1), à altura de plantas e à de inserção de primeira vagem, bem como aos teores de Fe, de Zn, de fósforo (P) e do antinutriente fitato nos grãos, de 24 cultivares de soja, além de detectar cultivares com potencial para biofortificação. O experimento de campo foi conduzido em Rio Verde, Goiás, pelo Centro Tecnológico da COMIGO. O delineamento experimental utilizado foi o de blocos ao acaso, com 24 tratamentos e três repetições. Os resultados mostraram que há variação genotípica para produtividade de grãos (kg ha-1), para alturas de plantas e de inserção de primeira vagem, bem como para os teores de Fe, Zn, P e do antinutriente fitato, nos grãos, entre os cultivares de soja. Verificaram-se correlações baixas ou não significativas entre as variáveis avaliadas, exceto para a relação entre P e fitato (r = 0,733). A diversidade encontrada entre os cultivares de soja oferece genótipos, como AS 8197RR, M 7908RR e FMS BRS 262, com potencial para desenvolver cultivares com maiores habilidades de acumular nutrientes em grãos.

ABSTRACT The staple diet of most of the world population is provided by cereal, which present levels of iron (Fe) and zinc (Zn) below the nutritional demand of humans. Other factors that may substantially interfere for the low intake of Fe and Zn are the anti- nutritional factors present in the edible parts of plants, such as heavy metals and phytate. Hence, the objective of this study was to evaluate the genotypic variation in terms of yield (kg ha-1), plant height, insertion height of first pod, as well as concentrations of Fe, Zn, phosphorus (P) and the anti-nutrient phytate in grains of 24 soybean cultivars and to identify cultivars with potential for biofortification. The field experiment was conducted in Rio Verde, state of Goiás by the technological center of COMIGO. The experimental design used in the study was a randomized block design with 24 treatments and three replications. The results showed that there is genotypic variation for grain yield (kg ha-1), plant height, and insertion height of first pod, as well as for the concentrations of Zn, Fe, P and concentration of anti-nutient phytate in grains among the soybean cultivars. Non-significant or low correlations were found among the evaluated parameters except for the relationship between P and phytate (r=0.733). The diversity found among soybean cultivars offers genotypes such as 8197RR, M 7908RR and BRS 262 with potential to develop cultivars with better ability to accumulate nutrients in grains.

O objetivo deste trabalho foi caracterizar e comparar dois tipos de calos de explantes foliares de Coffea arabica (cultivar Catiguá). Células de diferentes tipos de calos foram caracterizadas quanto a viabilidade e características morfológicas externas e internas. Foram obtidos dois tipos de calos morfologicamente distintos: (a) amarelo friável e (b) transparente aquoso. Os calos amarelos friáveis apresentaram maior viabilidade celular e características embriogênicas. Microscopia eletrônica de varredura e transmissão mostraram características embriogênicas em calos amarelos friáveis evidenciadas pela presença de células pequenas e isodiamétricas. Os calos transparentes aquosos apresentaram células alongadas e vacuolizadas.

The aim of this research was to characterize and compare two types of calli from leaf explants of Coffea arabica (cultivar Catiguá). Cells of different types of callus were successfully characterized regarding viability and internal and external morphological characteristics. It was obtained two morphologically distinct types of callus: (i) yellow friable and (ii) transparent watery. The yellow friable calli showed higher cell viability and embryogenic characteristics. Scanning and transmission electron microscopy showed embryogenic characteristics in cells of the yellow friable calli evidenced by the presence of small and isodiametric cells, while transparent watery calli showed elongated cells and large cytoplasm vacuolization.