Níveis de expressão dos genes FABP3 e FABP4 e conteúdo de gordura intramuscular em suínos

• Autor(a) principal: Moraes, Danielle Serra de Lima
• Data de Publicação: 2006
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1294
• topic: Suíno; Genética molecular; Gordura intramuscular; Pigs; Molecular genetics; Intramuscular fat; CNPQ::CIENCIAS BIOLOGICAS::GENETICA::GENETICA ANIMAL

Genes FABP3 (heart fatty acid-binding protein gene) and FABP4 (adipocyte fatty acid-binding protein gene) have been indicated as candidate genes to the intramuscular fat deposition in pigs. The present research aimed to analyze the levels of expression of these genes in the Longissimus dorsi (LD) and Semimembranosus (SM) muscles of commercial (Landrace X Large White X Pietrain) and Brazilian native (Piau breed) pigs (gilts and barrows) at different ages. It also aimed to evaluate the correlation between these expression levels and intramuscular fat content. Eighteen samples of the two divergent genetic groups of pigs were slaughtered. Of these 12 were samples of commercial pigs at the ages of 1, 21, 60, 90, 120 and 180 days and 6 were of Brazilian native pigs (Piau) at the ages of 1, 90 and 180 days. Samples of the LD and SM muscles of these animals were removed immediately after slaughter. They were frozen in liquid nitrogen at -70 ºC. The analyses for intramuscular fat content were conducted in pools of equivalent samples (tissues of pigs of the same sex, age and genetic group). The RNA of the samples was extracted and the genes FABP3 anda FABP4 expressions were analysed from Real Time PCR, using the TaqmanTM technology. In the present research were use the relative quantification type (comparative method). The results of the genes FABP3 and FABP4 expression and of the intramuscular fat content were submitted to statistical analyses, using a model containing the effects of the genetic group, sex and animal age. There was no significant genetic group and sex effects for the expression levels of both FABP3 and FABP4 genes. Significant age effect was verified at the levels of 1 and 5%, respectively, for the expression of both FABP3 and FABP4 genes in commercial pigs. Average expression obtained at birth differed significantly from the other ages. There was significant effect of sex and age on the intramuscular fat content of commercial pigs LD muscle. Significant correlation between FABP3 and FABP4 genes was found in both of the genetic groups. No significant correlations were obtained between these genes and intramuscular fat content. These results suggest that: 1) the period immediately after birth was important in the expression of genes FABP3 and FABP4 in both populations; 2) FABP3 and FABP4 genes did not present potential to be used as molecular markers for intramuscular fat deposition in the populations evaluated, but they might be used as predictors of adaptations and/or metabolic alterations of the LD and SM muscles.