Asunto(s)
Composición Corporal , Proteínas Portadoras/genética , Bovinos/fisiología , Carne/análisis , Polimorfismo de Nucleótido Simple , Animales , Proteínas Portadoras/metabolismo , Bovinos/genética , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN/veterinariaRESUMEN
BACKGROUND: Marbling defined by the amount and distribution of intramuscular fat, so-called Shimofuri, is an economically important trait of beef cattle in Japan. Our previous study detected 3 single nucleotide polymorphisms (SNPs), g.231054C > T, g.3109537C > T and c.*188G > A, respectively, in the 5' flanking region of the titin (TTN), the 5' flanking region of the ribosomal protein L27a (RPL27A) and the 3' untranslated region of the akirin 2 genes (AKIRIN2), which have been considered as positional functional candidates for the genes responsible for marbling, and showed association of these SNPs with marbling in Japanese Black beef cattle. In the present study, we investigated the allele frequency distribution of the 3 SNPs among the 5 cattle breeds, Japanese Black, Japanese Brown, Japanese Shorthorn, Holstein and Brown Swiss breeds. FINDINGS: We genotyped the TTN g.231054C > T, RPL27A g.3109537C > T and AKIRIN2 c.*188G > A SNPs by polymerase chain reaction-restriction fragment length polymorphism method, using 101 sires and 1,705 paternal half sib progeny steers from 8 sires for Japanese Black, 86 sires and 27 paternal half sib progeny steers from 3 sires for Japanese Brown, 79 sires and 264 paternal half sib progeny steers from 14 sires for Japanese Shorthorn, 119 unrelated cows for Holstein, and 118 unrelated cows for Brown Swiss breeds. As compared to the frequencies of the g.231054C > T T, g.3109537C > T T and c.*188G > A A alleles, associated with high marbling, in Japanese Black breed that has been subjected to a strong selection for high marbling, those in the breeds, Japanese Shorthorn, Holstein and Brown Swiss breeds, that have not been selected for high marbling were null or lower. The Japanese Brown breed selected slightly for high marbling showed lower frequency than Japanese Black breed in the g.3109537C > T T allele, whereas no differences were detected between the 2 breeds in the frequencies of the g.231054C > T T and c.*188G > A A alleles. CONCLUSIONS: Based on this finding, we hypothesized that the pressure of the strong selection for high marbling in Japanese Black breed has increased the frequencies of the T, T and A alleles at the TTN g.231054C > T, RPL27A g.3109537C > T and AKIRIN2 c.*188G > A SNPs, respectively. This study, together with the previous association studies, suggested that the 3 SNPs may be useful for effective marker-assisted selection to increase the levels of marbling.
RESUMEN
Our previous study detected 291 and 77 genes showing early embryonic death-associated elevation and reduction of expression, respectively, in the fetal placenta of the cow carrying somatic nuclear transfer-derived cloned embryo. In this study, we mapped the 10 genes showing the elevation and the 10 genes doing the reduction most significantly, using somatic cell hybrid and bovine draft genome sequence. We then compared the mapped positions for these genes with the genomic locations of bovine quantitative trait loci for still-birth and/or abortion. Among the mapped genes, peptidylglycine alpha-amidating monooxygenase (PAM), spectrin, beta, nonerythrocytic 1 (SPTBNI), and an unknown novel gene containing AU277832 expressed sequence tag were intriguing, in that the mapped positions were consistent with the genomic locations of bovine still-birth and/or abortion quantitative trait loci, and thus identified as positional candidates for bovine placental genes responsible for the early embryonic death during the pregnancy attempted by somatic nuclear transfer-derived cloning.
Asunto(s)
Clonación de Organismos/veterinaria , Pérdida del Embrión/veterinaria , Placenta/metabolismo , Preñez/genética , Animales , Bovinos , Mapeo Cromosómico , Pérdida del Embrión/genética , Etiquetas de Secuencia Expresada , Femenino , Expresión Génica , Oxigenasas de Función Mixta/genética , Complejos Multienzimáticos/genética , Técnicas de Transferencia Nuclear/veterinaria , Embarazo , Sitios de Carácter Cuantitativo , Espectrina/genéticaRESUMEN
A quantitative trait locus (QTL) responsible for intramuscular fat accumulation in Musculus longissimus of Otsuka Long-Evans Tokushima Fatty (OLETF) rat, Imfm, was previously mapped to the approximately 10-cM genomic region between D1Rat166 and D1Rat90 on chromosome 1 using Imfm congenic strain. In this study, we refined the Imfm region to a approximately 2.3-cM genomic region between D1Rat225 and D1Rat90, using 12 informative recombinants selected from 176 (Imfm congenic x F344) F, x Imfm congenic backcross progenies. Among 46 genes located within the approximately 2.3-cM region, pancreatic lipase gene, Pnlip, that is a possible candidate for obesity QTL, Nidd6/of, was thought to be the most prominent and physiologically relevant positional candidate for the Imfm QTL. It was previously showed that Pnlip possesses an OLETF allele-specific increase of mRNA levels in the pancreas, and that the OLETF allele is longer in variable number of tandem repeat (VNTR) within the 5'-flanking region than normal alleles. We found complete cosegregation of the Imfm QTL with Pnlip VNTR in the 12 informative recombinants, suggesting that Pnlip is also a possible candidate for the Imfm QTL.
Asunto(s)
Adiposidad/genética , Lipasa/genética , Músculo Esquelético/anatomía & histología , Ratas Endogámicas OLETF/anatomía & histología , Ratas Endogámicas OLETF/genética , Animales , Animales Congénicos , Femenino , Endogamia , Masculino , Músculo Esquelético/enzimología , Sitios de Carácter Cuantitativo , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas OLETF/metabolismoRESUMEN
We have recently showed that the 7 expressed sequence tags (ESTs), c2-11#2, c3-3, c20-29, c22-3, c26-18#1, c26-42, and g5-10, possess expression differences in musculus longissimus muscle between low-marbled and high-marbled steer groups. In the present study, we detected single nucleotide polymorphisms (SNPs) in the 5' flanking regions of the 7 EST sequences between the 2 steer groups. A SNP for the c2-11#2 EST exhibited significantly different allelic distribution between animals with extremely high predicted breeding value for marbling and with extremely low one. The SNP in the ribosomal protein L27a (RPL27A) gene containing the c2-11#2 EST sequence may be related to changes in gene expression and/or marbling.
Asunto(s)
Distribución de la Grasa Corporal/veterinaria , Bovinos/anatomía & histología , Bovinos/genética , Etiquetas de Secuencia Expresada , Polimorfismo Genético , Tejido Adiposo/anatomía & histología , Alelos , Animales , Cruzamiento , Expresión Génica , Masculino , Músculo Esquelético/anatomía & histología , Polimorfismo de Nucleótido SimpleRESUMEN
We have recently showed that the pyruvate dehydrogenase (lipoamide) beta (PDHB) gene involved in fatty acid oxidation, the sorbin and SH3 domain containing 1 (SORBS1) gene involved in insulin-stimulated glucose uptake, and the endothelial differentiation, sphingolipid G-protein-coupled receptor, 1 (EDG1) gene involved in blood vessel formation possess expression differences in musculus longissimus muscle between low-marbled and high-marbled steer groups. In the present study, we detected single nucleotide polymorphisms (SNPs) in the promoter regions of the 3 genes between the 2 steer groups. A SNP in the EDG1 exhibited significantly different allelic distribution between animals with extremely high predicted breeding value for marbling and with extremely low one. The EDG1 SNP may be related to changes in gene expression and/or marbling.
Asunto(s)
Distribución de la Grasa Corporal/veterinaria , Bovinos/anatomía & histología , Bovinos/genética , Proteínas de Microfilamentos/genética , Piruvato Deshidrogenasa (Lipoamida)/genética , Receptores de Lisoesfingolípidos/genética , Tejido Adiposo/anatomía & histología , Alelos , Animales , Cruzamiento , Masculino , Músculo Esquelético/anatomía & histología , Polimorfismo de Nucleótido Simple , Regiones Promotoras GenéticasRESUMEN
The Otsuka Long-Evans Tokushima Fatty (OLETF) rat exhibits polygenic obesity, and one of quantitative trait loci (QTLs) responsible for a susceptibility to obesity in the OLETF, Nidd6/of, has been mapped to the approximately 10-cM genomic region between D1Rat166 and D1Rat90 on chromosome 1 in (OLETF x normal) F2 intercross. In this study, we have attempted to identify the causal gene for the Nidd6/of QTL. A Nidd6/of congenic strain, constructed by introgressing the OLETF allele on the mapped Nidd6/of region in the normal F344 rat strain, confirmed the existence of the Nidd6/of as obesity QTL. The Nidd6/of region was refined to a approximately 2.3-cM genomic region between D1Rat225 and D1Rat90, using informative recombinants selected from (Nidd6/of congenic x F344) F1 x Nidd6/of congenic backcross progenies. Among 46 genes located within the approximately 2.3-cM region, pancreatic lipase gene, Pnlip, was regarded as the most prominent and physiologically relevant positional candidate for the Nidd6/of QTL. We found that Pnlip possesses an OLETF allele-specific increase of mRNA levels in the pancreas, and that the OLETF allele is longer in variable number of tandem repeat (VNTR) within the 5'-flanking region than normal alleles. We further showed that the Nidd6/of QTL completely cosegregates with Pnlip VNTR in the informative recombinants from (Nidd6/of congenic x F344) F1 x Nidd6/of congenic backcross progenies. These results suggest that Pnlip is possible candidate for the Nidd6/of QTL.
Asunto(s)
Lipasa/genética , Obesidad/genética , Páncreas/enzimología , Sitios de Carácter Cuantitativo , Animales , Secuencia de Bases , Cartilla de ADN , Repeticiones de Minisatélite , Obesidad/enzimología , Polimorfismo Genético , ARN Mensajero/genética , ARN Mensajero/metabolismo , RatasRESUMEN
The rat strain Otsuka Long-Evans Tokushima Fatty (OLETF) is an animal model for type 2 diabetes mellitus. Nidd8/of has been identified as one of 14 quantitative trait loci (QTLs) involved in the diabetes by a whole genome search in 160 F2 progenies obtained by mating the OLETF and F344 rats. Comparative mapping between human and rat indicated that the Nidd8/of genomic region, near D9rat21 on rat chromosome 9, contains the calpain10 (Capn10) gene, which is putative type 2 diabetes-susceptibility gene in humans. In this study, we found no difference in Capn10 mRNA expression in the heart, liver, skeletal muscle and pancreas between OLETF and F344 rats at 5 and 10 weeks of age. However, we found a single nucleotide polymorphism (SNP) (A/A genotype in OLETF and G/G genotype in F344 and LETO rats) at the base 583 downstream from the translation start site in the rat Capn10 cDNA sequence. This SNP was deduced to substitute serine (OLETF) for glycine (F344 and LETO) at the 195 amino acid residue within the protease domain of rat Capn10. Because serine is generally not interchangeable with glycine in respect of the protein structure and function, it was deduced that the A/A genotype in OLETF is not a 'safe' mutation. This non-conservative amino acid substitution might be associated with susceptibility to type 2 diabetes in OLETF rats.
Asunto(s)
Calpaína/genética , Diabetes Mellitus Tipo 2/genética , Animales , Calpaína/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Mutación , Especificidad de Órganos , Ratas , Ratas Endogámicas OLETFRESUMEN
A genomic region between D1Wox8 and D1Rat90 on rat chromosome 1 was previously shown to be linked to intramuscular fat accumulation by quantitative trait locus (QTL) analysis using a F2 population derived from the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, which exhibits an increase in the levels of intramuscular fat content in Musculus longissimus, and the F344 rat. There exist two regions showing major and minor lod peaks for linkage to intramuscular fat accumulation, in the chromosomal region. We constructed a congenic strain introgressing the OLETF allele on the minor but not the major lod peak region in the F344 rat strain. The congenic strain had higher levels of intramuscular fat content in Musculus longissimus than the inbred partner F344 rat, thereby proving the existence of a QTL, designated Imfm (for Intramuscular fat-minor), responsible for the intramuscular fat accumulation in the congenic region of the minor lod peak region of about 10 cM. The F344.OLETF-Imfm congenic strain might provide a refined tool for the analysis of the gene causing intramuscular fat accumulation.