RESUMEN
3-hydroxy-3-methylglutaryl-Coenzyme A reductase (HMGR) is the rate-limiting enzyme for cholesterol synthesis. Its activity is regulated via a negative feedback mechanism through sterols and non-sterol metabolites derived from mevalonate, the product of the reaction catalyzed by reductase. Here, we cloned a full-length transcript of porcine HMGR by RT-PCR and RACE. The porcine HMGR cDNA (2864 bp,GenBank accession no. DQ432054) contains a 2658 bp open reading frame and shares 91% identify with those of human and cattle, and 85%, 85% and 84% identify with the HMGR coding sequences of Norway rat, golden hamster, and house mouse, respectively. The deduced porcine HMGR protein consists of 885 amino acids with a calculated molecular mass of 97.15 kDa(GenBank accession no. ABD96089). The amino acid sequence similarities correspond to 95%, 95%, 92%, 92% and 92% when compared with human, cattle, Norway rat, golden hamster and house mouse sequences, respectively. The structure and function of HMGR deduced protein product were predicted by bioinformatic approaches. HMGR-specific transcripts were found in 15 different tissues from pig by RT-PCR and Real-time PCR. The relative expression level of HMGR was high in liver, heart, kidney, bladder and subcutaneous fat, medium in lung, uterus and large intestine, and low in cerebrum, spleen, spinal cord, stomach, ovary, longissimus muscle, and small intestine. The SNPs analysis of HMGR showed that there were five SNPS and three of them are synonymous mutations and the other two are missense mutations. Taken together, our data may lay a ground for further investigation of HMGR's functions and regulatory mechanisms in swine.
Asunto(s)
Hidroximetilglutaril-CoA-Reductasas NADP-Dependientes/genética , Hidroximetilglutaril-CoA-Reductasas NADP-Dependientes/metabolismo , Porcinos/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , Femenino , Regulación Enzimológica de la Expresión Génica , Hidroximetilglutaril-CoA-Reductasas NADP-Dependientes/química , Riñón/enzimología , Hígado/enzimología , Pulmón/enzimología , Datos de Secuencia Molecular , Mutación , Sistemas de Lectura Abierta , Polimorfismo de Nucleótido Simple , Conformación Proteica , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Vejiga Urinaria/enzimología , Útero/enzimologíaRESUMEN
The association of polymorphisms in peroxisome proliferator-activated receptor γ (PPARγ) gene with litter size was studied in Large White and Landrace pig. Three SNP loci (P1, P2 and P7) on PPARγ(2) gene were determined by PCR-SSCP and the results showed that there were A â G mutations at 220 and 324 bp in 5'-regulator region and at 147 bp in exon 6, respectively. Allele frequencies were analysed in two breeds. Information on 2341 litter records from 564 sows was used to analyse the trait total number born (TNB) and number born alive (NBA). In Large White, TNB and NBA of genotype BB for P2 locus were the lowest, and the TNB and NBA of third and following parities and all parities were 0.74 and 0.51 piglets per litter less (P < 0.001) than those of the highest genotype AB, respectively, but for P1 and P7 locus the beneficial genotype AA were more 0.4-0.8 piglets per litter (P < 0.05) than the inferior genotype AB. In landrace, TNB and NBA of the first parity of genotype BB for P1 locus were 2.0 piglets per litter higher than AA (P < 0.05), but for all parities the TNB and NBA of genotype BB were 0.66 and 0.97 piglets per litter (P < 0.05) higher than AA, respectively. At P2 locus, the TNB and NBA of the second parity of genotype AA were obviously higher than those of AB (P < 0.05). And at P7 locus, the TNB and NBA of each parity of genotype AA were both about 2 piglets per litter more than those of BB (P < 0.05). The results indicated that PPARγ gene was significantly associated with litter size in pigs.