低温对民猪骨骼肌线粒体能量代谢基因的影响

Effect of Low Temperature on Mitochondrial Energy Metabolism Genes in Skeletal Muscle of Min Pig

为了探究低温环境下民猪肌肉组织内与线粒体能量代谢相关基因的变化情况,以解析民猪抗寒特性的遗传机制。将9头体质量相近的母猪随机分成3组,每组3头,在冬季将其中2组置于室外半敞篷舍内饲养,分别处理3 d(急性低温处理组)和58 d(慢性低温处理组),1组置于常规舍内饲养,作为对照组。以背肌为试验材料,采用PCR array方法,对90个与线粒体能量代谢相关基因的表达水平进行检测。结果表明,与对照组相比,急性低温处理组基因的表达水平差异不显著,但慢性低温处理显著改变 ATP5H、 ATP5L、 ATP6V1G3、 COX5A、 COX7A2、 COX7A2L、 NDUFS4、 SDHB、 UQCRQ和 GADD45B基因的表达水平,尤其是 GADD45B,达到了极显著水平(P<0.01),这些基因均为编码OXPHOS系统亚基基因,推测慢性低温诱导了背肌ATP的生成。对 GADD45B基因进一步分析发现,该基因在哺乳动物中高度保守,基本符合分子进化规律,表达具有明显的组织特异性。急性低温处理对民猪背肌内ATP的生成影响不显著,但慢性低温处理诱导ATP的生成,以维持体温恒定。

In order to explore the changes of genes related to mitochondrial energy metabolism in muscle tissue of Min pigs under low temperature environment,and to analyze the genetic mechanism of cold resistance of Min pigs.Nine female Min pigs with similar mass were randomly divided into three groups,with three individuals in each group.In winter,two groups of individuals were raised in outdoor semi-open houses for 3 days(acute low temperature treatment group)and 58 days(chronic low temperature treatment group),respectively,and one group was raised in normal houses as the control group.The expression level of 90 genes related to mitochondrial energy metabolism in the skeletal muscle of Min pig was detected by PCR array method.The acute low temperature treatment did not significantly change the expression levels of these genes,but chronic low temperature treatment significantly changed the expression levels of ATP5H,ATP5L,ATP6V1G3,COX5A,COX7A2,COX7A2 L,NDUFS4,SDHB,UQCRQ and GADD45B genes at a very significant level(P<0.01),especially GADD45B.These genes were all genes encoding OXPHOS system subunits,suggesting that chronic low temperature treatment induced ATP production.Further analysis of GADD45B gene showed that the gene was highly conservative in mammals,basically in line with the molecular evolutionary law,and its expression had obvious tissue specificity.Acute low temperature treatment did not change the ATP production in skeletal muscle of Min pig,but the chronic low temperature treatment induced ATP production to maintain body temperature constant.