CAJ | 학술논문

选取不同日龄的雄性哈萨克羊和新疆细毛羊共54只,屠宰后取背最长肌,用索氏抽提法检测肌内脂肪(intramuscular fat,IMF)含量,用荧光实时定量PCR法检测肌肉脂肪酸合成酶(fatty acid synthase,FAS)和激素敏感脂肪酶(hormone-sensitive lipase,HSL)基因表达的发育性变化,并分析基因表达对肌内脂肪沉积的影响.结果表明:1)随着日龄的增加,雄性哈萨克羊的IMF含量持续上升,各生长时期差异显著(P＜0.05),而新疆细毛羊的IMF含量在各生长时期无显著差异(P＞0.05).雄性哈萨克羊的IMF含量30～90日龄期间极显著高于新疆细毛羊(P＜0.01).2)FAS基因mRNA水平在哈萨克羊肌肉中初生时最高(P＜0.05),然后随日龄的增加呈下降趋势;在新疆细毛羊肌肉中,FAS mRNA水平表现出"下降-上升-下降-上升"的发育模式,其中60日龄显著高于90日龄(P＜0.05),其余日龄之间差异不显著.HSL基因在2品种绵羊肌肉中的表达模式基本类似,在哈萨克羊肌肉中随年龄的增加而下降,初生时的水平显著高于60～90日龄(P＜0.05);在新疆细毛羊中30日龄时达到最高(P＜0.01),到60日龄时下降到最低(P＜0.05),随后保持这种低表达水平.3)FAS和HSL基因mRNA的表达量均与哈萨克羊IMF含量呈负相关,相关系数分别为:r=-0.485(P=0.02),r=0.423(P=0.05);在哈萨克羊中两基因表达量水平比值(FAS:HSL)与IMF呈极显著负相关r=0.552(P=0.01).在新疆细毛羊中两基因的表达水平及比值均与IMF无显著相关性(P＞0.05).
선취불동일령적웅성합살극양화신강세모양공54지,도재후취배최장기,용색씨추제법검측기내지방(intramuscular fat,IMF)함량,용형광실시정량PCR법검측기육지방산합성매(fatty acid synthase,FAS)화격소민감지방매(hormone-sensitive lipase,HSL)기인표체적발육성변화,병분석기인표체대기내지방침적적영향.결과표명:1)수착일령적증가,웅성합살극양적IMF함량지속상승,각생장시기차이현저(P＜0.05),이신강세모양적IMF함량재각생장시기무현저차이(P＞0.05).웅성합살극양적IMF함량30～90일령기간겁현저고우신강세모양(P＜0.01).2)FAS기인mRNA수평재합살극양기육중초생시최고(P＜0.05),연후수일령적증가정하강추세;재신강세모양기육중,FAS mRNA수평표현출"하강-상승-하강-상승"적발육모식,기중60일령현저고우90일령(P＜0.05),기여일령지간차이불현저.HSL기인재2품충면양기육중적표체모식기본유사,재합살극양기육중수년령적증가이하강,초생시적수평현저고우60～90일령(P＜0.05);재신강세모양중30일령시체도최고(P＜0.01),도60일령시하강도최저(P＜0.05),수후보지저충저표체수평.3)FAS화HSL기인mRNA적표체량균여합살극양IMF함량정부상관,상관계수분별위:r=-0.485(P=0.02),r=0.423(P=0.05);재합살극양중량기인표체량수평비치(FAS:HSL)여IMF정겁현저부상관r=0.552(P=0.01).재신강세모양중량기인적표체수평급비치균여IMF무현저상관성(P＞0.05).
Twenty-four male Kazak sheep and 30 Xinjiang fine wool sheep at different ages were selected to investgate the development-dependent expression levels of fatty acid synthase (FAS) gene and hormone-sensitive lipase (HSL) gene in muscle and their effects on the contents of intramuscular fat (IMF). Longissimus dorsal muscle was sampled to measure IMF and total RNA was extracted to determine FAS and HSL mRNA expression levels by real-time PCR. The results showed that: 1) The IMF content increased continuously with growth and showed significant differences (P ＜ 0.05) between different age groups in male Kazak sheep,but in Xinjiang fine wool sheep there was no such difference observed. Furthermore, the IMF contents in Kazak were much higher (P ＜ 0.01) than that of the other breed from day 30 to 90. 2) FAS mRNA expression level was the highest (P ＜ 0.05) on day 0 in the animals grew. HSL mRNA expression level had a similar model in two breeds, in Kazak sheep it was the highest on day 0 (P ＜0.05) and in Xinjiang fine wool sheep on day 30 (P ＜ 0.01), then both decreased after this term. 3) In male Kazak sheep, FAS and HSL mRNA expression level were both negatively related to IMF content (r= -0.485 (P = 0.02), r= -0.423 (P = 0.05)), and the ratio of FAS/HSL expression exhibited significantly negatively related IMF contents. In male Xinjiang sheep, there were no obvious relationship between FAS and HSL expression and IMF content (P ＞ 0.05).