IRX3基因在秦川牛不同组织中的表达分析

Expression of IRX3 gene in different tissues of Qinchuan cattle

【目的】研究IRX3(Iroquois homeobox 3)基因在秦川牛各组织中的表达规律,为通过现代分子技术手段改良秦川牛肉用性状提供理论依据。【方法】根据秦川牛IRX3的mRNA序列设计实时定量特异性引物,采用实时荧光定量PCR方法,检测IRX3基因在秦川牛不同生长发育阶段(胎儿、6月龄、24月龄)不同组织(心脏、肝脏、脾脏、肺脏、肾脏、大肠、小肠、肌肉(背最长肌))及在6月龄、18月龄、24月龄、60月龄秦川牛脂肪组织中的表达水平。【结果】IRX3基因在秦川牛胎牛、6月龄、24月龄3个阶段均在肺部组织中表达量最高(P<0.01)。IRX3基因在秦川牛心脏、肝脏中的表达量随年龄的增长而极显著增加(P<0.01);在背最长肌中的表达量随生长发育过程的推进而极显著减少(P<0.01);在大肠、肺脏组织中的表达量从胎牛到6月龄逐渐降低,从6月龄到24月龄极显著增加(P<0.01)。随着年龄的增长,秦川牛脂肪组织中IRX3基因的表达量呈先升高后降低最后再升高的变化趋势,18月龄表达量最高,极显著高于其他年龄段(P<0.01);其次是6月龄,表达量极显著高于24~60月龄(P<0.01)。【结论】IRX3基因在不同阶段秦川牛的肺部组织中均有较高水平的表达;IRX3基因在脂肪组织中的表达量与牛生长速度正相关,推测IRX3基因在秦川牛发育过程中与脂肪沉积有密切联系。

【Objective】This study investigated the expression patterns of IRX3（Iroquois homeobox 3）gene in Qinchuan cattle tissues to provide basis for meat trait improvement through modern molecular technology.【Method】Real-time quantitative specific primers were designed based on the mRNA sequence of IRX3 gene,and SYBR green reaction system of real-time fluorescent quantitative PCR was used to detect the expression level of IRX3 gene in different tissues（heart,liver,spleen,lung,kidney,large intestine,small intestine,and muscle（longissimus dorsi muscle））in different growth stages（fetal bovine,6-month,and 24-month）and in fat tissues at four periods（6-month,18-month,24-month,and 60-month）.【Result】The expression of IRX3 gene in lung was much higher than in other tissues in fetal bovine,6-month and24-month Qinchuan cattle（P〈0.01）.The expressions of IRX3 in heart and liver were low initially and then increased persistently（P〈0.01）.The expression in muscle decreased with the process of growth（P〈0.01）.The expressions of IRX3 in large intestine and lung decreased gradually from fetal bovine to 6-month Qinchuan cattle（P〈0.01）,and increased significantly from 6-month to 24-month（P〈0.01）.With the increase of age,the expression of IRX3 gene in Qinchuan cattle in adipose increased firstly and then decreased before final increase.The highest expression was in 18-month（P〈0.01）,followed by in 6-month（P〈0.01）.【Conclusion】The IRX3 gene had high expression in lung in different periods and its expression in fat was proportional to the growth rate of Qinchuan cattle.Thus,IRX3 gene had close connection with fat deposition during the development of Qinchuan cattle.