乳鼠心肌组织中细胞周期素A2的定位及表达

Location and expression of cyclin A2 in neonatal mouse myocardium

背景:细胞周期素A2是调节细胞周期的关键因子,关于细胞周期素A2在乳鼠心肌中的表达及定位情况还不明确。目的:探索细胞周期素A2在C57乳鼠中的表达定位及表达,检测心肌细胞中增殖相关蛋白随着细胞周期素A2的表达而呈现的表达趋势。方法:C57乳鼠分别于出生后0,3,7,14,28 d处死,留取心肌组织,行Western blot检测心肌组织中细胞周期素A2、增殖细胞核抗原及磷酸组蛋白H3的表达情况。免疫组化检测细胞周期素A2在出生后乳鼠中的定位及增殖细胞核抗原在心肌组织中的表达。结果与结论:C57乳鼠出生后细胞周期素A2表达水平逐渐下调,直至第14天基本消失(P=0.001),且细胞周期素A2在乳鼠出生后0 d定位于细胞核中,在第14天时主要存在于细胞质中,至第28天时,基本消失。增殖细胞核抗原在出生后0 d表达最强,随后表达逐渐减弱。而反映有丝分裂期的特异性蛋白磷酸组蛋白H3随时间表达逐渐减少,且表达强度基本与细胞周期素A2表达减弱相一致。

BACKGROUND： Cyclin A2 is a key regulator of cell cycle. Location and expression of cyclin A2 in neonatal mouse myocardium is not clear. OBJECTIVE： To observe the location and expression of cyclin A2 in neonatal mouse cardiomyocytes and its relationship with the exit of cardiomyocytes from cell cycle. METHODS： Neonatal mice were killed to take myocardial tissues at 0, 3, 7, 14 and 28 days after birth. Western blot were used to detect the expression of cyclin A2, proliferating cell nucleus antigen and Phospho-histone H3. Immunohistochemitry detection was used to detect the location of cyclin A2 and expression of proliferation cell nucleus antigen at different time after birth. RESULTS AND CONCLUSION： Western blot showed the decrease of cyclin A2 after birth till disappeared at day 4 （P=0.001）. Cyclin A2 located mainly in the nucleus after birth and exported to the cytoplasm at day 14, and basically disappeared at day 28. Proliferating cell nucleus antigen showed gradually decreased tendency after birth. Mitosis specific marker, Phospho-histone H3, exhibited a gradual decrease after birth, which was consistent with cyclin A2 in expression intensity.