Epigenetics and Chromatin Remodeling in mammalian early development

反向遗传方法在发育生物学中越来越有吸引力。最近，一种抑制基因功能的策略被证明是非常有效的。morpholinos反义寡核苷酸（morpholinos）通过阻止核糖体与靶mRNA的结合而阻断翻译。使用morpholino被证明是研究斑马鱼和爪蟾胚胎基因功能的一种有价值的工具。然而，很少有研究评估将morpholinos显微注射到哺乳动物卵母细胞中。小鼠卵母细胞特异性连接蛋白H1foo被认为在卵发生和早期胚胎发生过程中对基因表达和染色质修饰的控制起关键作用。为了研究利用morpholinos抑制小鼠基因功能的可行性，我们将抗H1foo的morpholinos微注射到小鼠GV期卵母细胞中。免疫印迹和免疫染色分析显示，注射了H1foo morpholinos的卵母细胞成功抑制了H1foo蛋白的表达，并且注射了H1foo morpholinos组的卵母细胞体外成熟率低于对照组。这一结果表明H1foo对gv期卵母细胞的成熟至关重要。Morpholinos也为研究小鼠发育过程中的基因功能提供了一种有用的方法。

Reverse genetic approaches have become increasingly attractive in developmental biology. Recently, one strategy for inhibiting gene function has been shown to be extremely effective. Morpholino antisense oligonucleotides (morpholinos) block translation by preventing ribosomes from binding to target mRNA. The use of morpholino is proving to be a valuable tool for investigating gene function in zebrafish and xenopus embryos. However, few studies have evaluated the microinjection of morpholinos into mammalian oocytes. The mouse oocyte-specific linker histone H1foo is thought to play a key role in the control of gene expression and chromatin modification during oogenesis and early embryogenesis. To investigate the feasibility of using morpholinos to suppress mouse gene function, we performed the microinjection of morpholinos against H1foo into mouse GV stage oocytes. Immunoblotting and immunostaining analysis showed that the exression of H1foo protein was successfully suppressed in the oocytes injected with H1foo morpholinos, and in H1foo morpholinos injected group, the rate of in vitro maturation was lower than that in control group. This result suggests that H1foo is essential for maturation of GV-stage oocytes. Morpholinos provide a useful method to study gene function also in the mouse development.