Creation of chimeric mutant axolotls: a model to study early embryonic heart development in Mexican axolotls.
Creation of chimeric mutant axolotls: a model to study early embryonic heart development in Mexican axolotls.
复制标题
嵌合突变蝾螈的创建：研究墨西哥蝾螈早期胚胎心脏发育的模型。
DOI：
10.1007/s004290100158
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Huang,X
中科院分区：
文献类型：
--
作者：
Lemanski,LF;Meng,F;Lemanski,SL;Dawson,N;Zhang,C;Foster,D;Li,Q;Nakatsugawa,M;Zajdel,RW;Dube,DK;Huang,X
墨西哥蝾螈（Ambystoma mexicanum）为研究心脏发育提供了一个极好的模型，因为它在基因中携带心脏致死突变，导致突变胚胎心肌收缩失败。在心脏突变蝾螈（c/c）中，心脏不跳动，显然是因为缺乏有组织的肌原纤维。迄今为止，还没有办法分析杂合产卵 (+/c×+/c) 胚胎的基因型，直到第 35 阶段，此时正常 (+/cor +/+) 胚胎首先开始有跳动的心脏；突变（c/c）胚胎无法发育出正常的心跳。在本研究中，我们利用显微外科技术创造了嵌合蝾螈。一般的方法是横切尾芽胚胎并将两个不同个体的前半部和后半部连接起来。嵌合蝾螈由允许生存的正常头部和心脏区域（+/+）和含有突变性腺的突变体（c/c）组成，该突变体允许产生c/c突变体后代：通过交配c/c嵌合体（c/c×c/c）获得100%c/coffspring。突变表型通过 100% 胚胎在第 41 阶段没有心脏跳动和死亡得到证实。原肌球蛋白免疫荧光染色后，用电子显微镜和共焦显微镜检查突变心脏，显示出与之前在自然发生/突变蝾螈中描述的图像相同的图像（即，缺乏有组织的肌节肌原纤维）。这些“c/cchimeric”蝾螈提供了一种有用且独特的方法来研究心脏突变墨西哥蝾螈的早期胚胎心脏发育。
The Mexican axolotl (Ambystoma mexicanum) provides an excellent model for studying heart development since it carries a cardiac lethal mutation in genecthat results in failure of contraction of mutant embryonic myocardium. In cardiac mutant axolotls (c/c) the hearts do not beat, apparently because of an absence of organized myofibrils. To date, there has been no way to analyze the genotypes of embryos from heterozygous spawnings (+/c×+/c) until stage 35 when the normal (+/cor +/+) embryos first begin to have beating hearts; mutant (c/c) embryos fail to develop normal heartbeats. In the present study, we created chimeric axolotls by using microsurgical techniques. The general approach was to transect tailbud embryos and join the anterior and posterior halves of two different individuals. The chimeric axolotl is composed of a normal head and heart region (+/+), permitting survival and a mutant body containing mutant gonads (c/c) that permits the production ofc/cmutant offspring: 100%c/coffspring were obtained by matingc/cchimeras (c/c×c/c). The mutant phenotypes were confirmed by the absence of beating hearts and death at stage 41 in 100% of the embryos. Examination of the mutant hearts with electron microscopy and comfocal microscopy after immunofluorescent staining for tropomyosin showed identical images to those described previously in naturally-occurringc/cmutant axolotls (i.e., lacking organized sarcomeric myofibrils). These ”c/cchimeric” axolotls provide a useful and unique way to investigate early embryonic heart development in cardiac mutant Mexican axolotls.