Koriyama Kazuki, Sakagami Risa, Myouga Ayumi, Hayashi Toshinori, Takeuchi Takashi
Division of Biosignaling, School of Life Sciences, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
Dev Dyn. 2018 Dec;247(12):1276-1285. doi: 10.1002/dvdy.24685. Epub 2018 Nov 22.
Urodele animals can regenerate their limbs from the blastemas. The previous results of grafting proximal blastemas to distal limb levels (P to D transplantation) led to serial duplication of limb segments. However, it is unknown whether grafting to any distal levels in P to D transplantation causes serial duplication. In other words, it is unknown whether or not newt limbs can normalize such a kind of duplicated type of positional disorder in the proximal-distal axis. Therefore, we grafted the most proximal blastemas to various distal levels of the proximal-distal axis using newts (Pleurodeles waltl). The transgenic newts expressing green fluorescent protein or mCherry were used to clearly distinguish between donor and host tissues.
Normal segmental formation without duplication occurred in P to D transplantation within the stylopod. In addition, donor blastemas lost the fates of the stylopods, and the missing portion in the stylopod by amputation was restored by the insertion of host cells. In contrast, the blastemas from the stylopod formed whole limbs after transplantation to the tail.
These results showed that urodele limbs can normalize the duplicated type of positional disorder within the stylopod by erasing a part of the fate in the blastemas. Developmental Dynamics 247:1276-1285, 2018. © 2018 Wiley Periodicals, Inc.
有尾两栖动物能够从芽基再生出肢体。先前将近端芽基移植到肢体远端水平（P到D移植）的结果导致了肢体节段的系列重复。然而，在P到D移植中移植到任何远端水平是否会导致系列重复尚不清楚。换句话说，蝾螈肢体是否能够使这种在近端-远端轴上的重复类型的位置紊乱正常化尚不清楚。因此，我们使用蝾螈（虎纹钝口螈）将最近端的芽基移植到近端-远端轴的不同远端水平。使用表达绿色荧光蛋白或mCherry的转基因蝾螈来清楚地区分供体和宿主组织。
在肱（股）部内的P到D移植中发生了无重复的正常节段形成。此外，供体芽基失去了肱（股）部的命运，并且通过宿主细胞的插入恢复了截肢后肱（股）部中缺失的部分。相反，来自肱（股）部的芽基在移植到尾部后形成了完整的肢体。
这些结果表明，有尾两栖动物的肢体可以通过消除芽基中的部分命运来使肱（股）部内重复类型的位置紊乱正常化。《发育动力学》247:1276 - 1285，2018年。©2018威利期刊公司。
