BMP signaling regulates the dorsal planarian midline and is needed for asymmetric regeneration
BMP signaling regulates the dorsal planarian midline and is needed for asymmetric regeneration
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DOI：
10.1242/dev.007138
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发表时间：
2007-11-15
期刊：
影响因子：
4.6
通讯作者：
Alvarado, Alejandro Sanchez
中科院分区：
文献类型：
--
作者：
Reddien, Peter W.;Bermange, Adam L.;Alvarado, Alejandro Sanchez
行星动物可以被切割成形状不规则的碎片，能够再生出新的、完整的有机体。这种再生能力包括恢复双边对称性的强大能力。我们已经确定了两侧不对称片段再生缺失身体部位所需的三个基因。这些基因是控制许多动物胚胎背腹模式的信号通路的候选成分：BMP1/Tolloid样基因(smedolloid-1)、Smad4样基因(smedsmad4-1)和BMP2/4/DPP样基因(smedbmp4-1)。BMP信号参与了再生中线新组织的形成、新组织的背腹构型，以及维持现有成体组织的背腹构型的稳态。Smedbmp4-1在背中线正常表达。缺乏中线的不对称片段在再生突起(胚泡)形成之前显示了新的smedbmp4-1表达。含有中线的不对称片段向伤口方向显示smedbmp4-1的表达。我们建议，缺乏左右对称性的受损动物通过调节BMP活性来重置其中线，作为再生过程中早期和必要的事件。
Planarians can be cut into irregularly shaped fragments capable of regenerating new and complete organisms. Such regenerative capacities involve a robust ability to restore bilateral symmetry. We have identified three genes needed for bilaterally asymmetric fragments to regenerate missing body parts. These genes are candidate components of a signaling pathway that controls the dorsal-ventral patterning of many animal embryos: a BMP1/Tolloid-like gene ( smedolloid-1), a SMAD4-like gene ( smedsmad4-1), and a BMP2/4/DPP-like gene ( smedbmp4-1). BMP signaling was involved in the formation of new tissues at the midline of regeneration, the dorsal-ventral patterning of new tissues, and the maintenance of the dorsal-ventral pattern of existing adult tissue in homeostasis. smedbmp4-1 was normally expressed at the dorsal midline. Asymmetric fragments lacking a midline displayed new smedbmp4-1 expression prior to formation of a regenerative outgrowth ( blastema). Asymmetric fragments containing the midline displayed expanded smedbmp4-1 expression towards the wound. We suggest injured animals that lack left-right symmetry reset their midline through modulation of BMP activity as an early and necessary event in regeneration.