School of Medical Sciences, Bosch Institute, The University of Sydney, Sydney, NSW, 2006, Australia.
Dev Genes Evol. 2009 Dec;219(11-12):613-8. doi: 10.1007/s00427-010-0318-4. Epub 2010 Feb 25.
Expression of Hox4 during development of the bilateral larva and pentameral juvenile sea star was investigated in Parvulastra exigua. The role of Hox4, possibly the anterior-most gene in the echinoderm Hox cluster, in the formation of the echinoderm adult body plan has not been examined previously. In the larva of P. exigua, PeHox4 is expressed in the developing coeloms-the anterior and the right and left coeloms that generate the aboral and oral coeloms of the juvenile. At the rudiment stage, PeHox4 was expressed in the five primary lobes of the hydrocoel that give rise to primary podia, the foundation of the adult body plan. This suggests a role for this gene in the development of the echinoderm body plan. In contrast to other bilaterians, Hox4 was not expressed in the developing asteroid central nervous system.
研究了 Parvulastra exigua 幼虫双侧和五腕幼体发育过程中 Hox4 的表达。Hox4 可能是棘皮动物 Hox 簇中最靠前的基因，但其在棘皮动物成体体式形成中的作用以前尚未被研究过。在 P. exigua 的幼虫中，PeHox4 在前肠和左右肠中表达，这些肠腔会生成幼体的口肠和肛肠。在原肠胚阶段，PeHox4 在水腔的五个初级叶中表达，这些初级叶会生成初级腕足，这是成体体式的基础。这表明该基因在棘皮动物体式的发育中起作用。与其他两侧对称动物不同，Hox4 没有在发育中的海星中央神经系统中表达。
