Development of the swimming acorn worm Glandiceps hacksi: similarity to holothroids.
Development of the swimming acorn worm Glandiceps hacksi: similarity to holothroids.
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游泳橡实蠕虫 Glandiceps hacksi 的发育：与全息肉相似。
DOI：
10.1111/ede.12075
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发表时间：
2014
影响因子：
2.9
通讯作者：
M.
中科院分区：
文献类型：
--
作者：
Urata;M;Iwasaki;S.;Ohtsuka;S.;and Yamaguchi;M.
在实验室中通过短暂的温度升高刺激了glandiceps hacksi（半纲：Enteropneusta）的产卵，并首次描述了Spengelidae科成员从受精到变态的发育过程。当受精时，产生的雌性配子，即初级卵母细胞，迅速形成受精膜并经历两次成熟分裂。全胚，放射状卵裂产生囊胚；然后从植物极内陷形成原肠胚，胚孔随后很快闭合。在先前描述的enternest胚胎中，在原肠芽胞通过鼻孔连接到外部之前，原肠芽胞脱离原肠芽胞。相比之下，inG。在协议形成之前，母体就已经早熟地与外部连接。此后不久，胚胎变得均匀纤毛，然后在大约32小时（15°C培养温度）从受精包膜中孵化。在发育的第3天，原肠从肠道中分离出来，形成一个面向外部的口；此时，肠道已分化为食道、胃和肠，后者向后方张开，形成肛门。幼虫生长形成沿其纤毛带具有独特色素斑块的蛹。
Spawnings ofGlandiceps hacksi(Hemichordata: Enteropneusta) were stimulated in the laboratory by a brief increase in temperature, and the development from fertilization through metamorphosis is described for the first time for a member of the family Spengelidae. When fertilized, the spawned female gametes, which are primary oocytes, rapidly raise a fertilization membrane and undergo two maturation divisions. Holoblastic, radial cleavage produces a blastula; a gastrula then forms by invagination from the vegetal pole, and the blastopore closes soon thereafter. In previously described enteropneust embryos, the archenteron buds off the protocoel before the latter connects to the exterior via the proboscis pore. By contrast, inG. hacksithe archenteron precociously connects with the exterior before the protocoel forms. Soon thereafter, the embryo becomes uniformly ciliated and then hatches from the fertilization envelope at approximately 32 h (15°C culture temperature). At day 3 of development, the protocoel separates from the gut, which establishes a mouth opening to the exterior; by this time, the gut has differentiated into an esophagus, a stomach, and an intestine that opens posteriorly as an anus. The larva grows to form a tornaria with distinctive pigment patches along its ciliary bands.