Exploring embryonic germ line development in the water flea, Daphnia magna, by zinc-finger-containing VASA as a marker
Exploring embryonic germ line development in the water flea, Daphnia magna, by zinc-finger-containing VASA as a marker
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DOI：
10.1016/j.modgep.2005.02.007
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发表时间：
2005-06-01
影响因子：
1.2
通讯作者：
Shiga, Y
中科院分区：
文献类型：
--
作者：
Sagawa, K;Yamagata, H;Shiga, Y
VASA是一种atp依赖的RNA解旋酶，属于DEAD-box家族，在许多生物体中，在整个生命周期中特异性表达生殖系细胞，使其成为研究生殖系发育的有力分子标记。为了进一步了解甲壳类动物生殖系发育的相关信息，我们克隆了3种支足类动物（水蚤Daphnia magna和Moina macrocopa）和咸虾Artemia franciscana)的VASA cdna。支足动物VASA的RNA解旋酶结构域在节肢动物中高度保守。然而，枝足动物VASA的n端rna结合结构域高度分化，并且与迄今为止报道的其他节肢动物VASA不同，它具有逆转录病毒型锌指（CCHC）基元的重复。对水蚤VASA的特异性抗体的培养表明，该生物的原始生殖细胞（PGCs）在孤雌生殖和有性生殖的胚胎发生的早期卵裂阶段分离。然后，成群的PGCs开始在胚胎内迁移，最终定居在肠道两侧，这是未来性腺发育的地方。RNA分析表明，母体提供的vasa mRNA负责vasa的早期表达，而合子表达始于胚层发育阶段。(c) 2005 Elsevier B.V.版权所有
VASA is an ATP-dependent RNA helicase belonging to the DEAD-box family that, in many organisms, is specifically expressed in germ line cells throughout the life cycle, making it a powerful molecular marker to study germ line development. To obtain further information on germ line development in crustaceans, we cloned VASA cDNAs from three branchiopod species: water fleas Daphnia magna and Moina macrocopa, and brine shrimp Artemia franciscana. RNA helicase domains in branchiopod VASA were highly conserved among arthropod classes. However, N-terminal RNA-binding domains in branchiopod VASA were highly diverged and, unlike other arthropod VASA reported so far, possessed repeats of retroviral-type zinc finger (CCHC) motifs. Raising specific antibodies against Daphnia VASA revealed that the primordial germ cells (PGCs) in this organism segregate at a very early cleavage stage of embryogenesis in parthenogenetic and sexual eggs. Clusters of PGCs then start to migrate inside the embryo and finally settle at both sides of the intestine, the site of future gonad development. RNA analyses suggested that maternally supplied vasa mRNA was responsible for early VASA expression, while zygotic expression started during blastodermal stage of development. (c) 2005 Elsevier B.V. All rights reserved.