Ascidian Sexual Reproductive Strategies: Mechanisms of Sperm-Egg Interaction and Self-Sterility
Ascidian Sexual Reproductive Strategies: Mechanisms of Sperm-Egg Interaction and Self-Sterility
复制标题
海鞘有性生殖策略：精卵相互作用和自体不育的机制
DOI：
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Maki Shirae‐Kurabayashi
中科院分区：
文献类型：
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作者：
H. Sawada;Shiori Nakazawa;Maki Shirae‐Kurabayashi
海鞘（原脊索动物）是雌雄同体，几乎同时释放精子和卵子。然而，在许多海鞘物种中，包括Ciona robusta（原名：Ciona intetsinalis type A）和Halocynthia roretzi，精子与卵的卵黄层（VC）之间的相互作用期间，自花受精被自不育机制所禁止。最近的一项遗传学研究表明，C。robusta揭示了基因座A和B中的两个紧密连锁的基因对，即，精子PKDREJ样受体s-Themis-A和VC纤维蛋白原样配体v-Themis-A，以及s-Themis-B和v-Themis-B，其包括个体间的高度可变区，负责自我识别。当s/v-Themis-A和s/v-Themis-B的两个等位基因具有相同的单倍型时，精子将卵子识别为自体卵子。当精子附着在自体卵VC上时，精子头部和鞭毛可能通过s-Themis-B C端的Ca ~（2+）传导阳离子通道发生剧烈的Ca ~（2+）内流，导致精子脱离VC或精子活力下降。我们最近确定了v-Themis样，一种没有等位基因多态性的酸可提取VC蛋白，作为一种新的候选人，参与自我不育。这种自交不育机制与被子植物的自交不亲和系统密切相关。一个不同的海鞘，Halocynthia roretzi，利用不同的自我/非自我识别系统在受精过程中，使用EGF样重复含有VC蛋白，HrVC 70。此外，还对H. roretzi包含四对s/v-Themis同源物。这些基因产物也可能在该物种的自交不育中发挥作用。本章介绍了海鞘受精过程中配子相互作用和自我/非自我识别机制的历史和现状。
Ascidians (protochordate) are hermaphrodites that release sperm and eggs nearly simultaneously. However, self-fertilization is prohibited by self-sterility mechanisms during interaction between sperm and the vitelline coat (VC) of the eggs in many ascidian species, including Ciona robusta(former name: Ciona intetsinalis type A) and Halocynthia roretzi. A recent genetic study in C. robusta revealed that two tightly linked gene pairs in loci A and B, i.e., the sperm PKDREJ-like receptor s-Themis-A and the VC fibrinogen-like ligand v-Themis-A, and s-Themis-B and v-Themis-B, which include highly variable regions among individuals, are responsible for self-recognition. Sperm recognizes an egg as a self-egg when both alleles of s/v-Themis-A and s/v-Themis-B possess the same haplotypes. When attached to the VC of self-eggs, acute and drastic Ca2+ influx takes place in the sperm head and flagella probably via the Ca2+-conducting cation channel in the C-terminal region of s-Themis-B, which results in sperm detachment from the VC or decrease in sperm motility. We recently identified v-Themis-like, an acid-extractable VC protein with no allelic polymorphism, as a new candidate that participates in self-sterility. This self-sterility mechanism is closely related to the self-incompatibility systems in angiosperms. A different ascidian, Halocynthia roretzi, utilizes a different self/nonself-recognition system during fertilization, using an EGF-like repeat-containing VC protein, HrVC70. Moreover, the genome database of H. roretzi contains four pairs of s/v-Themis homologs. These gene products may also play a role in self-sterility in this species. This chapter describes the historic and current understandings of the mechanisms of gamete interaction and self/nonself-recognition in ascidian fertilization.
尾索动物海鞘中血液系统的形成需要可变受体 vCRL1
影响因子：
10.7
作者：
Sommer F;Awazu S;Anton-Erxleben F;Jiang D;Klimovich AV;Klimovich BV;Samoilovich MP;Satou Y;Krüss M;Gelhaus C;Kürn U;Bosch TC;Khalturin K
通讯作者：
Khalturin K
影响因子：
7.2
作者：
V. Vacquier;W. Swanson
通讯作者：
V. Vacquier;W. Swanson
卵果冻的岩藻糖硫酸聚合物与精子 REJ 结合，是海胆精子顶体反应的诱导剂。
影响因子：
2.7
作者：
Vacquier,VD;Moy,GW
通讯作者：
Moy,GW