Corona is required for higher-order assembly of transverse filaments into full-length synaptonemal complex in Drosophila oocytes.
Corona is required for higher-order assembly of transverse filaments into full-length synaptonemal complex in Drosophila oocytes.
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DOI：
10.1371/journal.pgen.1000194
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发表时间：
2008-09-19
期刊：
影响因子：
4.5
通讯作者：
Hawley RS
中科院分区：
文献类型：
--
作者：
Page SL;Khetani RS;Lake CM;Nielsen RJ;Jeffress JK;Warren WD;Bickel SE;Hawley RS
联会复合体（synaptonemal complex，SC）是减数分裂前期同源染色体之间形成的一种复杂结构，它介导同源染色体配对的相互作用，促进遗传交换的形成。在果蝇中，C（3）G蛋白形成SC的横丝（TF）。C（3）G同源二聚体的N末端定位于SC的中央元件（CE），而C（3）G的C末端通过与SC的轴向元件/侧向元件（AE/LE）的关联将TF连接到染色体。我们发现果蝇蛋白Corona（CONA）以相互依赖的方式与C（3）G共定位，并且在成对同源染色体和缺乏AE/LE的C（3）G多复合物的背景下，是C（3）G聚合成成熟线状结构所必需的。虽然AE在cona卵母细胞中组装，但它们表现出c（3）G突变卵母细胞的特征性缺陷，包括AE对齐和突触的失败。这些结果表明，CONA，它不包含一个卷曲螺旋结构域，是所需的稳定的“拉链”的TF形成的果蝇SC的中心区域。我们推测，CONA的SC形成的作用可能是类似的哺乳动物CE蛋白SYCE 2和TEX 12。然而，AE对齐和配对发生在Tex 12和Syce 2突变的性母细胞，但不是在cona卵母细胞的观察表明，SC在果蝇中的同源物的稳定协会比它在哺乳动物细胞中起着更重要的作用。减数分裂是一种特殊的细胞分裂类型，需要产生精子和卵细胞，它们只携带体内其他细胞染色体数量的一半。减数分裂是生殖所必需的，但减数分裂过程中的错误引起的染色体数目异常是人类许多出生缺陷和智力低下综合征的原因。果蝇（Drosophila melanogaster）是一种研究减数分裂的极好生物体，因为它可以使用强大的遗传和显微技术。在减数分裂早期，同源染色体通过一种称为联会复合体（SC）的复杂蛋白质结构连接在一起，该蛋白质结构在将同源染色体连接在一起和促进减数分裂重组的过程中起着关键作用。在这项研究中，我们发现了一种称为Corona的蛋白质，它是SC形成所必需的。我们的数据表明，Corona是SC蛋白C（3）G正确定位所必需的。C（3）G不能形成SC的中心区域，因此，提高对SC组装和功能的认识将有助于我们更好地理解减数分裂中染色体分离的机制。
The synaptonemal complex (SC) is an intricate structure that forms between homologous chromosomes early during the meiotic prophase, where it mediates homolog pairing interactions and promotes the formation of genetic exchanges. In Drosophila melanogaster, C(3)G protein forms the transverse filaments (TFs) of the SC. The N termini of C(3)G homodimers localize to the Central Element (CE) of the SC, while the C-termini of C(3)G connect the TFs to the chromosomes via associations with the axial elements/lateral elements (AEs/LEs) of the SC. Here, we show that the Drosophila protein Corona (CONA) co-localizes with C(3)G in a mutually dependent fashion and is required for the polymerization of C(3)G into mature thread-like structures, in the context both of paired homologous chromosomes and of C(3)G polycomplexes that lack AEs/LEs. Although AEs assemble in cona oocytes, they exhibit defects that are characteristic of c(3)G mutant oocytes, including failure of AE alignment and synapsis. These results demonstrate that CONA, which does not contain a coiled coil domain, is required for the stable ‘zippering’ of TFs to form the central region of the Drosophila SC. We speculate that CONA's role in SC formation may be similar to that of the mammalian CE proteins SYCE2 and TEX12. However, the observation that AE alignment and pairing occurs in Tex12 and Syce2 mutant meiocytes but not in cona oocytes suggests that the SC plays a more critical role in the stable association of homologs in Drosophila than it does in mammalian cells. Meiosis is a specialized type of cell division that is needed to produce sperm and egg cells, which carry only half the number of chromosomes of other cells in the body. Meiosis is required for reproduction, but abnormalities in chromosome number caused by errors in the process of meiosis are responsible for many birth defects and mental retardation syndromes in humans. The fruit fly, Drosophila melanogaster, is an excellent organism in which to study meiosis because of the powerful genetic and microscopic techniques that can be implemented with it. Early in meiosis, homologous chromosomes are joined together by an elaborate protein structure called the synaptonemal complex (SC) that plays a critical role in both holding homologous chromosomes together and in facilitating a process known as meiotic recombination. In this study, we have found a protein called Corona that is required for the formation of the SC. Our data show that Corona is required for the proper localization of the SC protein C(3)G. In the absence of Corona, C(3)G fails to polymerize and form the central region of the SC. Increasing our understanding of SC assembly and function will lead to a better understanding of the mechanism for proper chromosome segregation during meiosis.
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影响因子：
14.9
作者：
Grumbling G;Strelets V
通讯作者：
Strelets V
DOI：
10.1083/jcb.141.1.5
发表时间：
1998-04-06
期刊：
The Journal of cell biology
影响因子：
--
作者：
Fung JC;Marshall WF;Dernburg A;Agard DA;Sedat JW
通讯作者：
Sedat JW
DOI：
10.1073/pnas.0500172102
发表时间：
2005-03-22
影响因子：
11.1
作者：
Anderson, LK;Royer, SM;Hawley, RS
通讯作者：
Hawley, RS
影响因子：
11.8
作者：
Colaiácovo, MP;MacQueen, AJ;Villeneuve, AM
通讯作者：
Villeneuve, AM
影响因子：
10.5
作者：
LANTZ, V;CHANG, JS;SCHEDL, P
通讯作者：
SCHEDL, P