Mutational analysis of dishevelled genes in zebrafish reveals distinct functions in embryonic patterning and gastrulation cell movements.
Mutational analysis of dishevelled genes in zebrafish reveals distinct functions in embryonic patterning and gastrulation cell movements.
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斑马鱼蓬乱基因的突变分析揭示了胚胎模式和原肠胚细胞运动中的独特功能
DOI：
10.1371/journal.pgen.1007551
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发表时间：
2018-08
期刊：
影响因子：
4.5
通讯作者：
Shi DL
中科院分区：
文献类型：
--
作者：
Xing YY;Cheng XN;Li YL;Zhang C;Saquet A;Liu YY;Shao M;Shi DL
Wnt信号转导在背腹命运特化和前后图案化以及形态发生细胞运动中起着关键作用。紊乱蛋白或Dvl介导Wnt/β-连环蛋白和Wnt/平面细胞极性途径的活化。在脊椎动物中存在至少三种高度保守的Dvl蛋白，但对每种Dvl在关键早期发育过程中的意义仍然知之甚少。在本研究中，我们利用基因组编辑的方法在斑马鱼中产生不同组合的母系和合子dvl突变体，并研究它们在早期发育中的功能。dvl 2和dvl 3a的母体转录物最丰富地表达，而其它dvl基因的转录物水平可忽略不计。表型和分子分析表明，早期的背部命运规范不受影响，在母亲和合子dvl 2和dvl 3a双突变体，这表明这两种蛋白质可能是激活母亲Wnt/β-连环蛋白信号。有趣的是，会聚和伸展运动以及前后图案化需要Dvl 2和Dvl 3a的母体和合子功能，但这些过程对Dvl 2剂量更敏感。合子dvl 2和dvl 3a双突变体显示轻度轴延伸缺陷，具有正确的前后模式。然而，母亲和合子双突变体表现出最强烈受损的收敛和扩展运动，严重的躯干和后部的缺陷，并经常发生独眼畸形和颅面缺陷。我们的研究结果表明，Dvl 2和Dvl 3a产物是激活合子Wnt/β-catenin信号通路和Wnt/平面细胞极性通路所必需的，并以剂量依赖的方式调节合子发育过程。这项工作提供了深入了解Dvl介导的Wnt信号通路在早期脊椎动物发育过程中的机制。大多数动物的胚胎发生首先由卵母细胞中积累的母体基因产物支持，然后由合子中的基因表达支持。在所有脊椎动物中，至少有三种Dishevelled（Dvl）蛋白，它们在正常发育和人类疾病中起着关键作用。它们在母体和合子中表达，并且可以激活调节基因表达和细胞命运的β-连环蛋白依赖性Wnt途径，以及协调细胞运动的β-连环蛋白非依赖性Wnt途径。在斑马鱼胚胎中，Dvl 2和Dvl 3a是最丰富的，但其功能尚未完全了解。我们发现，母系和合子表达Dvl 2起着主导作用，在前后轴的伸长，和参与发展的后区的基因的表达。Dvl 3a在这些过程中与Dvl 2合作。这些基因功能丧失后的分析表明，母体和合子Dvl 2和Dvl 3a的缺乏导致胚胎出现独眼畸形、颅面缺陷以及躯干和后部区域的严重异常。许多人类出生缺陷和其他疾病，如癌症，都归因于Wnt通路的功能障碍。我们的研究结果有助于理解Dvl介导的Wnt通路激活的机制，以及发育障碍的原因。
Wnt signaling plays critical roles in dorsoventral fate specification and anteroposterior patterning, as well as in morphogenetic cell movements. Dishevelled proteins, or Dvls, mediate the activation of Wnt/ß-catenin and Wnt/planar cell polarity pathways. There are at least three highly conserved Dvl proteins in vertebrates, but the implication of each Dvl in key early developmental processes remains poorly understood. In this study, we use genome-editing approach to generate different combinations of maternal and zygotic dvl mutants in zebrafish, and examine their functions during early development. Maternal transcripts for dvl2 and dvl3a are most abundantly expressed, whereas the transcript levels of other dvl genes are negligible. Phenotypic and molecular analyses show that early dorsal fate specification is not affected in maternal and zygotic dvl2 and dvl3a double mutants, suggesting that the two proteins may be dispensable for the activation of maternal Wnt/ß-catenin signaling. Interestingly, convergence and extension movements and anteroposterior patterning require both maternal and the zygotic functions of Dvl2 and Dvl3a, but these processes are more sensitive to Dvl2 dosage. Zygotic dvl2 and dvl3a double mutants display mild axis extension defect with correct anteroposterior patterning. However, maternal and zygotic double mutants exhibit most strongly impaired convergence and extension movements, severe trunk and posterior deficiencies, and frequent occurrence of cyclopia and craniofacial defects. Our results suggest that Dvl2 and Dvl3a products are required for the activation of zygotic Wnt/ß-catenin signaling and Wnt/planar cell polarity pathway, and regulate zygotic developmental processes in a dosage-dependent manner. This work provides insight into the mechanisms of Dvl-mediated Wnt signaling pathways during early vertebrate development. The embryogenesis of most animals is first supported by maternal gene products accumulated in the oocyte, and then by the expression of genes from the zygote. In all vertebrates, there are at least three Dishevelled (Dvl) proteins, which play critical roles in normal development and human diseases. They are both maternally and zygotically expressed, and can activate the ß-catenin-dependent Wnt pathway that regulates gene expression and cell fate, and the ß-catenin-independent Wnt pathway that orchestrates cell movements. In zebrafish embryo, Dvl2 and Dvl3a are most abundant, but their functions are not fully understood. We find that maternally and zygotically expressed Dvl2 plays a predominant role in the elongation of the anteroposterior axis, and the expression of genes involved in the development of the posterior region. Dvl3a cooperates with Dvl2 in these processes. Analyses after loss-of-function of these genes indicate that deficiency of maternal and zygotic Dvl2 and Dvl3a results in embryos with cyclopia, craniofacial defects, and severe abnormality in the trunk and posterior regions. Many human birth defects and other diseases, like cancer, are attributed to the dysfunction of the Wnt pathways. Our results help to understand the mechanisms of Dvl-mediated Wnt pathway activation, and the causes of developmental disorders.
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影响因子：
10.5
作者：
Habas, R;Dawid, IB;He, X
通讯作者：
He, X
影响因子：
21.3
作者：
Angers, S;Thorpe, CJ;Moon, RT
通讯作者：
Moon, RT
影响因子：
4.5
作者：
Etheridge SL;Ray S;Li S;Hamblet NS;Lijam N;Tsang M;Greer J;Kardos N;Wang J;Sussman DJ;Chen P;Wynshaw-Boris A
通讯作者：
Wynshaw-Boris A
影响因子：
2.5
作者：
KIMMEL, CB;BALLARD, WW;SCHILLING, TF
通讯作者：
SCHILLING, TF
Disheveled的构象变化在Wnt信号通路中发挥关键调节作用
影响因子：
7.7
作者：
Lee HJ;Shi DL;Zheng JJ
通讯作者：
Zheng JJ