Antagonistic gene activities determine the formation of pattern elements along the mediolateral axis of the Arabidopsis fruit.
Antagonistic gene activities determine the formation of pattern elements along the mediolateral axis of the Arabidopsis fruit.
复制标题
DOI：
10.1371/journal.pgen.1003020
复制
发表时间：
2012
期刊：
影响因子：
4.5
通讯作者：
Martínez-Laborda A
中科院分区：
文献类型：
--
作者：
González-Reig S;Ripoll JJ;Vera A;Yanofsky MF;Martínez-Laborda A
拟南芥果实主要由成熟的子房组成，子房显示出三个明确的区域，它们是沿花的内侧轴的图案元素：位于花的内侧平面的质地，以及瓣膜和瓣膜边缘，两者都是横向的。JAG/FIL活性包括锯齿状(JAG)、丝状花(FIL)和YABBY3(YAB3)的组合功能，有助于形成两个侧向模式元件，而协同基因BREVIPEDICELLUS(BP)和REPLUMLESS(RPL)促进质膜发育。最近一个解释沿内外侧轴模式形成的模型假设，JAG/FIL活性和BP/RPL分别作为相互抑制的横向和内侧因子发挥作用。在这项工作中，我们论证了这两种因素之间存在互斥机制，以及这种机制如何决定了这三个领域的形成和大小。中间因子自主地约束侧向因子，使它们只在复核外表达，而侧向因子以非自主的方式负性调节中间表达的BP基因，以确保复核的正确发育。我们还发现，先前在叶片和子房中都能抑制BP的不对称LEAVES1(AS1)与JAG/FIL活性协同作用，阻止了BP的抑制，并与JAG/FIL活性基因显示出协同作用。因此，作为基因功能(相互作用的基因AS1和AS2的功能)作为一个新的侧向因子被纳入到模型中。我们的拮抗因子模型为拟南芥的突变果实表型提供了解释，也可能有助于理解十字花科和其他物种果实形状的自然变异，因为基因表达的细微变化可能会导致不同组织类型的大小明显变化。拟南芥果实的内侧轴有三个主要的花纹元素。其中两个，瓣膜和瓣膜边缘，被放置在横向位置，而第三个，被称为Replum，位于花的内侧平面。复制体表达的分生组织基因(中间因子)规定了它的发育，而叶片中起作用的基因(横向因子)的功能决定了瓣膜和瓣膜边缘的发育。因此，果实的内侧和侧向模式元素明显地模拟了分生组织和叶片之间的拮抗关系。在此基础上，我们提出了一个水果内侧模式的模型，其中内侧因素和侧向因素的相互对立的活动驱动了果瓣、瓣膜和瓣膜边缘的形成。我们的结论是，中间因素以一种自主的方式发挥作用，阻止侧向因素在复核中的表达，而侧向因素通过一种非自主机制抑制中间因素，以允许正常的复盖发育。我们的模型解释了十字花科和相关生物中果实形状的变化，要么是由于物种内的突变，要么是由于不同物种之间的自然变异。
The Arabidopsis fruit mainly consists of a mature ovary that shows three well defined territories that are pattern elements along the mediolateral axis: the replum, located at the medial plane of the flower, and the valve and the valve margin, both of lateral nature. JAG/FIL activity, which includes the combined functions of JAGGED (JAG), FILAMENTOUS FLOWER (FIL), and YABBY3 (YAB3), contributes to the formation of the two lateral pattern elements, whereas the cooperating genes BREVIPEDICELLUS (BP) and REPLUMLESS (RPL) promote replum development. A recent model to explain pattern formation along the mediolateral axis hypothesizes that JAG/FIL activity and BP/RPL function as antagonistic lateral and medial factors, respectively, which tend to repress each other. In this work, we demonstrate the existence of mutual exclusion mechanisms between both kinds of factors, and how this determines the formation and size of the three territories. Medial factors autonomously constrain lateral factors so that they only express outside the replum, and lateral factors negatively regulate the medially expressed BP gene in a non-autonomous fashion to ensure correct replum development. We also have found that ASYMMETRIC LEAVES1 (AS1), previously shown to repress BP both in leaves and ovaries, collaborates with JAG/FIL activity, preventing its repression by BP and showing synergistic interactions with JAG/FIL activity genes. Therefore AS gene function (the function of the interacting genes AS1 and AS2) has been incorporated in the model as a new lateral factor. Our model of antagonistic factors provides explanation for mutant fruit phenotypes in Arabidopsis and also may help to understand natural variation of fruit shape in Brassicaceae and other species, since subtle changes in gene expression may cause conspicuous changes in the size of the different tissue types. There are three main pattern elements in the mediolateral axis of the Arabidopsis fruit. Two of them, the valves and the valve margins, are placed in lateral positions, while the third, called replum, is located in the medial plane of the flower. The replum expresses meristematic genes (medial factors) that specify its development, whereas the function of genes that work in leaves (lateral factors) determines the development of valves and valve margins. Consequently, medial and lateral pattern elements of fruits apparently mimic the antagonistic relationships between meristem and leaves. According to this, we propose a model for mediolateral patterning of fruits whereby the mutual opposing activities of medial and lateral factors drive the formation of replum, valves, and valve margins. We conclude that medial factors function in an autonomous fashion to prevent the expression of lateral factors in the replum, and that lateral factors repress medial factors by a non-autonomous mechanism to allow normal replum development. Our model provides explanation for changes in fruit shape in Brassicaceae and related organisms either by mutation within a species or by natural variation among different species.
登录
查看更多内容
影响因子：
14.9
作者：
Cole, M;Nolte, C;Werr, W
通讯作者：
Werr, W
影响因子：
4.6
作者：
Dinneny, JR;Yadegari, R;Weigel, D
通讯作者：
Weigel, D
影响因子：
4.6
作者：
Brewer, PB;Howles, PA;Smyth, DR
通讯作者：
Smyth, DR
影响因子：
6.9
作者：
Ferr치ndiz, C
通讯作者：
Ferr치ndiz, C
影响因子：
4.6
作者：
Dinneny, JR;Weigel, D;Yanofsky, MF
通讯作者：
Yanofsky, MF