Multiple AGAMOUS homologs from cucumber and petunia differ in their ability to induce reproductive organ fate
Multiple AGAMOUS homologs from cucumber and petunia differ in their ability to induce reproductive organ fate
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DOI：
10.1105/tpc.10.2.171
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发表时间：
1998-02-01
期刊：
影响因子：
11.6
通讯作者：
Angenent, GC
中科院分区：
文献类型：
--
作者：
Kater, MM;Colombo, L;Angenent, GC
在拟南芥中，C基因的功能决定了雄蕊和心皮的身份，它由一个名为AGAMOUS （AG）的基因代表。从矮牵牛和黄瓜中分离出两个MADS盒子基因。两者都与拟南芥AG蛋白具有高度的氨基酸序列一致性。通过在矮牵牛中异位表达，研究了它们在雄蕊和心皮鉴定中的作用，从而使植物具有不同的花型。黄瓜MADS box基因1 （CUM1）诱导萼片向核样结构转化，花瓣向雄蕊转变，这与拟南芥中异位AG的表达相似。黄瓜AG的另一个同源物CUM10的过表达导致花瓣部分转化为类花药结构，这表明CUM10也能促进花器官的同一性。从矮牵牛花AG的两个同源基因pMADS3和花结合蛋白基因6 （FBP6）中，只有pMADS3能够诱导萼片和花瓣的同源转化。pMADS3和FBP6的异位表达，正如在矮牵牛花同源突变体盲体中发生的那样，表型上显示了pMADS3单一过表达植株，表明协同表达不存在加性效应。本研究表明，在矮牵牛和黄瓜中，存在多个AG同源物，尽管它们诱导生殖器官命运的能力不同。
The C function in Arabidopsis, which specifies stamen and carpel identity, is represented by a single gene called AGAMOUS (AG). From both petunia and cucumber, two MADS box genes have been isolated. Both share a high degree of amino acid sequence identity with the Arabidopsis AG protein. Their roles in specifying stamen and carpel identity have been studied by ectopic expression in petunia, resulting in plants with different floral phenotypes. Cucumber MADS box gene 1 (CUM1) induced severe homeotic transformations of sepals into carpelloid structures and petals into stamens, which is similar to ectopic AG expression in Arabidopsis plants. Overexpression of the other cucumber AG homolog, CUM10, resulted in plants with partial transformations of the petals into antheroid structures, indicating that CUM10 is is also able to promote floral organ identity. From the two petunia AG homologs pMADS3 and Floral Binding Protein gene 6 (FBP6), only pMADS3 was able to induce homeotic transformations of sepals and petals. Ectopic expression of both pMADS3 and FBP6, as occurrs in the petunia homeotic mutant blind, phenocopies the pMADS3 single overexpresser plants, indicating that there is no additive effect of concerted expression. This study demonstrates that in petunia and cucumber, multiple AG homologs exist, although they differ in their ability to induce reproductive organ fate.