DNA binding properties of two arabidopsis MADS domain proteins: Binding consensus and dimer formation
DNA binding properties of two arabidopsis MADS domain proteins: Binding consensus and dimer formation
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DOI：
10.1105/tpc.8.1.81
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发表时间：
1996-01-01
期刊：
影响因子：
11.6
通讯作者：
Ma, H
中科院分区：
文献类型：
--
作者：
Huang, H;Tudor, M;Ma, H
MADS结构域蛋白是在所有真核生物中发现的高度保守家族的成员。遗传研究清楚地表明，许多植物MADS结构域蛋白在花发育中具有不同的调节功能，但它们共享高度保守的DNA结合结构域，并且可以结合非常相似的序列。那么，这些MADS盒基因是如何赋予它们特定的功能的呢？在这里，我们描述了AGL1和AGL2（AGAMOUS样），优先在花中表达的两个拟南芥MADS结构域蛋白的DNA结合研究的结果，我们证明了这两种蛋白质是序列特异性DNA结合蛋白，并表明每个结合共识具有独特的功能，表明特异性的机制。此外，我们发现，具有更多相似氨基酸序列的蛋白质具有更多相似的结合序列。我们还发现AGL2在体外作为二聚体与DNA结合，并确定了足以进行DNA结合和二聚化的AGL2区域。最后，我们发现，几种植物MADS结构域蛋白可以结合到DNA作为同源二聚体或异源二聚体，这表明不同的监管机构的数量可能远远大于MADS盒基因的数量。
MADS domain proteins are members of a highly conserved family found in all eukaryotes. Genetic studies clearly indicate that many plant MADS domain proteins have different regulatory functions in flower development, yet they share a highly conserved DNA binding domain and can bind to very similar sequences. How, then, can these MADS box genes confer their specific functions? Here, we describe results from DNA binding studies of AGL1 and AGL2 (for AGAMOUS-like), two Arabidopsis MADS domain proteins that are preferentially expressed in flowers, We demonstrate that both proteins are sequence-specific DNA binding proteins and show that each binding consensus has distinct features, suggesting a mechanism for specificity. In addition, we show that the proteins with more similar amino acid sequences have more similar binding sequences. We also found that AGL2 binds to DNA in vitro as a dimer and determined the region of AGL2 that is sufficient for DNA binding and dimerization. Finally, we show that several plant MADS domain proteins can bind to DNA either as homodimers or as heterodimers, suggesting that the number of different regulators could be much greater than the number of MADS box genes.