Evolutionary divergence of the APETALA1 and CAULIFLOWER proteins
Evolutionary divergence of the APETALA1 and CAULIFLOWER proteins
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DOI：
10.1111/j.1759-6831.2012.00211.x
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发表时间：
2012-11
影响因子：
3.7
通讯作者：
Bin Wang;Ning Zhang;Chunce Guo;Guixia Xu;H. Kong;Hongyan Shan
中科院分区：
文献类型：
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作者：
Bin Wang;Ning Zhang;Chunce Guo;Guixia Xu;H. Kong;Hongyan Shan
摘要APETALA 1（AP 1）和CAULIFLOWER（CAL）是一对通过前菊科全基因组重复事件产生的旁系同源基因。AP 1和CAL都具有部分冗余和独特的功能。已有研究表明，它们蛋白质的K区和C区是功能分化所必需的。然而，这些地区的哪些差异是主要因素，以及这些差异是如何积累起来的，仍然是未知数。在本研究中，我们比较了这两种蛋白质的序列，并确定了它们之间的5个缺口和55个氨基酸替换。基因组序列的研究进一步表明，蛋白质的差异是由非同义取代和外显子-内含子结构的变化引起的。三维结构重建显示，AP 1和CAL的序列差异导致两者在α螺旋的数量、长度、位置和方向方面存在差异，特别是在K和C区。祖先蛋白与AP 1和CAL的序列和三维结构的比较表明，祖先AP 1蛋白经历了较少的变化，而祖先CAL蛋白在基因复制后不久积累了更多的变化，相对于它们的共同祖先。此后，AP 1样蛋白经历了很少的突变，而CAL样蛋白直到菊科谱系I的多样化才被保守。这表明AP 1和CAL样蛋白在基因复制后不对称进化。这些发现为AP 1和CAL基因的功能分歧提供了新的见解。
Abstract APETALA1 (AP1) and CAULIFLOWER (CAL) are a pair of paralogous genes that were generated through the pre‐Brassicaceae whole‐genome duplication event. AP1 and CAL have both partially redundant and unique functions. Previous studies have shown that the K and C regions of their proteins are essential for the functional divergence. However, which differences in these regions are the major contributors and how the differences were accumulated remain unknown. In the present study, we compared the sequences of the two proteins and identified five gaps and 55 amino acid replacements between them. Investigation of genomic sequences further indicated that the differences in the proteins were caused by non‐synonymous substitutions and changes in exon–intron structures. Reconstruction of three‐dimensional structures revealed that the sequence divergence of AP1 and CAL has resulted in differences between the two in terms of the number, length, position and orientation of α‐helices, especially in the K and C regions. Comparisons of sequences and three‐dimensional structures of ancestral proteins with AP1 and CAL suggest that the ancestral AP1 protein experienced fewer changes, whereas the ancestral CAL protein accumulated more changes shortly after gene duplication, relative to their common ancestor. Thereafter, AP1‐like proteins experienced few mutations, whereas CAL‐like proteins were not conserved until the diversification of the Brassicaceae lineage I. This indicates that AP1‐ and CAL‐like proteins evolved asymmetrically after gene duplication. These findings provide new insights into the functional divergence of AP1 and CAL genes.