The AP2/ERF transcription factor family plays an important role in different biological processes such as growth, development and response to abiotic and biotic stresses in plants. The genome-wide analysis identified 531 AP2/ERF genes in Brassica napus (oilseed rape or canola) that ranged from 333 to 6440 bp in genomic and 273–2493 bp in coding DNA sequence length. We classified BnAP2/ERF proteins into five subfamilies including AP2 (58 genes), ERF (250 genes), DREB/CBF (194 genes), RAV (26 genes), and Soloist (3 genes). Furthermore, AP2/ERF proteins were subdivided into 15 groups according to the AP2/ERF classification in Arabidopsis. The number of exons in BnAP2/ERF genes was from one to eleven and most of these genes in the same subfamily had the same exon–intron pattern. The results also indicated that the composition of conserved motifs in most proteins in each group was similar. The intron–exon patterns and the composition of conserved motifs validated the BnAP2/ERF transcription factors phylogenetic classification. Based on the results of genome distribution, BnAP2/ERF genes were located unevenly on the 19 B. napus chromosomes. The results indicated that gene duplication may play an important role in genome expansion of B. napus. Furthermore, genome evolution of B. napus using orthologous and paralogous identification was studied. We found 278, 380 and 366 orthologous gene pairs between B. napus with A. thaliana, B. rapa and B. oleracea, respectively. The results of this study will be useful in investigation of functional role and molecular mechanisms of BnAP2/ERF transcription factors genes in response to different stresses.

中文翻译：

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甘蓝型油菜AP2 / ERF转录因子家族的全基因组分析。

AP2 / ERF转录因子家族在不同的生物学过程（例如植物的生长，发育以及对非生物和生物胁迫的响应）中起着重要作用。全基因组分析确定了甘蓝型油菜（油菜或油菜）中的531个AP2 / ERF基因，其基因组范围为333至6440 bp，编码DNA序列长度为273-2493 bp。我们将BnAP2 / ERF蛋白分为五个亚家族，包括AP2（58个基因），ERF（250个基因），DREB / CBF（194个基因），RAV（26个基因）和Soloist（3个基因）。此外，根据拟南芥中的AP2 / ERF分类，将AP2 / ERF蛋白分为15组。BnAP2 / ERF中的外显子数基因从1到11，并且在同一亚科中的大多数基因具有相同的外显子-内含子模式。结果还表明，每组大多数蛋白质中保守基序的组成相似。内含子-外显子模式和保守基序的组成验证了BnAP2 / ERF转录因子的系统发育分类。根据基因组分布的结果，BnAP2 / ERF基因在19个甘蓝型油菜染色体上的位置不均匀。结果表明，基因复制可能在甘蓝型油菜的基因组扩展中发挥重要作用。此外，利用直系同源和旁系同源鉴定研究了甘蓝型油菜的基因组进化。我们发现之间有278、380和366个直系同源基因对B. napus分别与拟南芥，B。rapa和B. oleracea。这项研究的结果将有助于调查BnAP2 / ERF转录因子基因响应不同压力的功能作用和分子机制。