Basic leucine zipper motif (bZIP) transcription factors (TFs) are involved in plant growth regulation, development, and environmental stress responses. These genes have been well characterized in model plants. In current study, a genome-wide analysis of bZIP genes was performed in Gossypium raimondii and Gossypium arboreum taking Arabidopsis thaliana as a reference genome. In total, 85 members of G. raimondii and 87 members of G. arboreum were identified and designated as GrbZIPs and GabZIPs respectively. Phylogenetic analysis clustered bZIP genes into 11 subgroups (A, B, C, D, F, G, H, I, S and X). Gene structure analysis to find the intro-exon structures revealed 1–14 exons in both species. The maximum number of introns were present in subgroup G and D while genes in subgroup S were intron-less except GrbZIP78, which is a unique characteristic as compared to other groups. Results of motif analysis predicted that all three species share a common bZIP motif. A detailed comparison of bZIPs gene distribution on chromosomes has shown a diverse arrangement of genes in both cotton species. Moreover, the functional similarity with orthologs was also predicted. The findings of this study revealed close similarity in gene structure of both cotton species and diversity in gene distribution on chromosomes. This study supports the divergence of both species from the common ancestor and later diversity in gene distribution on chromosomes due to evolutionary changes. Additionally, this work will facilitate the functional characterization of bZIP genes in cotton. Outcomes of this study represent foundation research on the bZIP TFs family in cotton and as a reference for other crops.

中文翻译：

---

全基因组比较分析在G. arboreum和G. raimondii（当今棉花的二倍体祖先）中的bZIP转录因子。

基本的亮氨酸拉链基序（bZIP）转录因子（TFs）参与植物生长调节，发育和环境胁迫响应。这些基因已在模型植物中很好地表征。在当前的研究中，以拟南芥为参照基因组，在雷蒙德氏棉和植物棉中进行了bZIP基因的全基因组分析。总共85件G.雷蒙德氏棉和87名成员树棉被确定，并分别命名为GrbZIPs和GabZIPs。系统发育分析聚类bZIP基因分为11个亚组（A，B，C，D，F，G，H，I，S和X）。基因结构分析发现外显子的结构揭示了两个物种中的1-14个外显子。G和D子组中存在最多的内含子，而S子组中的基因除GrbZIP78以外无内含子，这是与其他组相比的独特特征。基序分析的结果预测，所有这三个物种共享一个共同的bZIP基序。bZIP的详细比较染色体上的基因分布显示出两种棉花中基因的不同排列。此外，还预测了与直系同源物的功能相似性。这项研究的发现揭示了棉种的基因结构和染色体上基因分布的多样性非常相似。这项研究支持两种物种从共同祖先的分化以及后来由于进化变化而在染色体上的基因分布的多样性。此外，这项工作将有助于棉花中bZIP基因的功能表征。这项研究的成果代表了棉花中bZIP TFs家族的基础研究，并为其他作物提供了参考。