ATP-binding cassette (ABC) proteins are powerful transporters and are involved in countless cellular processes of plant development. In the present study, 315, 169, and 170 ABC genes were identified in Gossypium hirsutum, Gossypium raimondii, and Gossypium arboreum, respectively. The ABC genes were clustered into eight subfamilies based on their structural and phylogenetic features. The ABC members within the same subfamily showed similar protein structures and motif composition. Both tandem and segmental duplication events appear to have shaped the extensive expansion of the ABC transporter gene family, with purifying selection being the primary driving force for evolution. Expression profiles derived from transcriptome data exhibited distinct expression patterns of GhABC genes in various tissues and in response to different abiotic stresses. Additionally, analyses of the expression patterns of syntenic GhABC paralog pairs across 10 tissues and at ovule and fiber development stages revealed their functional conservation, subfunctionalization, neo-functionalization, and pseudogenization during evolution. Finally, the analysis of co-expressed subnetworks and tissue-specific expression profiles suggested several ABC gene members might be involved in fiber development. This research provides a comprehensive overview of the ABC transporter gene family and forms the basis for further functional analysis in cotton.

中文翻译：

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三种棉属植物 ABC 转运蛋白基因家族的全基因组比较分析

ATP 结合盒 (ABC) 蛋白是强大的转运蛋白，参与植物发育的无数细胞过程。在本研究中，在Gossypium hirsutum、Gossypium raimondii和Gossypium arboreum中鉴定出315、169和 170 个 ABC 基因， 分别。ABC 基因根据其结构和系统发育特征分为八个亚家族。同一亚科中的 ABC 成员显示出相似的蛋白质结构和基序组成。串联和节段复制事件似乎塑造了 ABC 转运蛋白基因家族的广泛扩张，纯化选择是进化的主要驱动力。源自转录组数据的表达谱在各种组织中表现出不同的 GhABC 基因表达模式，并响应不同的非生物胁迫。此外，对跨 10 个组织以及在胚珠和纤维发育阶段的同线 GhABC 旁系同源对的表达模式的分析揭示了它们在进化过程中的功能保守、亚功能化、新功能化和假基因化。最后，对共表达子网络和组织特异性表达谱的分析表明，几个 ABC 基因成员可能参与了纤​​维发育。这项研究提供了 ABC 转运蛋白基因家族的全面概述，并为棉花的进一步功能分析奠定了基础。