Key message

GaKAN2, a member of the KANADI family, was found to be widely expressed in the cotton tissues and regulates trichome development through complex pathways.

Cotton trichomes are believed to be the defense barrier against insect pests. Cotton fiber and trichomes are single-cell epidermal extensions with shared regulatory mechanisms. Despite several studies underlying mechanism of trichome development remains elusive. The KANADI is one of the key transcription factors (TFs) family, regulating Arabidopsis trichomes growth. However, the function of KANADI genes in cotton remains unknown. In the current study genome-wide scanning, transcriptomic analysis, gene silencing, subcellular localization, and yeast two-hybrid techniques were employed to decipher the function of KANADI TFs family genes in cotton crop. A total of 7 GaKAN genes were found in the Gossypium arboreum. Transcriptomic data revealed that these genes were significantly expressed in stem and root. Moreover, GaKAN2 was widely expressed in other tissues also. Subsequently, we selected GaKAN2 to validate the function of KANADI genes. Silencing of GaKAN2 resulted in a 24.99% decrease in single-cell trichomes and an 11.33% reduction in internodal distance, indicating its potential role in regulating trichomes and plant growth. RNA-Seq analysis elucidated that GaSuS and GaERS were the downstream genes of GaKAN2. The transcriptional activation and similarity in silencing phenotype between GaKAN2 and GaERS suggested that GaKAN2 regulates trichomes development through GaERS. Moreover, KEGG analysis revealed that a significant number of genes were enriched in the biosynthesis of secondary metabolites and plant hormone signal transduction pathways, thereby suggesting that GaKAN2 regulates the stem trichomes and plant growth. The GFP subcellular localization and yeast transcriptional activation analysis elucidated that GaKAN2 was located in the nucleus and capable of regulating the transcription of downstream genes. This study elucidated the function and characteristics of the KANADI gene family in cotton, providing a fundamental basis for further research on GaKAN2 gene in cotton plant trichomes and plant developmental processes.

中文翻译：

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GaKAN2 是一种 KANADI 转录因子，可调节树木的茎毛

关键信息

GaKAN2是KANADI家族的成员，被发现在棉花组织中广泛表达，并通过复杂的途径调节毛状体的发育。

棉花毛状体被认为是抵御害虫的防御屏障。棉纤维和毛状体是具有共同调节机制的单细胞表皮延伸。尽管进行了多项研究，毛状体发育的潜在机制仍然难以捉摸。KANADI 是关键转录因子 (TF) 家族之一，调节拟南芥毛状体的生长。然而， KANADI基因在棉花中的功能仍不清楚。在当前的研究中，采用全基因组扫描、转录组分析、基因沉默、亚细胞定位和酵母双杂交技术来破译棉花作物中KANADI TFs家族基因的功能。在树木棉中总共发现了7个GaKAN基因。转录组数据显示这些基因在茎和根中显着表达。此外，GaKAN2在其他组织中也广泛表达。随后，我们选择GaKAN2来验证KANADI基因的功能。GaKAN2的沉默导致单细胞毛状体减少24.99%，节间距离减少11.33%，表明其在调节毛状体和植物生长方面的潜在作用。RNA-Seq分析表明GaSuS和GaERS是GaKAN2的下游基因。GaKAN2和GaERS之间的转录激活和沉默表型的相似性表明GaKAN2通过GaERS调节毛状体的发育。此外，KEGG分析显示，大量基因富集于次生代谢物的生物合成和植物激素信号转导途径，从而表明GaKAN2调节茎毛和植物生长。GFP亚细胞定位和酵母转录激活分析表明GaKAN2位于细胞核内，能够调控下游基因的转录。本研究阐明了棉花KANADI基因家族的功能和特性，为进一步研究GaKAN2基因在棉花植株毛状体和植物发育过程中的作用提供了基础基础。