Li Chunping, Zhao Jieyin, Liu Zhongshan, Yang Yanlong, Lai Chengxia, Ma Jun, Aierxi Alifu
Research Institute of Economic Crops, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China.
Engineering Research Centre of Cotton, Ministry of Education/College of Agriculture, Xinjiang Agricultural University, 311 Nongda East Road, Urumqi 830052, China.
Plants (Basel). 2024 Apr 17;13(8):1127. doi: 10.3390/plants13081127.
Cotton is the most widely planted fiber crop in the world, and improving cotton fiber quality has long been a research hotspot. The development of cotton fibers is a complex process that includes four consecutive and overlapping stages, and although many studies on cotton fiber development have been reported, most of the studies have been based on cultivars that are promoted in production or based on lines that are used in breeding. Here, we report a phenotypic evaluation of based on immature fiber mutant () and wild-type (Xin W 139) lines and a comparative transcriptomic study at seven time points during fiber development. The results of the two-year study showed that the fiber length, fiber strength, single-boll weight and lint percentage of were significantly lower than those of Xin W 139, and there were no significant differences in the other traits. Principal component analysis (PCA) and cluster analysis of the RNA-sequencing (RNA-seq) data revealed that these seven time points could be clearly divided into three different groups corresponding to the initiation, elongation and secondary cell wall (SCW) synthesis stages of fiber development, and the differences in fiber development between the two lines were mainly due to developmental differences after twenty days post anthesis (DPA). Differential expression analysis revealed a total of 5131 unique differentially expressed genes (DEGs), including 290 transcription factors (TFs), between the 2 lines. These DEGs were divided into five clusters. Each cluster functional category was annotated based on the KEGG database, and different clusters could describe different stages of fiber development. In addition, we constructed a gene regulatory network by weighted correlation network analysis (WGCNA) and identified 15 key genes that determined the differences in fiber development between the 2 lines. We also screened seven candidate genes related to cotton fiber development through comparative sequence analysis and qRT-PCR; these genes included three TFs ( (bHLH), (Dof), and (C3H)). These results provide a theoretical basis for obtaining an in-depth understanding of the molecular mechanism of cotton fiber development and provide new genetic resources for cotton fiber research.
棉花是世界上种植最广泛的纤维作物，提高棉花纤维品质长期以来一直是研究热点。棉纤维的发育是一个复杂的过程，包括四个连续且重叠的阶段，尽管已经报道了许多关于棉纤维发育的研究，但大多数研究是基于生产中推广的品种或育种中使用的品系。在此，我们报告了基于未成熟纤维突变体（）和野生型（新W139）品系的表型评价以及纤维发育过程中七个时间点的比较转录组学研究。两年的研究结果表明，的纤维长度、纤维强度、单铃重和衣分均显著低于新W139，其他性状无显著差异。对RNA测序（RNA-seq）数据进行主成分分析（PCA）和聚类分析表明，这七个时间点可清晰地分为三个不同的组，分别对应纤维发育的起始、伸长和次生细胞壁（SCW）合成阶段，两个品系之间纤维发育的差异主要源于开花后20天（DPA）后的发育差异。差异表达分析显示，两个品系之间共有5131个独特的差异表达基因（DEG），包括290个转录因子（TF）。这些DEG被分为五个簇。基于KEGG数据库对每个簇的功能类别进行注释，不同的簇可以描述纤维发育的不同阶段。此外，我们通过加权基因共表达网络分析（WGCNA）构建了一个基因调控网络，并鉴定了15个决定两个品系之间纤维发育差异的关键基因。我们还通过比较序列分析和qRT-PCR筛选了七个与棉花纤维发育相关的候选基因；这些基因包括三个TF（（bHLH）、（Dof）和（C3H））。这些结果为深入了解棉花纤维发育的分子机制提供了理论基础，并为棉花纤维研究提供了新的遗传资源。
