Transcriptome analysis of isoxaben-induced loss of cell wall integrity in Arabidopsis nia1/2 mutant. Transcriptome analysis of isoxaben-induced loss of cell wall integrity in Arabidopsis nia1/2 mutant

Plant cell walls maintain their functional integrity during growth, defense and turgor generation through a dedicated cell wall integrity (CWI) maintenance mechanism. Upon detection of integrity impairment due to cell wall damage (CWD) compensatory responses are activated to maintain CWI. Responses include production of salicylic acid (SA), jasmonic acid (JA) and lignin as well as growth inhibition. Here we investigated the processes responsible for inducing growth inhibition upon CWD in Arabidopsis thaliana seedlings. Genetic studies implicated NITRATE REDUCTASE1 2 (NIA1 2) in the response to CWD. RNAseq-based transcriptomics showed that nearly all the CWD-induced transcript changes detectable in Col-0 were absent in nia1 2 seedlings. Overall design: Both genotypes (Col-0 and nia1/2) were treated with either isoxaben or DMSO (mock). Three replicates of Col-0 samples and two replicates of nia1/2 samples were analyzed.

植物细胞壁可通过专属的细胞壁完整性（cell wall integrity, CWI）维持机制，在生长、防御及膨压形成过程中维持其功能完整性。当检测到由细胞壁损伤（cell wall damage, CWD）引发的完整性受损时，补偿应答会被激活以维持细胞壁完整性。此类应答包括水杨酸（salicylic acid, SA）、茉莉酸（jasmonic acid, JA）及木质素的合成，以及生长抑制。本研究以拟南芥（Arabidopsis thaliana）幼苗为材料，探究了细胞壁损伤（CWD）诱导生长抑制的相关调控过程。遗传学研究表明，硝酸还原酶1/2（NITRATE REDUCTASE1/2, NIA1/2）参与了细胞壁损伤应答。基于RNA测序（RNAseq）的转录组学分析显示，在Col-0生态型拟南芥中可检测到的几乎所有细胞壁损伤诱导的转录本变化，在nia1/2幼苗中均未出现。实验设计概况：两种基因型（Col-0与nia1/2）分别用异恶草胺（isoxaben）或二甲基亚砜（DMSO，空白对照）处理。本研究共分析了Col-0样本的3次生物学重复，以及nia1/2样本的2次生物学重复。