Abstract:
Root systems can display variable architectures that contribute to nutrient foraging or to increase the tolerance of abiotic stress conditions. Root tip excision promotes the developmental progression of previously specified lateral root (LR) founder cells, which allows to easily measuring the branching capacity of a given root as regards its genotype and/or growth conditions. Here, we describe the natural variation among 120 Arabidopsis thaliana accessions in root system architecture (RSA) after root tip excision. Wound-induced changes in RSA were associated with 19 genomic loci using genome-wide association mapping. Three candidate loci associated with wound-induced LR formation were investigated. Sequence variation in the hypothetical protein encoded by the At4g01090 gene affected wound-induced LR development and its loss-of-function mutants displayed a reduced number of LRs after root tip excision. Changes in a histidine phosphotransfer protein putatively involved in cytokinin signaling were significantly associated with LR number variation after root tip excision. Our results provide a better understanding of some of the genetic components involved in LR capacity variation among accessions.
摘要:
根系可以显示出可变的结构,有助于营养觅食或增加对非生物胁迫条件的耐受性。根尖切除促进先前指定的侧根(LR)建立细胞的发育进程,这允许容易地测量给定根的关于其基因型和/或生长条件的分枝能力。这里,我们描述了根尖切除后根系结构(RSA)中120个拟南芥种质之间的自然变异。使用全基因组关联作图,伤口诱导的RSA变化与19个基因组基因座相关。研究了与伤口诱导的LR形成相关的三个候选基因座。由At4g01090基因编码的假设蛋白质的序列变异影响了伤口诱导的LR发育,其功能丧失突变体在根尖切除后显示出减少的LR数量。假定参与细胞分裂素信号传导的组氨酸磷酸转移蛋白的变化与根尖切除后的LR数量变化显着相关。我们的结果使人们更好地了解了与品种之间LR容量变化有关的某些遗传成分。