Gommers Charlotte M M, Ruiz-Sola María Águila, Ayats Alba, Pereira Lara, Pujol Marta, Monte Elena
Plant Development and Signal Transduction Program, Center for Research in Agricultural Genomics (CSIC- IRTA-UAB-UB), Barcelona, Spain.
Laboratory of Plant Physiology, Wageningen University & Research, Wageningen, The Netherlands.
Plant Physiol. 2021 Feb 25;185(1):67-76. doi: 10.1093/plphys/kiaa015.
When germinating in the light, Arabidopsis (Arabidopsis thaliana) seedlings undergo photomorphogenic development, characterized by short hypocotyls, greening, and expanded cotyledons. Stressed chloroplasts emit retrograde signals to the nucleus that induce developmental responses and repress photomorphogenesis. The nuclear targets of these retrograde signals are not yet fully known. Here, we show that lincomycin-treated seedlings (which lack developed chloroplasts) show strong phenotypic similarities to seedlings treated with ethylene (ET) precursor 1-aminocyclopropane-1-carboxylic acid, as both signals inhibit cotyledon separation in the light. We show that the lincomycin-induced phenotype partly requires a functioning ET signaling pathway, but could not detect increased ET emissions in response to the lincomycin treatment. The two treatments show overlap in upregulated gene transcripts, downstream of transcription factors ETHYLENE INSENSITIVE3 and EIN3-LIKE1. The induction of the ET signaling pathway is triggered by an unknown retrograde signal acting independently of GENOMES UNCOUPLED1. Our data show how two apparently different stress responses converge to optimize photomorphogenesis.
在光照下发芽时，拟南芥幼苗会经历光形态建成发育，其特征为下胚轴短、叶片变绿以及子叶展开。受到胁迫的叶绿体向细胞核发出逆向信号，诱导发育反应并抑制光形态建成。这些逆向信号的核靶点尚未完全明确。在此，我们表明，用林可霉素处理的幼苗（缺乏发育成熟的叶绿体）与用乙烯（ET）前体1-氨基环丙烷-1-羧酸处理的幼苗表现出强烈的表型相似性，因为这两种信号都能在光照下抑制子叶分离。我们发现，林可霉素诱导的表型部分需要正常运作的ET信号通路，但未检测到因林可霉素处理而导致的ET排放增加。这两种处理在转录因子乙烯不敏感3（ETHYLENE INSENSITIVE3）和乙烯不敏感3样蛋白1（EIN3-LIKE1）下游的上调基因转录本中存在重叠。ET信号通路的诱导是由一种独立于解偶联基因组1（GENOMES UNCOUPLED1）的未知逆向信号触发的。我们的数据表明了两种明显不同的应激反应如何汇聚以优化光形态建成。
