Title : The switch from skotomorphosgenesis to photomorphogenesis triggers the regulatory transition of miRNA biogenesis in Arabidopsis thaliana
Abstract:
Light signaling pathways are central to the development and growth of plants. The pathways render plants to perceive the discrete wavelength, intensity, and duration of light, by which information of light can be transmitted and coordinated, resulting in intricate physiological and developmental responses. Extensive studies on the light-triggered switch from skotomorphosgenesis to photomorphogenesis have elucidated many important biochemical entities in light signaling pathways. However, the studies have mostly focused on photoreceptors, signaling intermediates and their proteolytic repression by negative regulators. Recently, we found that the core components of miRNA processing - Dicer-like 1 (DCL1), SERRATE (SE) and HYPONASTIC LEAVES 1 (HYL1) - are differentially expressed by the light-induced developmental transition. The core processing proteins are constitutively degraded by unknown proteolytic pathways in etiolated seedlings but dramatically stabilized in de-etiolated seedlings. In contrasts to the up-regulated microprocessor components, the levels of miRNAs are notably diminished by light. Based on
