Advances in Light Signaling Transduction Research in China

doi:10.11983/CBB16150

Abstract

Abstract: Light is one of the most important environmental factors that affect various processes of plant growth and development, including seed germination, photomorphogenesis, shade avoidance, flowering and senescence. Since the 1980s, by using the model plant Arabidopsis thaliana, plant biologists have achieved many significant progresses in the area of light regulation of plant growth and development. A series of photoreceptors and protein factors have been identified and the light signaling regulatory networks have been primarily established. Chinese scientists have made significant contributions to this area. In this review, we summarize the major advancements in light signaling transduction by Chinese researchers during the past decade and propose some future directions in this field.

Yanjun Jing, Rongcheng Lin. Advances in Light Signaling Transduction Research in China[J]. Chinese Bulletin of Botany, 2017, 52(3): 257-270.

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URL: https://www.chinbullbotany.com/EN/10.11983/CBB16150

https://www.chinbullbotany.com/EN/Y2017/V52/I3/257

Figures/Tables 2

Figure 1 Simplified overview of the signal transduction pathway mediated by phytochrome, crypotochrome and UVR8 There are 2 mechanisms of transcriptional regulation by PHY and CRY. These two photoreceptors mediated light inhibition by COP1 degradation of transcription factor HY5, HFR1, LAF1 and CO etc. In addition, PHY and CRY interact with PIFs and/or CIBs which are enriched on the DNA sequence to directly modulate expression of light response genes (LRBs). In UVR8-mediated signal transduction pathway, the COP1 complex induced by UV-B contains UVR8 and promotes light signaling by stabilizing HY5. COP1 interacts with PHY, CRY and UVR8, but the molecular mechanism of these interactions seems to be different. For example, the interactions lead to ubiquitination and degradation of CRY2 and PHYA, but it seems not to affect the stability of PHYB, CRY1 and UVR8. Both CRY1 and CRY2 interact directly with SPA1 in blue light dependent manner, but the molecular outputs may be different. CRY1-SPA1 competitively inhibits COP1-SPA1 interaction, CRY2-SPA1 seems to enhance CRY2-COP1 interaction. In both cases COP1 activity is inhibited. Arrows indicate positive regulation and bars indicate negative regulation.

Figure 2 Photoreceptors and potential light signaling intermediates The key regulators have been identified to regulate light-response genes at various levels, including transcriptional, posttranscriptional, translational, and posttranslational regulation. The light signaling pathway cross-talks with exogenous environmental signaling and internal phytohormone signaling to shape various developmental responses.

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