Chloroplast retrograde signaling and regulation of rice seedling development

Resumen del póster presentado al Congreso 'At the Forefront of Plant Research', celebrado en Barcelona (España) del 6 al 8 de mayo de 2019.Retrograde signaling from chloroplast to nucleus has been reported to be critical to adjust chloroplast biogenesisand modulate growth and development in Arabidopsis. GENOMES UNCOUPLED 1 (GUN1), a chloroplast-localized pentatricopeptide-repeatprotein, integrates multiple signals derived from plastid and takes an importantrole in retrograde signaling communication. Furthermore, GUN1-mediated retrograde signaling pathwaysregulate early seedling photomorphogenesis under excessive light condition by suppressing GOLDEN2-LIKE 1(GLK1) expression. In contrast, whether chloroplast retrograde signaling regulates seedling photomorphogenesis in monocotyledonsis less studied. In rice, many pentatricopeptiderepeatproteins have been found to be required for chloroplast development, seedling growth and abiotic stress response. In addition, OsGLK1 has been described to regulatechloroplast development under the control of light and phytohormones. These results suggest that GUN and GLK may regulate chloroplast development by a mechanism conserved in Oryza sativaand Arabidopsis. Our experimental system and recent data on the role of retrograde signaling in light-regulated rice developmentwill be discussed