Plastids are a subset of organelles, including chloroplast, chromoplast, etioplast etc., which harbor photosynthesis and the biosynthesis of many primary and secondary metabolites. Retrograde signals are emitted by organelles to regulate nuclear gene expression. Plastid retrograde signals mediated by GENOMES UNCOULED (GUN) genes play vital roles in chloroplast biogenesis and in response to environmental stimuli.

      On 11^th January 2021, Dr. Guo-Zhang Wu from School of Agriculture and Biology, Shanghai Jiao Tong University (SJTU) and Prof. Ralph Bock from Max Planck Institute of Molecular Plant Physiology (MPIMP) jointly published a review paper on Plant Cell titled “GUN control in retrograde signaling: How GENOMES UNCOUPLED proteins adjust nuclear gene expression to plastid biogenesis”. In this review paper, the authors summarized the recent advances and future perspectives in the field of plastid retrograde signaling, with focusing on retrograde signaling mediated by GUN genes, and their role in plastid biogenesis, stress response and the crosstalk with light signaling.

      In this review article, the authors first discussed the mechanism of GUN retrograde signaling, and gave perspective comments on the key questions in the field. Then the GUN1 gene, the central node of multiple retrograde signaling pathways, was discussed with the empathizes on its role in maintenance of plastid protein homeostasis under stress conditions. Follow up, the role of HSP90 chaperone complex in retrograde signaling was discussed in detail. At the last part, the authors focused on the crosstalk of retrograde signaling and light signaling, and the biogenesis of other type of plastids.

      Dr. Guo-Zhang Wu from SJTU and Prof. Ralph Bock from MPIMP are co-corresponding authors, meanwhile Dr. Wu is the first author. Dr. Wu joint School of Agriculture and Biology in 2019 as a tenure-track associate professor and a group leader. He established the Max Planck Partner Group of “Organelle and Stress Biology” in SJTU which is financed by Max Planck Society. This research has been supported by grants from the National Natural Science Foundation of China (NSFC; 32070299), the Shanghai Pujiang Program (20PJ1405600) to Guo-Zhang Wu, and the Max Planck Society and grants from the Deutsche Forschungsgemeinschaft (FOR 804, BO1482/15-2, SFB-TR 175) to Ralph Bock.

Article link: https://academic.oup.com/plcell/article/33/3/457/6080804

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