On May 31st, Research paper entitled "Thetranscription factor FcWRKY40 of Fortunellacrassifolia functions positively in salt tolerance through modulation ofion homeostasis and proline biosynthesis by directly regulating SOS2 and P5CS1 homologues", authored by the citrus anti-adversity teamof key laboratory of Education Ministry for horticultural plant biology, was published in the New Phytologistonline. The corresponding author of the paper is Prof. Liu Jihong, the first author is Dai Wenshan, a doctoral student.
Transcriptional regulation is an essential molecular mechanism of plant stress response. Constructing a transcriptional regulatory network and identifying transcription factors involved in this network have important theoretical significance for elucidating plant stress responses, and lay the foundation for finding key genes that can be used for the improvement of stress resistance.  In this study, physiological tests, genetic transformation, and molecular biochemical analysis were used to illuminate the salt resistance of the transcription factor FcWRKY40, and its mechanism was confirmed to act directly on two target genes, FcSOS2 and FcP5CS1, thereby maintaining ion balance and regulating proline synthesis to participate in stress response. Through the study, a complete salt stress response pathway (i.e., ABA-ABF2-WKY40-SOS2/P5CS1) was established, and the molecular regulation network of proline accumulation in plants under abiotic stress was revealed and provided strong evidence for the the establishment of integrated regulatory networks of hormonessynthesis, signal transduction, and metabolite accumulation under stress conditions.
In recent years, Prof. Liu Jihong has achieved a number of innovative research results in the field of transcriptional regulation of stress response in citrus and its related plants. Previously, the team analyzed the molecular mechanism of polyamine accumulation under abiotic stress and identified the first transcription factor that negatively regulates polyamine synthesis (Plant Physiology, 2016; Journal of Experimental Botany, 2011a, 2011b, 2015a, 2015b, 2018; Plant Cell Environment, 2015); the transcriptional regulatory networks that regulate antioxidant enzymes and glucose metabolism genes in response to stress response (Plant Physiology, 2013; Plant Cell Environment, 2014) was expounded. Through research, the theoretical understanding of the transcriptional regulation of plant stress responses has been enriched.

Translated by Dou Jieni