Peach PpZAT12 and Arabidopsis AtZAT12 ortholog transcription factors have conserved molecular roles

GISMONDI M.; GABILONDO J.; BUDDE C. O.; LARA M. V.; DRINCOVICH M. F.; BUSTAMANTE C. A.

Paraná

Congreso; LIV Reunión de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2018

SAIB

Cold storage (CS) is needed to prevent the rapid decay of peaches at ambient temperature. However, low temperature can generate chilling injury (CI), a group of physiological disorders which severely affects fruit quality. Many post-harvest approaches were developed to prevent CI, being heat treatment (HT) a proven efficient strategy. C2H2 transcription factor-encoding PpZAT12 was HT- and CS-induced in CI-tolerant cultivars, as A. thaliana AtZAT12. Both 35S::AtZAT12 and 35S::PpZAT12/KO-AtZAT12 A. thaliana transgenic lines showed impaired growth and development, rendering smaller plants (compared to Col-0) with flowering time delay, curved leaves and down-pointing siliques. Known targets of AtZAT12 were assessed by RT-qPCR and a label-free proteomic approach was performed on adult leaves, finding many molecules commonly modified in gain-of-function genotypes. These results suggest that ZAT12 orthologs could have similar molecular mechanisms to in vivo regulate phytohormones metabolism, stress responses, RNA processing, retrograde signaling and photosynthesis. In silico analyses of putative targets not only pointed out their relationship with observed phenotypes but also with temperature stress protection. Moreover, their fruit orthologs present conserved temperature-driven expression. Overall, ZAT12 orthologs have similar genomic features, temperature sensitivity and molecular mechanisms to allow plant cells to tolerate undesired agronomic disorders, such as CI.