AtTRAF: A novel RNA chaperone involved in temperature stress responses in Arabidopsis

STROLOGO L.; GISMONDI M.; GABILONDO J.; BUDDE C.; LARA M. V.; DRINCOVICH M. F.; BUSTAMANTE, C. A.

Córdoba

Congreso; LII Reunión de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2016

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

Once harvested, peaches are cold-stored in order to delay ripening. However, refrigeration can produce chilling injury (CI) symptoms, affecting the quality of fruits. Among others strategies, heat treatment (HT) preceding cold storage resulted effective in preventing CI symptoms. PpTRAF is a HT- and cold-induced transcript that encodes a TRAF-type Zn finger with a confirmed RNA chaperone role in peach fruit. In this work, we studied AtTRAF: the A. thaliana uncharacterized PpTRAF protein ortholog. Using an in vivo complementation test in E. coli RL211 strain, the RNA helicase activity of AtTRAF was confirmed. The promotor region of this gene was analyzed and several stress-related cis elements were found. To study AtTRAF mRNA abundance, we measured its expression levels by RT-qPCR in different organs and conditions. AtTRAF was found in several tissues, reaching the highest mRNA levels in flowers, and showed inductions after both low and high temperatures. AtTRAF KO mutants and lines overexpressing the gene were obtained and analyzed regarding their ability to germinate and elongate the roots under cold and heat stresses, as well as in the presence of ABA, NaCl, H2O2 or mannitol. Several growth differences were addressed in comparison to wild-type lines. Overall, these results suggest that AtTRAF could have a molecular role as RNA chaperone under cold and heat stress in A. thaliana.