MUTANTS FOR GENES INVOLVED IN THE 5?-3? mRNA DECAY PATHWAY HAVE ALTER CIRCADIAN PHENOTYPES

MORA-GARCIA, S; CARENO, DA; PEREZ SANTANGELO, S.; YANOVSKY MJ.

Buenos Aires

Congreso; Reunión Conjunta de Sociedad de Biociencia.; 2017

Circadian rhythms allow organisms to adjust biological processes to occur at the most appropriate time of day. They are controlled by a complex gene network ?called the central oscillator?, in which genes interact mainly by transcriptional feedback loops, keeping an approximate 24h rhythm. Recent evidence supports the importance of post-transcriptional regulation as a key step for the correct oscillation of the clock. Among the different post-transcriptional mechanisms, in this work we focus on RNA stability and decay using the plant model organism, Arabidopsis thaliana. We studied the 5?-3? messenger RNA (mRNA) decay pathway. This includes genes encoding proteins involved in different steps of the pathway, from translation arrest, to mRNA degradation, including poly(A) tail shortening and decapping. We characterize different outputs of the clock in mutants for genes involved in this pathway. All the mutants showed a longer period of leaf movement, a late flowering time, and no appreciable change in the hypocotyl elongation. Also, we observed a deregulation of mRNA levels from some core oscillator genes. This are the first steps to understand how mRNA degradation contributes to the fine-tuning of circadian rhythms. Further mechanistic studies will be done to achieve a deeper comprehension of this regulatory layer.