Interactions between the circadian clock genes and the metabolism of xenobiotic compounds

SOSA ALDERETE, LG; RONCHI, H; MEDINA MI; GUIDO M; AGOSTINI E

Paraná, Entre Ríos

Congreso; LIV REUNION ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACION BIOQUIMICA Y BIOLOGIA MOLECULAR (SAIB), Paraná (Entre Ríos), 5-8 de noviembre de 2018.; 2018

Plants as sessile and light-sensitive organisms have developed endogenous mechanisms such as the circadian clock (CC) that allow them anticipate daily environmental changes adjusting their physiology at the appropriate time of the day. However, the role of CC on the metabolism of xenobiotic compounds (MXC), like phenol is still few known. Therefore, the main aim of this work consists to analyze the possible circadian regulation of the expression of genes related to MXC. For this, hairy root cultures from Nicotiana tabacum of 3 week-old, synchronized by light/darkness cycles, were used. Our results showed that phenol treatment (PT) differentially affected the temporal expression profiles of most of the selected genes related to MXC. PT was able to induce, at certain times (zt), the expression of genes related to MCX in the light phase, for instance the NtCYPG8H (zt 7), NtPOD72 and NtUGTBeta genes (zt 3), as well as in the dark phase, for example NtGSTZ gene (zt 19). Moreover, PT decreased the expression of the NtCYP710 (zt 23) and NtUGT89 (Zt 7-19) genes. These results would suggest that although the genes associated to MXC conserve temporal expression profiles regulated by the CC, PT affected such regulation modifying the expression profiles of these genes either by induction or repression. Thus, phenol is able to trigger the loss of temporality in the expression of several genes. The fact that these genes related to MXC were induced or repressed by phenol, give us a key knowledge about the appropriate time of the day that the enzymes encoded by them (CytP450s, PODs, GSTs and GTs) would be more active for the removal of such environmental pollutant.