EFFECTS OF PHENOL TREATMENT ON CLOCK GENES EXPRESSION IN TOBACCO HAIRY ROOTS

SOSA ALDERETE, LG; AGOSTINI E; MEDINA MI; GUIDO M; MAS P

Cordoba

Congreso; LII Reunión Anual de SAIB 2016,; 2016

SAIB

As a consequence of changing environmental conditions, most species contain an endogenous circadian clock which allows them to daily adapt and optimize physiology and metabolism. Our main objective was to evaluate the effects of phenol treatment (PT) (100 mg/l) on expression of clock genes (CG) and putative genes involved in metabolism of xenobiotic compounds (MXC) such as peroxidase (NtPXC8), cytochrome monooxygenase (Cyp71D21), glucosyl transferase (GT) and glutathione S-transferase (GST). For this, hairy root cultures (HRC) of Nicotiana tabacum of 3 weeks synchronized by a 12:12 light dark photoperiod were used. HRC subject to PT for 24 h showed a significant decrease in patterns of CG expression (LHY, TOC1, FKF1, GI and PRR9) as compared with water treated controls. When expression profiles of putative genes for MXC were assessed, we found that PT up-regulated the expression of all genes analyzed. The highest expression of NTPXC8 and GST was observed at dark phase (ZT 19) while GT and Cyp71D21 exhibited an increased expression at ZT 19 as well as at light phase (ZT3 and ZT 11). These findings show for the first time that PT down-regulated CG expression but significantly up-regulated expression of putative MXC genes across time. These results also suggests a putative circadian control on MXC gene expression, improving our understanding of phenol metabolism in plants.