TY  - EJOU
AU  - Jin, Yue 
AU  - Tang, Xiaoying 
AU  - Wei, Bingke 
AU  - Zhi, Lulu 
AU  - Mao, Yan 
AU  - Pedro, García-Caparrós 
AU  - Hu, Xiangyang 

TI  - A Transcriptional Suppressor NTL8 Interacts with CONSTANS to Control Photoperiod-Mediated Flowering Time in <i>Arabidopsis thaliana</i>
T2  - Phyton-International Journal of Experimental Botany

PY  - 2026
VL  - 95
IS  - 3
SN  - 1851-5657

AB  - Plants perceive rhythmic photoperiodic signals to modulate flowering time. In <i>Arabidopsis thaliana</i>, long-day light conditions accelerate flowering through CONSTANS (CO)-activated FLOWERING LOCUS T (FT) signal pathway. The CO protein abundance presents circadian oscillation, enabling precise regulation of <i>FT</i> transcription. NTL8 belongs to the NAC transcription factor family and is reported to control leaf trichome development. Here, we reported that NTL8 regulated flowering time in Arabidopsis, because overexpressing <i>NTL8</i> significantly delayed flowering time, whereas loss-of-function mutant of <i>NTL8</i> accelerated flowering time. <i>NTL8</i> also presented circadian expression, maintaining elevated transcript levels during the daytime. Biochemical and genetic analyses revealed that NTL8 physically interacted with CO <i>in planta</i>, thereby antagonizing CO activity and repressing <i>FT</i> expression to delay the flowering time. Furthermore, overexpressing <i>NTL8</i> reduced the protein stability of CO, particularly by attenuating CO accumulation in the morning time and promoting CO degradation during the night. Collectively, our findings indicated that NTL8 delayed photoperiod-dependent flowering time by suppressing CO-mediated activation of <i>FT</i> expression and destabilizing CO protein. This study uncovers a previously unrecognized role for NTL8 in coordinating circadian and photoperiodic signals to fine-tune flowering time in <i>Arabidopsis thaliana</i>.
KW  - Arabidopsis; NTL8; CONSTANS; flowering time

DO  - 10.32604/phyton.2026.067796