Transcriptome Analysis of Diurnal and Nocturnal-Warmed Plants, the Molecular Mechanism Underlying Cold Deacclimation Response in Deschampsia antarctica

• Published in: International Journal of Molecular Sciences
• Main Authors: Dariel López, Giovanni Larama, Patricia L. Sáez, León A. Bravo
• Format: Text
• Language: English
• Published: Multidisciplinary Digital Publishing Institute 2023
• Subjects: Antarctic plant; asymmetric warming; CBF; climate change; cold deacclimation; gene expression; RNA-seq; Antarctic; The Antarctic; Antarctic Peninsula; Antarc*; Antarctica
• Online Access: https://doi.org/10.3390/ijms241311211

Warming in the Antarctic Peninsula is one of the fastest on earth, and is predicted to become more asymmetric in the near future. Warming has already favored the growth and reproduction of Antarctic plant species, leading to a decrease in their freezing tolerance (deacclimation). Evidence regarding the effects of diurnal and nocturnal warming on freezing tolerance-related gene expression in D. antarctica is negligible. We hypothesized that freezing tolerance-related gene (such as CBF-regulon) expression is reduced mainly by nocturnal warming rather than diurnal temperature changes in D. antarctica. The present work aimed to determine the effects of diurnal and nocturnal warming on cold deacclimation and its associated gene expression in D. antarctica, under laboratory conditions. Fully cold-acclimated plants (8 °C/0 °C), with 16h/8h thermoperiod and photoperiod duration, were assigned to four treatments for 14 days: one control (8 °C/0 °C) and three with different warming conditions (diurnal (14 °C/0 °C), nocturnal (8 °C/6 °C), and diurnal-nocturnal (14 °C/6 °C). RNA-seq was performed and differential gene expression was analyzed. Nocturnal warming significantly down-regulated the CBF transcription factors expression and associated cold stress response genes and up-regulated photosynthetic and growth promotion genes. Consequently, nocturnal warming has a greater effect than diurnal warming on the cold deacclimation process in D. antarctica. The eco-physiological implications are discussed.