Plants have to interpret temperature fluctuations over timescales ranging from hours to months to align their growth and development with the seasons. Much is known about how plants respond to temperature but the mechanisms that allow them to measure the temperature signal are less well understood.
In this study which appears in Nature, researchers Yusheng Zhao and Rea Antoniou-Kourounioti in the groups of Professor Dame Caroline Dean and Professor Martin Howard at John Innes Centre show that slow growth is used as a signal to sense long-term changes in temperature. “We have found a new temperature sensing mechanism that holds a long-term memory of the cold, integrating over fluctuating temperatures to measure cold duration. This is a new type of physical mechanism for temperature-sensing and can guide further studies in this area” explains first author Dr Yusheng Zhao.
Using a forward genetic screen – looking at the genetics of plants showing a particular trait – they found a dysfunctional response. These plants showed high levels of a protein called VIN3 in warm temperatures. This protein is well known as being upregulated during periods of cold and interacts with the epigenetic molecular memory system that allows plants to remember cold. Dr Yusheng Zhao found these plants had one of two versions of mutated NTL8, a transcription factor or regulator protein that activated VIN3 even without cold.
Read more at The John Innes Centre