Trimethylguanosine Synthase1 (TGS1) Is Essential for Chilling Tolerance.

Chilling stress is a major factor limiting plant development and crop productivity. Because the plant response to chilling is so complex, we are far from understanding the genes important in the response to chilling. To identify new genes important in chilling tolerance, we conducted a novel mutant screen, combining a confirmed SALK T-DNA insertion collection with traditional forward genetics. We screened a pool of more than 3700 confirmed homozygous SALK T-DNA insertion lines for visible defects under prolonged growth at 5°C. Of the chilling-sensitive mutants we observed, mutations at one locus were characterized in detail. This gene, At1g45231, encodes an Arabidopsis (