Mapping quantitative trait loci for freezing tolerance in a recombinant inbred line population of A rabidopsis thaliana accessions Tenela and C24 reveals REVEILLE1 as negative regulator of cold acclimation

A recombinant inbred line population for the accessions C24 and T enela ( T e), showing large variation in freezing tolerance, was established to study genetic determinants of cold acclimation capacity in A rabidopsis thaliana . Mapping of quantitative trait loci ( QTL ) revealed three QTL regions on chromosomes 2, 4 and 5. With the aid of gene expression data, the M yb family transcription factor REVEILLE1 ( A t5g17300) on chromosome 5 was identified as a novel negative regulator of freezing tolerance in A rabidopsis. The ability to increase freezing tolerance when exposed to low temperatures is a property of many plant species from temperate climates and involves a wide array of metabolic adjustments and changes in gene expression. In A rabidopsis thaliana , natural accessions show high variation in their acclimation capacity, and freezing tolerance correlates with natural habitat temperatures. To investigate the genetic basis of this variation, a recombinant inbred line population from reciprocal crosses between the accessions C24 and T enela ( T e), showing large variation in tolerance, was established. Over 250 recombinant inbred lines were genotyped for 69 single nucleotide polymorphism markers in a linkage map with 391.9 centimorgans (cM) and phenotyped for their freezing tolerance using the electrolyte leakage method that reports cell damage after a freeze–thaw cycle. Mapping of quantitative trait loci ( QTL ) for acclimated plants revealed three QTL regions on chromosomes 2, 4 and 5. Based on gene expression data, QTL regions were screened for genes differentially responding to low temperature in C24 and T e. Among the candidate genes, the Myb family transcription factor REVEILLE1 ( At5g17300 ) on chromosome 5 was identified as a novel negative regulator of freezing tolerance in A rabidopsis .