Characterization of cold responsive uncoupling protein1 (UCP1) gene from Brassica juncea L. (Czern. and Coss.)

Mitochondrial uncoupling protein1 (UCP1) is indicative of alleviating oxidative stress in plants. Brassica juncea is a predominantly grown oilseed crop on the Indian subcontinent. Owing to its socio-economic importance and chances of yield losses due to climatic vulnerability, we cloned and characterized UCP1 gene from this plant species. An open reading frame of 918 bp of BjUCP1 cDNA encoding a polypeptide of 305 amino acids was obtained. Two BjUCP1 genomic sequences of 1964 and 1924 bp were cloned and both comprised of nine exons and eight introns. Bioinformatics analysis of deduced protein revealed the presence of three ETPS sequences along with UCP specific signature sequences and plant specific motifs in BjUCP1. Phylogenetic analysis revealed low rate of evolution and high conservation when compared with UCP1 from other organisms. Conservation of amino acid residues crucial for the functioning of the protein was observed. Ubiquitous expression was perceived by RT-qPCR in various plant tissues with especially high transcript levels in inflorescence tissue. BjUCP1 was found to be responsive to cold treatment at 72 h time point. It is suggested that UCP1 might be involved in controlling ROS levels during vital developmental stages and towards acclimatization to cold temperature.