Identification, Sequencing and Stability Evaluation of Eight Reference Genes in Saffron (Crocus sativus L.)

Saffron (Crocus sativus L.) is the most valuable and expensive spice in the world. The stigmas of saffron are the source of valuable apocarotenoids such as crocin, picrocrocin and safranal. transcriptomic and expression studies of genes are important steps in investigating of secondary metabolites in plants. One of the important prerequisites for such studies is the existence of reliable and stable reference genes to normalize the expression of other genes. In the present study, eight reference genes were identified and isolated using transcriptome of saffron and their expression stability was evaluated by nonparametric statistics and methods. The results of amplification and sequencing showed accurate identification of eight reference genes Actin, EF1, GAPDH, H3, MDH, TBP, UBC and UBQ. The expression stability evaluation revealed that MDH and UBQ genes had the highest stability among different saffron tissues and TBP had the lowest stability among them. In this study, for first time, eight reference genes were isolated from saffron and their expression stability was evaluated. The reference genes identified in the present study can be used as stable genes to normalize gene expression in transcriptomic and expression studies of saffron plant.