Sequence Characterization and Expression Analysis of Three APETALA2-like Genes from Saffron Crocus

Abstract

To further understand flowering and flower organs formation in the monocot crop saffron crocus (Crocus sativus L.), we cloned three APETALA2-like cDNA sequences of the AP2/ERF transcription factor family designated CsatAP2a/b/c as well as the respective promoter region sequences. Bioinformatics analysis with putative orthologous sequences from various plant species suggested that all three cDNA sequences encode for AP2-like proteins with the AP2 characteristic motifs and amino acids. Phylogenetically, the isolated sequences were closest to the AP2-like genes from Pisum sativum, Arabidopsis thaliana and Oryza sativa. Expression analysis indicated that the isolated C. sativus sequences were expressed in all the examined organs. Expression of CsatAP2a/b/c cDNAs was also compared in wild-type and mutant C. sativus flowers lacking stamens or carpels. Sequence analysis of the promoter revealed the presence of putative binding motifis for CCAAT, AP2 and LEAFY transcription factors indicative of regulation by developmental signals.