Molecular cloning and characterization of a mitogen-activated protein kinase kinase (OoMAPKK1) in Origanum onites L. (Lamiaceae)

Plants are constantly exposed to a variety of environmental (biotic and abiotic) stresses and they develop sophisticated signaling pathways to adapt the changing environment. Mitogen activated protein kinase (MAPK) cascade in plants is a common mechanism used to translate the external stimuli into cellular responses and composed of triple kinases modules namely MAPKKK-MAPKK-MAPK. In this study, a MAPKK (OoMAPKK1) has been cloned from Origanum onites L. (Lamiaceae) which is a commercially cultivated aromatic plant in the world. The OoMAPKK1 gene is 1,059 bp long, encodes a 353 amino acid protein with an estimated molecular mass of 39.416 kDa. The secondary structure of the OoMAPKK1 protein was analyzed by SOPMA and the 3D crystal structure of OoMAPKK1 protein was created by using Cn3D 4.1 software. The expression levels of OoMAPKK1 under different abiotic stresses (cold, wounding and abscisic acid) were investigated by semi-quantitative RT-PCR. Changes in the expression of OoMAPKK1 under cold stress, wounding and abscisic acid (ABA) application may suggest that OoMAPKK1 is involved in the cross-talk of multi-environmental stress responses.