Cloning Of CaM Gene From Caraya Illinoensis And Its Expression Under Salt Stress

Camlodulin (CaM) is a multifunctional Ca2+-binding protein in eukaryotic cells. It playsimportant roles in regulating the growth and development environment adaptation and stresstolerance in plants. Based on the CaM gene sequences in other species, we cloned on CaM genefrom Caraya illinoensis, and studied the relative expression of CaM gene by using real-timequantitative PCR technology under salt stress. The main conclusions of this study were asfollowing:1. In this study, we compared the quality of total RNA extraction by six methods. A properRNA extraction method was established for analyzing the plant growth and developmentmechanism at gene level. Efficiency of modified CTAB method was testified by2kinds ofmaterials of2species of Caraya illinoensis.2.Using RT-PCR technology, a458bp internal fragment was cloned in Caraya illinoensis,named CiCaM. Bioinformatics analysis of the gene revealed that its ORF was450bp andencoded for a polypeptide of149amino acids. Homology analysis between CiCaM genesequence and the corresponding genes of other plants showed that they have a high homology.The deduced amino acid sequence in Caraya illinoensis somatic embryos was97%homologouswith CaM in other plants reported in GenBank, this structural similarity suggested that theyhave similar function.3.β-Actin gene was used as the control for CaM gene expression analysis. Expressionanalysis by real-time quantitative PCR technology showed that CiCaM gene was expressed inleaves,young leaves and young stems. The expression leavel of CiCaM gene was higher inleaves than that in young leaves, and lowest in young stems under nature condition. With thesalt stress being heavier, the CiCaM gene was firstly increased and then decreased in leaves. Itshowed a trend of decreased but slightly increased in young leaves.But in young stems,it wasfirstly decreased and then increased and finaly decreased. The expression pattern of CiCaMgene was different in leaves, young leaves and young stems under salt stress, suggesting itsinvolvement in general response to abiotic stresses in Caraya illinoensis.