Abstract
ABSTRACT:
Dehydrins have a key role in protecting plants, especially in the grey mangrove tree Avicennia marina (Forssk.) Vierh. from salt stress. Understanding the mangrove plants at the molecular level will be necessary for developing such highly salt-tolerant crops. The full-length cDNA of the DHN gene sequence AmDHN was isolated from Avicennia marina and contained a 588bp open reading frame (ORF) encoding a 195 amino acid protein with a molecular weight of about 19.746k Da. As well as, multiple alignment sequences and phylogenetic relationships were analyzed for sequences using MEGA7 software revealing that AmDHN has a high identity with other DHNs plants and suggesting that AmDHN belongs to group II (LEA) proteins. Using bioinformatics analysis tools, we have investigated characterize and gene expression to better understand the structure and function analysis prediction of the AmDHN protein. AmDHN protein contains motifs (SYK2), Sn, Yn segment, and at least one copy of a lysine-rich conserved sequence known as K-segment (consensus EKKGIME/DKIKEKLPG) near the C terminal, the 3D predicted the structure protein sequence of the secondary structure, the top 5 final models using by I-TASSER server and several parameters computed by the software were obtained. Our results indicate that the AmDHN gene plays an essential role in salt stress remediation in the Avicennia marina. They could be used for further studies to understand the molecular mechanisms of salinity tolerance in plants and can be potentially utilized in transforming other plants to improve tolerance to salinity stress.

Key words: Keywords: Mangrove (Avicennia marina), AmDHN, salt tolerance genes, quantitative real-time PCR.