Plant dehydrin proteins (DHNs) are known to be important for environmental stress tolerance and are involved in various developmental processes. Two full
length cDNAs JcDHN
1 and JcDHN
2 encoding two dehydrins from Jatropha cur
cas seeds were identified and characterized. JcDHN
1 is 764 bp long and contains an open reading frame of 528 bp. The deduced JcDHN
1 protein has 175 a.a. residues that form a 19.3
kDa polypeptide with a predicted isoelectric point (pI) of 6.41. JcDHN
2 is 855 bp long and contains an open reading frame of 441 bp. The deduced JcDHN
2 protein has 156 a.a. residues that form a 17.1
kDa polypeptide with a predicted pI of 7.09. JcDHN
1 is classified as type Y3SK2 and JcDHN
2 is classified as type Y2SK2 according to the YSK shorthand for structural classification of dehydrins. Homology analysis indi
cates that both JcDHN
1 and JcDHN
2 share identity with DHNs of other plants. Analysis of the conserved domain revealed that JcDHN
2 has glycoside hydrolase GH20 super
family activity. Quantitative real time PCR analysis for JcDHN
1 and JcDHN
2 expression during seed development showed increasing gene expression of both their transcript levels along with the natural dehydration process during seed development. A sharp increase in JcDHN
2 transcript level occurred in response to water content dropping from 42% in mature seeds to 12% in dry seeds. These results indicate that both JcDHNs have the potential to play a role in cell protection during dehydration occurring naturally during jatropha orthodox seed development.