We have isolated wound-inducible genes from soybean using suppression subtractive hybridization (SSH) method and were able to obtain the full-length clone of GmDjp1 gene encoding DnaJ-like protein. The full-length cDNA of GmDjp1 is 689 bp with an open reading frame (ORF) consisting of 163 amino acid (aa). Genomic southern blot confirmed that soybean genome has two copies of GmDjp1 gene. Northern blot analysis showed that the RNA expression of GmDjp1 gene is specifically induced by heat, NaCl, wounding and drought stresses. It was demonstrated that GmDjp1-GFP was targeted to the nucleus in tobacco cell. GmDjp1 overexpression plants showed more susceptible to salt and heat stress compared to WT. RNA expression level of Hsp18.2 and Hsp25.3-P was lower than that of WT during recovery after heat hock in plants. This indicates that GmDjp1 may play a negative regulator to stress responses in plants.

We isolated wound-inducible genes using suppression subtractive hybridization (SSH) method and were able to obtain to clone W3 gene encoding dnaJ like protein. The full-length cDNA of W3 is 689 bp with an open reading frame (ORF) consisting of 163 amino acid (aa). Genomic southern blot confirmed that soybean genome has two copies of W3 gene. Northern blot analysis was also carried out for the gene expression during heat, NaCl, drought, wounding stresses. The expression of W3 gene specifically induced by heat, NaCl, wounding and drought stress. Using GFP fusion vector, W13-GFP was targeted both to nucleus. For the functional analysis of W3, His-tagged W3 recombinant protein was heterologously expressed in E. coli. The W3 recombinant cells showed enhanced heat tolerance compared to that of vector control cells. We suggest that dnaJ-like W3 protein function as molecular chaperone in the nucleus of the plant cell during various stresses.

We isolated wound-inducible genes using suppression subtractive hybridization (SSH) method and were able to obtain to clone w123 gene encoding dnaJ like protein. The full-length cDNA of w123 is 689 bp with an open reading frame (ORF) consisting of 163 amino acid (aa). Genomic southern blot confirmed that soybean genome has two copies of w123 gene. Northern blot analysis was also carried out for the gene expression during heat, NaCl, drought, wounding stresses. The expression of w123 gene specifically induced by heat, NaCl, wounding and drought stress. Using GFP fusion vector, w123-smGFP was targeted both to nucleus. For the functional analysis of w123, His-tagged w123 recombinant protein was heterologously expressed in E. coli. The w123 recombinant cells showed enhanced heat tolerance compared to that of vector control cells. We suggest that dnaJ-like w123 protein function as molecular chaperone in the nucleus of the plant cell during various stresses.