Abstract:

The endoplasmic reticulum 18∶1 fatty acid desaturase (FAD2) is to provide 18∶2 fatty acid required for the correct assembly of cellular membranes throughout the plant. In this study, a full-length cDNA clone of PtFAD2 gene (GenBank accession number: DQ316788) was firstly isolated using the in silico cloning method in Populus tomentosa. It is 1 276 bp in length and the open reading frame encodes a peptide of 388 amino acids, which match the known peptide sequences. The predicted amino acid sequence shows significant homology with those of other plant species, which contain typical domains owned by FAD2 proteins. The transcripts of PtFAD2 are equal in leaves, stem and roots using semi-quantitative RT-PCR. When the shoots were experienced the cold treatments, the transcripts of PtFAD2 isn't reduced in 24 h. This suggests that the PtFAD2 may be a structural expression protein and it isn't induced by low temperature. This study provides the basis for not only cloning and research of poplar fatty acid desaturase gene, but also the genetic engineering of plant fatty acid in the near future.

Key words: Populus tomentosa, PtFAD2, molecular cloning, RT-PCR, expression analysis