Over-expression of heat shock factor gene (AtHsfA1d) from Arabidopsis thaliana confers formaldehyde tolerance in tobacco

Formaldehyde (HCHO) is a major indoor air pollutant. Plants can be used to remove HCHO from polluted air because they can use HCHO as a carbon source to incorporate it into one-carbon (C1) metabolism. However, high concentrations of exogenous HCHO cause damages to plants. Therefore, genetic engineering is an effective measure to improve ability of plants to clear the HCHO pollution. Expression of AtHsfA1d encoding heat shock transcription factor of Arabidopsis was induced by HCHO stress. AtHsfA1d was cloned into the pYES3 vector and transformed into Saccharomyces cerevisiae. Yeast cells expression of AtHSFA1d showed higher tolerance to HCHO stress than wild-type (WT) cells. AtHsfA1d was introduced into tobacco and the expression of AtHSFA1d in transgenic lines was demonstrated using Western blot analysis. Transgenic tobacco showed higher uptake rate to aqueous HCHO, had the higher biomass and produced higher content of total proteins than WT plants. These results indicated that AtHsfA1d conferred HCHO tolerance to yeast and tobacco. AtHsfA1d is a good candidate to develop phytoremediation plants for HCHO pollution.