Isolation and characterization of a harvest-induced promoter of an alfalfa gene, hi7
- 190 Downloads
A cDNA library was made by subtractive hybridization of cDNA from non-harvested and harvested alfalfa plants. One cDNA clone, hi7, in Northern blot analysis showed a high level of transcription of this gene in harvested tissue, but not in non-harvested tissue, nor in wounded or heat shock treated tissue. A 640 bp promoter region isolated by genomic walking based on hi7 cDNA sequence, was fused to a GUS gene and transferred to tobacco and Medicago truncatula. When leaf tissue from transgenic tobacco plants was harvested, incubated for 24 h at room temperature, and then stained for GUS activity, a strong blue colour was observed throughout the tissue, but not in tissue that was stained immediately following harvesting. The expression of the GUS gene was also induced in tobacco plants sprayed with abscissic acid (ABA) and in callus derived from these plants when transferred to medium containing ABA.
KeywordsHarvest-induced gene hi7 Promoter ABA Transgenic plants Alfalfa
Extensive funding for this research was provided by the Natural Sciences and Engineering Research Council of Canada, Strategic Grants Program. As well, we would like to express our appreciation to Dina Hodi for technical supports.
- Ivashuta S, Naumkina M, Gau M, Uchiyama K, Isobe S, Mizukami Y, Shimamoto Y (2002) Genotype-dependent transcriptional activation of novel repetitive elements during cold acclimation of alfalfa (Medicago sativa). Plant J31:615–627Google Scholar
- Marten GC, Buxton DR, Banes RF (1988) Feeding values (Forage quality) In: Hanson AA. Barnes DK, Hill RR Jr (eds) Alfalfa and alfalfa improvement. The American Society of Agronomy Inc, Madison, pp 463–484Google Scholar
- Sambrook J, Russell DW (2001) Molecular Cloning; a laboratory manual. Cold Spring Harbor laboratory Press, New YorkGoogle Scholar
- Trieu AT, Burleigh SH, Kardailsky IV, Maldonado-Mendoza IE, Versaw WK, Blaylock LA, Shin H, Chiou TJ, Katagi H, Dewbre GR, Weigel D, Harrison MJ (2000) Transformation of Medicago truncatula via infiltration of seedlings or flowering plants with Agrobacterium. Plant J 22:531–541PubMedCrossRefGoogle Scholar
- Zhang JY, Broeckling CD, Blancaflor EB, Sledge MK, Sumner LW, Wang ZY (2005) Overexpression of WXP1, a putative Medicago truncatula AP2 domain- containing transcription factor gene, increases cuticular wax accumulation and enhances drought tolerance in transgenic alfalfa (Medicago sativa). Plant J 42:689–707PubMedCrossRefGoogle Scholar