A new molecule discovered in the battle between plants a...( from the carboxyl terminus of a 92 amin...)

from the carboxyl terminus of a 92 amino acid precursor, proAtPep1, a scenario commonly found in both animal and plant peptide precursors. No physiological role was known for AtPep1, and a function was sought in Arabidopsis by incubating plants under a variety of conditions and monitoring expression of the proAtPep1 gene. Cold and dehydration stress and exposure to ABA or MeSA did not affect the expression of proAtPep1, but wounding, exposing plants to methyl jasmonate (MeJA), or supplying plants with the AtPep1 peptide through cut petioles induced expression of the gene. Also expressed in response to AtPep1 were the PDF1.2 gene (a plant defensin) and the PR-1 gene, (a pathogenesis-related gene). Two wound-related genes, LOX2 and VSP2, were not induced by AtPep1. Supplying AtPep1 to jasmonate-deficient fad3-2 fad7-2 fad8 mutant plants did not induce the proAtPep1, PDF1.2 or PR-1 genes, indicating that AtPep1 signaling involves the octadecanoid pathway. AtPep1 induction of defense genes in excised Arabidopsis leaves was inhibited by DPI, implicating the generation of H2O2 in the signaling pathway. Constitutively overexpressing the proAtPep1 gene in Arabidopsis induced a constitutive activation of PDF1.2, PR-1, and tyrosine amino transferase (TAT3) genes, but not the expression of LOX2 or VSP2 genes. The transgenic plants were more resistant toward the oomycete root pathogen Pythium irregulare than wild-type plants, evidenced by a more robust leaf and root growth upon infection. ProAtPep1 belongs to a seven member gene family in Arabidopsis with tissue-specific paralogs that exhibit differential expression profiles. Orthologs of the proAtPep1 gene have been identified in important crop species including canola, soybean, potato, tomato, rice and poplar.

'"/>

Contact: Brian Hyps
bhyps@aspb.org
571-332-2522
American Society of Plant Biologists
19-Jul-2005

Page: 1 2
Related biology news :

1. Small molecules may explain psoriasis
2. Allergy molecule identified
3. Frog molecule could provide drug treatment for brain tumors
4. TU Delft tracks the influence of a cancer inhibitor on a single DNA molecule
5. Magnetic computer sensors may help study biomolecules
6. Hamilton College researchers discover molecules with potential to treat breast cancer
7. Early exposure to indoor fungus molecules may protect infants against future allergies
8. Minuscule molecules pack a powerful punch
9. UCLA identifies new molecule involved in the bodys processing of dietary fat
10. Penn scientists engineer small molecules to probe proteins deep inside cell membrane
11. LED array signals successful binding of drug-delivery molecules to DNA