JAR1 | Jasmonic acid-amido synthetase JAR1

KLH-conjugated synthetic peptide derived from Arabidopsis thaliana JAR1 protein sequence, UniProt: Q9SKE2, TAIR: At2g46370

 64 kDa (Arabidopsis thaliana)

5 µg of protein from Arabidopsis thaliana Col0 and jar1-1 mutant were extracted using basic phenol protocol. 1g were grinded with liquid nitrogen with mortair and pestle, powder were resuspended in 3 mL of protein buffer (0.5 M Tris-HCl, 0.7 M sucrose, 1 mM PMSF, 50 mM EDTA, 0.1 M KCl and 0.2% β-mercaptoethanol; pH 8.0). Homogenate were centifuged at 8000 rpm and supernatant were mixed with three volumes of basic phenol, the mixture were incubated with agitation at room temperature during 10 mins. The mixture were centrifuged at 10000 rpm at 4ºC during 30 min, phenolic phase were recuperated in new tube and were mixed with one volume of ammonium acetate 0.1M in methanol, the mixture were incubated at -20 ºC during 4 hours. The mixture were centrifuged at 10000 rpm at 4º C during 20 minutes and protein pellet were washed three times with ammonium acetate 0.1M in methanol. Finally proteins were resuspended in tris-HCl (50 mM, pH 8.0) and the protein concentration were determined according Bradford method. Samples of 5 and 10µg were separated on 15 % SDS-PAGE using tank (BioRad system) to transfer to nitrocellulose membrane during 1 hour at 400 A. Blots were blocked with skimmed milk (10%) for 1h at room temperature (RT) with agitation. Blot was incubated in the primary antibody at a dilution of 1: 1000 for 1h at RT with agitation. The antibody solution was decanted and the blot was rinsed briefly twice, then washed once for 15 min and 3 times for 5 min in TBS-T at RT with agitation. Blot was incubated in secondary antibody (anti-rabbit IgG horse radish peroxidase conjugated, from Agrisera AS09 602) diluted to 1:20 000 in for 1h at RT with agitation. The blot was washed as above and developed for 5 min with ECL according to the manufacturer's instructions. Exposure time was 30 and 60 seconds. For transference control the membrane was stained with Ponceau red and integrity of proteins was evaluated using 12% SDS-PAGE comassie blue stained.

JAR1 (Jasmonic acid-amido synthetase JAR1; jasmonate resistant 1) is catalyzing the synthesis of jasmonates-amino acid conjugates by adenylation. Plays an important role in the accumulation of JA-Ile in response to wounding, both locally and systemically; promotes JA responding genes especially in distal part of wounded plants, via the JA-Ile-stimulated degradation of JAZ repressor proteins by the SCF(COI)E3 ubiquitin-protein ligase pathway. Involved in the apoptosis-like programmed cell death (PCD) induced by fungal toxin fumonisin B1-mediated (FB1). Contributes to the sensitivity toward F.graminearum.
Alternative names: Jasmonate-amino acid synthetase JAR1, Protein FAR-RED INSENSITIVE 219, Protein JASMONATE RESISTANT 1