Molecular cloning and expression analysis of 12-oxophytodienoate reductase cDNA by wounding in Solanum tuberosum

Jasmonic acid (JA) and 12-oxophytodienoic acid (OPDA) are signal molecules involved in the stress and defense responses in plants. A full-length cDNA clon of OPR3 encoding 12- oxophytodienoate reductase 3, key enzyme involved in the biosynthesis of JA from linolenic acid was obtained from a Solanum tuberosum cDNA library. Sequence analysis showed that OPR3 encoded a polypeptide of 400 amino acids with a predicted molecular mass of 43.9 kDa and pI of 7.72. The deduced amino acid sequence of OPR3 showed high similarities to other 12-oxophytodienoate reductases. A peroxisomal signal sequence indicates OPR3 probable location in peroxisome. Levels of OPR3 mRNA accumulated in potato leaves reaching maximum levels within 1 hr of mechanical wounding. Elevated levels of JA were correlated to expression of the OPR3 gene

Callus induction and plant regeneration of Ulex europaeus

Abstract A callus induction and plant regeneration protocol was developed from leaf and thorn explants for the plant Ulex europaeus . Explants were incubated on 2% sucrose half-strength Murashige and Skoog Medium (MS) with various combinations of plant growth regulators and antioxidants. The best frequency of callus and shoot formation was obtained with 2,4-dichlorophenoxyacetic acid (2,4-D) 1 mg/l x kinetin (Kin) 0.2 mg/l (DK Medium; callus induction) and zeatin (Z) 1 mg/l (DK medium; shoot induction). Both media were supplemented with ascorbic acid 200 mg/l to prevent browning and death of the explants. The regenerated shoots transferred to rooting medium (half-strength MS Medium, 2% sucrose) showed rapid growth and development of roots (100%). Rooted plantlets were successfully transferred to soil in pots containing a 3:1 mixture of soil and vermiculite

Protective effect of an antimicrobial peptide from Mytilus edulis chilensis expressed in Nicotiana tabacum L

A "defensin-like" antibacterial peptide from Mytilus edulis chilensis, was sub-cloned into a binary vector for expression in plant tissues. The resulting new clone was electroporated into A. tumefaciens to transform tobacco plants. The presence of the construct in transgenic tobacco lines was demonstrated through RT-PCR, Northern and Western blots. Transformed positive plants were selected and grown for challenging. Tobacco leaves were infiltrated with Pseudomonassyringae pv. syringae and visual lesions determined at different times post-exposure. Of seven plants exposed, four gave variable protection up to seven days post-infection while one of them appears to be fully protected. These results suggest that defensin-like antimicrobial peptides from molluscs are a good source to provide resistance of tobacco plants to Pseudomonassyringae pv. syringae