title: Transgenic poplars: expression of chimeric genes using four different constructs.
abstract: Leaf or stem explants of a hybrid poplar clone (Populus tremula X Populus alba), sensitive to Agrobacterium tumefaciens, were co-cultivated either by an octopine or a nopaline disarmed A. tumefaciens modified strain. Transformed poplar shoots were readily regenerated from explants. The protocol was improved using the nopaline disarmed strain C58/pMP90 with the binary vector pBI121. This protocol was then used to test three other vectors. The first one, possessing a nptII gene fused to the CaMV 19S promoter, permitted regeneration of transformed shoots in presence of 50 to 100 mg/l kanamycin. The two other vectors carried an additional nptII gene under the control of the CaMV 35S or CaMV 35S promoter with a double enhancer sequence (CaMV 70). CaMV 70 promoter provided consistently higher level of gene expression than the other promoters in both callus and leaf tissues.
authors.affiliation: Station d'Amélioration des Arbres Forestiers, Institut National de la Recherche Agronomique, F-45160, Ardon, Olivet, France.
authors.forename: J C
authors.initials: JC
authors.lastname: Leple
authors.forename: A C
authors.initials: AC
authors.lastname: Brasileiro
authors.forename: M F
authors.initials: MF
authors.lastname: Michel
authors.forename: F
authors.initials: F
authors.lastname: Delmotte
authors.forename: L
authors.initials: L
authors.lastname: Jouanin