Backbone-free transformation of barrel medic (Medicago truncatula) with a Medicago-derived transfer DNA.
In the present work, Agrobacterium tumefaciens-mediated genetic transformation of the model legume Medicago truncatula Gaertn. (barrel medic) was carried out using the pSIM843 vector that contains a Medicago-derived transfer DNA, delineated by a 25-bp sequence homologous to bacterial T-DNA borders. The transfer DNA contains an expression cassette for the nptII (neomycin phosphotransferase) gene and is flanked by an expression cassette for the backbone integration marker gene ipt (isopentenyl transferase). Our results demonstrate that the Medicago-derived RB-like elements efficiently support DNA mobilization from A. tumefaciens to M. truncatula. Kanamycin-resistant shoots with normal phenotype and ipt-shooty lines were recovered at a frequency of 11.7 and 7.8%, respectively. Polymerase chain reaction (PCR) analyses demonstrated that 44.4% of the independent transgenic lines were backbone-free and evidenced the occurrence of backbone-transfer events.
Confalonieri
Massimo
M
C.R.A.-Centro di Ricerca per le Produzioni Foraggere e Lattiero-Casearie, viale Piacenza 29, 26900, Lodi, Italy.
Borghetti
Roberto
R
Macovei
Anca
A
Testoni
Claudia
C
Carbonera
Daniela
D
Fevereiro
Manuel Pedro Salema
MP
Rommens
Caius
C
Swords
Kathy
K
Piano
Efisio
E
Balestrazzi
Alma
A
D016960:Agrobacterium tumefaciens / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D046913:Medicago truncatula / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics; D010957:Plasmids; D014170:Transformation, Genetic
D004269:DNA, Bacterial; D018744:DNA, Plant; C036483:T-DNA