Authors: Rim Ghedira Sylvie De Buck Frédéric Van Ex Geert Angenon Ann Depicker
Publish Date: 2013/08/24
Volume: 238, Issue: 6, Pages: 1025-1037
Abstract
TDNA transfer and integration frequencies during Agrobacteriummediated root explant cocultivation and floral dip transformations of Arabidopsis thaliana were analyzed with and without selection for transformationcompetent cells Based on the presence or absence of CRE recombinase activity without or with the CRE TDNA being integrated transient expression versus stable transformation was differentiated During root explant cocultivation continuous light enhanced the number of plant cells competent for interaction with Agrobacterium and thus the number of transient gene expression events However in transformation competent plant cells continuous light did not further enhance cotransfer or cointegration frequencies Upon selection for root transformants expressing a first TDNA 43–69 of these transformants showed cotransfer of another nonselected TDNA in two different light regimes However integration of the nonselected cotransferred TDNA occurred only in 19–46 of these transformants indicating that TDNA integration in regenerating root cells limits the transformation frequencies After floral dip transformation transient TDNA expression without integration could not be detected while stable TDNA transformation occurred in 05–13 of the T1 seedlings Upon selection for floral dip transformants with a first TDNA 8–34 of the transformants showed cotransfer of the other nonselected TDNA and in 93–100 of them the TDNA was also integrated Therefore a productive interaction between the agrobacteria and the female gametophyte rather than the TDNA integration process restricts the floral dip transformation frequenciesWe thank Karolina Komorowska Anni Jacobs Marion Naudts and Jonah Nolf for practical assistance Marnik Vuylsteke for statistical analysis and Martine De Cock and Annick Bleys for help in preparing the manuscript This work was supported by grants from the Flemish Community and the Research Foundation Flanders G021106 FVE was indebted to the Agency for Innovation through Science and Technology in Flanders for a predoctoral fellowship
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