ISSN:
1432-0983
Keywords:
Transformation
;
Stability
;
Hygromycin B resistance
;
Rice blast fungus
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Magnaporthe grisea was transformed with cosmid pAN7-2 encoding hygromycin B resistance but containing no homology with the M. grisea genome. Rearrangement of the integrated DNA was detected in several hygromycin B-resistant progeny from cross Guy11-T10-1 (a single-copy integration site transformant)x2539 (sensitive wild-type parent), but not in hygromycin B-resistant progeny from four other crosses. Transformants produced typical lesions when inoculated onto host plants. Southern hybridization revealed rearrangements of integrated DNA in single conidial isolates of highcopy transformant 2539-T1-1 re-isolated from host plants, characterized by excision of one or more copies of the transforming plasmid. Plasmid loss and rearrangement were also observed within single conidial isolates derived from transformant 2539-T1-1 following ten asexual generations on non-selective agar medium. These examples of instability of integrated DNA in M. grisea transformants suggest that caution should be exercised in the use of transformation for assessing the phenotypic effects of specific introduced genes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00318655
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