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Published on: September 11, 2017
DNA Fingerprint Probe from Mycosphaerella graminicola Identifies an Active Transposable Element
Phytopathology
|October 24, 2008
Summary
Researchers identified a transposable element in Mycosphaerella graminicola, the wheat pathogen. This element likely causes DNA fingerprint variations observed during both sexual and asexual reproduction.
Area of Science:
- * Molecular Biology
- * Mycology
- * Plant Pathology
Background:
- * DNA fingerprinting is widely used to study Mycosphaerella graminicola, the pathogen causing Septoria tritici blotch in wheat.
- * Previous studies assumed that transposable elements caused the observed DNA fingerprint polymorphism, but direct evidence was lacking.
Purpose of the Study:
- * To investigate the hypothesis that transposable elements are responsible for DNA fingerprint polymorphism in Mycosphaerella graminicola.
- * To characterize the DNA fingerprint probe pSTL70 and determine its role in generating polymorphic patterns.
Main Methods:
- * Sequencing of the DNA fingerprint probe pSTL70 and related clones.
- * Southern blot analyses to assess the contribution of different sequence elements to fingerprint patterns.
- * Analysis of progeny from sexual crosses and asexual reproduction to observe changes in DNA fingerprint bands.
Main Results:
- * Probe pSTL70 contains sequences characteristic of transposable elements, including reverse transcriptase and direct repeats.
- * Both repeat and reverse-transcriptase sequences partially replicated the DNA fingerprint pattern.
- * New DNA fingerprint bands appeared in progeny from sexual crosses, indicating activity during meiosis.
- * Gains or losses of DNA fingerprint bands were observed in asexual lines, suggesting activity during asexual reproduction.
- * Probe pSTL70 showed specificity for Mycosphaerella graminicola, not hybridizing with related fungi.
Conclusions:
- * The DNA fingerprint probe pSTL70 likely identifies a transposable element in Mycosphaerella graminicola.
- * This transposable element appears to be active during both sexual and asexual reproduction, contributing to population diversity.
- * The element may have been recently acquired and is specific to Mycosphaerella graminicola.
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