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Published on: January 20, 2023
Tm1: a mutator/foldback transposable element family in root-knot nematodes
Stephen M Gross1, Valerie M Williamson
1Department of Nematology, University of California Davis, Davis, California, United States of America.
Plos One
|September 21, 2011
Summary
A novel transposable element family, Tm1 (Transposon in Meloidogyne-1), has been identified in root-knot nematodes. These elements may explain how asexual nematodes acquire virulence, impacting crop pathogens.
Area of Science:
- Genetics
- Molecular Biology
- Nematology
Background:
- Root-knot nematodes (Meloidogyne incognita-group) are significant asexual crop pathogens.
- These nematodes exhibit heritable changes in virulence despite lacking sexual reproduction.
- Understanding the genetic mechanisms behind virulence evolution in asexual nematodes is crucial.
Purpose of the Study:
- To characterize a novel transposable element family, Tm1 (Transposon in Meloidogyne-1), in root-knot nematodes.
- To investigate the role of Tm1 elements in the genetic diversity and virulence of asexual Meloidogyne species.
- To compare Tm1 elements in asexual M. incognita-group species with the sexual M. hapla.
Main Methods:
- Comparative genomics and sequence analysis of Meloidogyne species.
- Identification and characterization of transposable elements, specifically Tm1.
- Analysis of gene deletions and their association with virulence in M. javanica.
Main Results:
- A novel transposable element family, Tm1, was identified, characterized by composite terminal inverted repeats.
- Tm1 elements in M. incognita include histone-hairpin motif elements, MITE-like elements, and those encoding a putative transposase.
- The Cg-1 gene, implicated in virulence, was found to be within a Tm1 element.
- M. hapla possesses Tm1 elements but lacks histone hairpin motifs and intact transposase-encoding elements.
Conclusions:
- Tm1 elements represent a novel class of transposable elements in root-knot nematodes.
- These elements may contribute to genome evolution and the acquisition of virulence in asexual Meloidogyne species.
- The presence and variation of Tm1 elements highlight potential mechanisms for genetic adaptation in these important plant pathogens.
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