ISSN:
1617-4623
Keywords:
Key wordsTc1-mariner
;
Filamentous fungi
;
Fusarium oxysporum
;
Transposase
;
Evolution
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The transposable element impala is a member of the widespread superfamily of Tc1-mariner transposons, identified in the genome of the plant pathogenic fungus Fusarium oxysporum. This element is present in a low copy number and is actively transposed in the F.␣oxysporum strain F24 that is pathogenic for melons. The structure of the impala family was investigated by cloning and sequencing all the genomic copies. The analysis revealed that this family is composed of full-length and truncated copies. Four copies contained a long open reading frame that could potentially encode a transposase of 340 amino acids. The presence of conserved functional domains (a nuclear localisation signal, a catalytic DDE domain and a DNA-binding domain) suggests that these four copies may be autonomous elements. Sequence comparisons and phylogenetic analysis of the impala copies defined three subfamilies, which differ by a high level of nucleotide polymorphism (around 20%). The coexistence of these divergent subfamilies in the same genome may indicate that the impala family is of ancient origin and/or that it arose by successive horizontal transmission events.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004380050822
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