Organization and distribution pattern of MGLR-3, a novel retrotransposon in the rice blast fungus Magnaporthe grisea.
A specific telomere was deleted in spontaneous, gain-of-virulence mutants derived from a rice pathogen of Magnaporthe grisea. Three different types of transposons, including Pot2, Mg-SINE, and a novel, 6-kb-long LTR (long terminal repeat)-type retrotransposon designated MGLR-3, were identified on this chromosomal end. The 114-bp-long telomeric repeat is immediately followed by the 3' LTR of MGLR-3. A truncated copy of Pot2 immediately flanks the 5' LTR, suggesting that this telomere was generated by a transposition event of MGLR-3 into this Pot2 element, causing the breakage of a chromosome. The subsequent addition of a telomeric repeat to the 3' LTR of MGLR-3 most probably repaired the broken end of the chromosome. Mg-SINE is located 25 bp away from the truncated Pot2 element. MGLR-3 exhibited strong homology to various gypsy-class retrotransposons, including grh and MAGGY in M. grisea. MGLR-3 is ubiquitous regardless of the host of origin.
Kang
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Department of Plant Pathology, The Pennsylvania State University, 311 Buckhout Laboratory, University Park, Pennsylvania 16802, USA.
D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D004271:DNA, Fungal / Q000235:genetics*; D014644:Genetic Variation; D008969:Molecular Sequence Data; D012275:Oryza / Q000382:microbiology; D010802:Phylogeny; D018626:Retroelements / Q000235:genetics*; D020079:Terminal Repeat Sequences
D004271:DNA, Fungal; D018626:Retroelements