Variation in Copy Number of Ty3/Gypsy Centromeric Retrotransposons in the Genomes of Thinopyrum intermedium and Its Diploid Progenitors.
Speciation and allopolyploidization in cereals may be accompanied by dramatic changes in abundance of centromeric repeated transposable elements. Here we demonstrate that the reverse transcriptase part of Ty3/gypsy centromeric retrotransposon (RT-CR) is highly conservative in the segmental hexaploid Thinopyrum intermedium (JrJvsSt) and its possible diploid progenitors Th. bessarabicum (Jb), Pseudoroegneria spicata (St) and Dasypyrum villosum (V) but the abundance of the repeats varied to a large extent. Fluorescence in situ hybridization (FISH) showed hybridization signals in centromeric region of all chromosomes in the studied species, although the intensity of the signals drastically differed. In Th. intermedium, the strongest signal of RT-CR probe was detected on the chromosomes of Jv, intermediate on Jr and faint on Js and St subgenome suggesting different abundance of RT-CR on the individual chromosomes rather than the sequence specificity of RT-CRs of the subgenomes. RT-CR quantification using real-time PCR revealed that its content per genome in Th. bessarabicum is ~ 2 times and P. spicata is ~ 1,5 times higher than in genome of D. villosum. The possible burst of Ty3/gypsy centromeric retrotransposon in Th. intermedium during allopolyploidization and its role in proper mitotic and meiotic chromosome behavior in a nascent allopolyploid is discussed.
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Mikhail G
MG
Divashuk
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Thi Mai L
TM
Khuat
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Pavel Yu
PY
Kroupin
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Ilya V
IV
Kirov
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Dmitry V
DV
Romanov
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Anna V
AV
Kiseleva
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Ludmila I
LI
Khrustaleva
Federal Research and Clinical Centre of Physical-Chemical Medicine (FRCC PCM), Moscow, Russia.
Dmitry G
DG
Alexeev
Federal Research and Clinical Centre of Physical-Chemical Medicine (FRCC PCM), Moscow, Russia.
Alexandr S
AS
Zelenin
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Marina V
MV
Klimushina
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Olga V
OV
Razumova
Centre for Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Timiryazevskaya St. 49, 127550, Moscow, Russia.
Gennady I
GI
Karlov
D002503:Centromere / Q000235:genetics*; D004171:Diploidy; D018628:Gene Dosage; D018745:Genome, Plant; D017404:In Situ Hybridization, Fluorescence; D010802:Phylogeny; D006109:Poaceae / Q000235:genetics*; D018626:Retroelements
D018626:Retroelements