ISSN:
1617-4623
Keywords:
Transposable element
;
Retrotransposon
;
Reverse transcriptase
;
Rice
;
Polymerase chain reaction
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Three families of retrotransposons of rice (Tos1,Tos2, andTos3) were isolated by using a method based on the sequence conservation of the primer binding site for reverse transcription. This method should be generally applicable for cloning retrotransposons of other plants. One retrotransposon,Tos3-1, was studied in detail.Tos3-1 is 5.2 kb long, has structures common to retrotransposons, such as long terminal repeats (LTR), a primer binding site complementary to the initiator tRNA, a polypurine tract, and generates target sequence duplications flanking the inserted element. Southern blotting analysis showed that sequences homologous toTosl, 2 and3 are found in wild rice species as well as in cultivated rice species, but not in maize and tobacco. The copy number and genomic location of the families vary in different strains of one species of wild rice, suggesting that these elements may still be active. Retrotransposons were also screened for by amplification of the reverse transcriptase coding region using the polymerase chain reaction (PCR). At least two types of copia-like elements (Tos4] andTos5) were found. The total copy number of retrotransposons in the rice genome was estimated to be about 1000. These results suggest that, as inDrosophila, retrotransposons are the major transposon class in rice.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00587581
Permalink
