An extrachromosomal fragment of telomeric DNA in wheat.
A procedure developed originally for selective extraction of viral (extrachromosomal) DNA from virus-infected mammalian cells was applied to cell nuclei isolated from uninfected wheat embryos. The resulting nuclear extrachromosomal DNA (exDNA) was enriched for telomere-type sequences by isopycnic centrifugation and inserted into the Sma I site of pUC119. A cloned DNA fragment (241 bp) was found to consist primarily of tandemly repeated heptamere units of the same sequence (5'-CCCTAAA-3') that is known to predominate in telomeric DNA of Arabidopsis thaliana. Hybridization experiments indicate that extrachromosomal telomeric repeats are abundant in resting embryos and disappear rapidly during germination.
Bucholc
M
M
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw.
Buchowicz
J
J
D017360:Arabidopsis / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D018744:DNA, Plant / Q000032:analysis / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D012639:Seeds / Q000737:chemistry; D016615:Telomere / Q000235:genetics*; D014908:Triticum / Q000235:genetics*
D018744:DNA, Plant