Donald T M, Leach C R, Clough A, Timmis J N
Department of Genetics, University of Adelaide, South Australia.
Heredity (Edinb). 1995 May;74 ( Pt 5):556-61. doi: 10.1038/hdy.1995.77.
Fluorescence in situ hybridization (FISH) with biotinylated rDNA revealed the presence of an rRNA gene cluster on both the A and B chromosomes of Brachycome dichromosomatica, an Australian native ephemeral plant of the arid regions of south-eastern Australia. This species contains only two pairs of A chromosomes and up to three B chromosomes. The regular attachment of the B chromosome to a nucleolus suggests that these ribosomal RNA genes are transcribed. Southern hybridization of DNA from 0B and +B plants digested with a variety of restriction enzymes indicates that the rRNA genes on the A and B chromosomes are the same in sequence and methylation status.
