ISSN:
1615-6110
Keywords:
Angiosperms
;
Brassicaceae
;
Matthiola incana.—DNA interspersion pattern
;
Messenger RNA
;
RNA complexity
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The DNA of the cruciferMatthiola incana (Brassicaceae, Capparales) has been investigated for the pattern of sequence interspersion and RNA transcription. A short period pattern of interspersion (Xenopus-like interspersion pattern) is predominant (60%). Similar to a series of other Angiosperms (tobacco, soybean, parsley and some cereals) repetitive clusters orinter-se interspersion patterns of repetitive DNA occur inMatthiola genome and amount to 12%. From the hybridization of single copy DNA with poly(A)−-RNA and from cDNA/poly(A)+-RNA and cDNA/poly(A)−-RNA hybridizations a number of about 9,400 active genes can be estimated forM. incana seedlings. Both RNA constituents (poly(A)+-RNA and poly(A)−-RNA) contain mainly the same protein-coding mRNA sequences. Total mRNA is amounting to about 4% of theM. incana RNA population. A total of 1.2% (or about 30% of mRNA) of theM. incana RNA is represented by polyadenylated mRNA sequences. About 3.6% of single copy DNA hybridizes with poly(A)−-RNA. Approximately 7% of theM. incana genome, organized in a short period pattern of DNA sequence interspersion, is transcribed into RNA sequences (mRNA). About 6% of clustered repetitive DNA is expressed into RNA sequences such as rRNA and tRNA. Approximately 1.6 × 106 rRNA, 1.75 × 107 tRNA and 3.7 × 105 mRNA molecules are present perMatthiola seedling cell. The transcription rate of single rRNA and tRNA genes can be estimated to be about 1,400 or 1,100 copies per gene, respectively.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02409898
