RESUMO
We compared the SSCP behaviour of the DNA fragments containing c-ki-ras 2 wild type 12 and 13 codons or each of the 12 possible point mutated sequences in these two codons. We found that a single electrophoresis condition was sufficient to distinguish each specific mutation from the other 11 and from the wild type sequence. This observation makes it possible to identify each specific mutation directly by SSCP without any need for reamplification and sequencing.
Assuntos
Códon , Neoplasias Colorretais/genética , Genes ras , Mutação , Polimorfismo Conformacional de Fita Simples , Proteínas Proto-Oncogênicas p21(ras)/genética , Carcinoma/genética , Clonagem Molecular , DNA de Neoplasias/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Frequência do Gene , HumanosRESUMO
Streptomyces venezuelae ATCC 10595 harbors seven rRNA gene clusters which can be distinguished by BglII digestion. The three rRNA genes present in each set are closely linked with the general structure 16S-23S-5S. We cloned rrnA and sequenced the 16S-23S spacer region and the region downstream of the 5S rRNA gene. No tRNA gene was found in these regions.