RESUMEN
Oligonucleotides representing 60 trinucleotide (21mers) and four dinucleotide (20mers) tandem repeats were directly synthesized and arrayed onto an aminated polypropylene substrate. DNA samples of different complexities (a CAG-containing 21mer oligonucleotide, PCR fragments of 200 to 3,000 bp, and cosmids with 31 to 35 kb inserts) were radiolabelled and hybridized to the oligonucleotide array at various temperatures. When compared to sequence data available from the test DNAs, the reverse blot system specifically identified various tri- and dinucleotide short tandem repeats (STRs) in every case. Moreover, there was no random or cross hybridization to nonspecific sequences. It was possible to detect as few as three repeated units in a particular location, as shown for (CCT)n, (GCC)n and (CAC)n triplets in cosmid DNA. Varying the hybridization stringency can enhance the detection of STRs. This single-step reverse blot system therefore allows the rapid, specific and sensitive identification of various STRs in DNA sources of different complexity.
Asunto(s)
Secuencias Repetitivas de Ácidos Nucleicos , Secuencia de Bases , Clonación Molecular , ADN/análisis , Técnicas Genéticas , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Reacción en Cadena de la PolimerasaRESUMEN
We have modified polypropylene to serve as a new solid-phase support for oligonucleotide synthesis. The plastic is first surface aminated by exposure to an ammonia plasma generated by radiofrequency plasma discharge. The aminated polypropylene has been found to be useful as a support for the in situ synthesis of oligonucleotides from monomers. Furthermore, oligonucleotides synthesized on the surface of the plastic remain attached following deprotection and can be used directly for hybridization.
Asunto(s)
Oligonucleótidos/síntesis química , Polipropilenos , Secuencia de Bases , Fibrosis Quística/genética , ADN/síntesis química , ADN Complementario/síntesis química , Exones , Humanos , Yodo , Datos de Secuencia Molecular , Mutación , Hibridación de Ácido Nucleico , Oligonucleótidos/genética , Compuestos Organofosforados , Oxidación-ReducciónRESUMEN
The synthesis, chemical stability and anti-tumor activity of pyrazine diazohydroxide, sodium salt, a compound that has been selected for development to clinical trials, are described. The compound shows a half-life of about 100 minutes at pH 7.4 and is active against a number of experimental tumors.