RNA aptamers selected against DNA polymerase beta inhibit the polymerase activities of DNA polymerases beta and kappa.

DNA polymerase beta (polbeta), a member of the X family of DNA polymerases, is the major polymerase in the base excision repair pathway. Using in vitro selection, we obtained RNA aptamers for polbeta from a variable pool of 8 x 10(12) individual RNA sequences containing 30 random nucleotides. A total of 60 individual clones selected after seven rounds were screened for the ability to inhibit polbeta activity.

SSCP screening of individual aptamers.

Aptamers are specific binding nucleic acids that emerge from in vitro selection. During the systematic evolution of ligands by exponential enrichment (SELEX) procedure, analysis of the sequences of the numerous selected individual molecules becomes an important step in the final stage of aptamer selection. The sequencing of cloned aptamers from the selected pool generally reveals groups of identical sequences and rarely occurring individual aptamers.

[The use of nested polymerase chain reaction method for rapid detection of cytomegalovirus in peripheral blood leukocytes of patients after bone marrow transplantation].

Nested polymerase chain reaction was used for rapid detection of human cytomegalovirus in blood samples of patients subjected to bone marrow transplantation. Use of the four-primer system appreciably improved the sensitivity and specificity of the method and helped eliminate the difficulties arising in the detection of various viral strains with the minor nucleotide substitutes in the DNA template. The proposed method is a reliable tool for the early diagnosis of cytomegaloviral viremia and for monitoring the efficacy of antiviral therapy.

[Selection of primers and their use in the polymerase chain reaction for diagnosing infections caused by herpes simplex virus and cytomegalovirus].

The authors present the results of studies on the construction of highly sensitive primers for rapid diagnosis of infections caused by Herpes simplex virus (HSV) and cytomegalovirus. An oligonucleotide primer to HSV-1 is described, which permits detection of HSV-1 DNA in infected cultures and in clinical material in dilution 10(-7), whereas the "universal" primer constructed on the basis of published data detects both HSV-1 and HSV-2 only in dilution 10(-4). Study of the clinical material in polymerase chain reaction (PCR) vs.