[Visualization of RNA transcripts with atomic force microscopy]

RNA transcripts after transcription elongation with T7 RNA polymerase in vitro were visualized by using atomic force microscopy (AFM). Fragment of pGEMEX linear DNA with the length of 1414 nucleotide pairs carrying promoter and terminator of bacteriophage T7 was used as DNA template for transcription. Immobilized on the mica (AFM substrate) RNA transcripts formed rod-like condensed structures with the length of 122 +/- 10 nm and characteristic aspect ratio ca. 4.5-5. Problems of RNA immobilization onto mica for subsequent visualization by AFM are discussed.