[Comprehensive analysis of RNA expression of Mycobacterium leprae and clinical and biological significance].

Completion of Mycobacterium leprae genome sequence revealed that there are many pseudogenes and non-coding regions, but rather small numbers of protein-coding genes. This result indicates that M. leprae is a very unique organism, and this future is important to understand the biological nature and/or pathogenicity of M. leprae, which remain unclear. We attempted to find the biological nature of M. leprae by detecting the gene and pseudogene regions transcribed at high level. We detected the genomic regions including pseudogenes and demonstrated that six out of twelve high expression regions were pseudogenes. In addition, its transcription level was changed when M. leprae infects macrophage. RNA was detected from genes, pseudogenes and non-coding regions. The expression levels of these regions were different among patients and a part of them is disappeared just after treatment. These results suggested that RNA derived from pseudogene and non-coding region have some function concerning the infection and/or intracellular parasitism and that the analysis of pseudogene and non-coding region expression pattern of M. leprae is available as a criterion for therapeutic effect and disease type of leprosy, and a prognostic marker.