Noncoding RNAs and chromatin structure.
A number of examples of noncoding RNA-connected chromatin modifications in eukaryotes has been recently revealed. Four cases are under detailed consideration in the present review, namely Xist RNA-dependent X-chromosome inactivation in mammals, roX RNA-dependent hyperactivation of X-chromosome in the fruit fly (in both cases the goal is dosage compensation, equalization of transcription level from two X chromosomes in females and one in males), and two examples of RNAi-connected down-regulation of transcription--siRNA-dependent heterochromatin formation in fission yeast and RdDM (RNA-dependent DNA methylation) in plants (FWA gene regulation in Arabidopsis). Although overall quite different, each phenomenon demonstrates some common features of RNA-driven chromatin modification process, including the role of RNA in aiming of chromatin-modifying protein complexes to their targets and subsequent formation of self-maintaining specific chromatin conformation (DNA methylation, changes in histone code, and binding of self-assembling protein complexes).
Lavrov
S A
SA
Institute of Molecular Genetics, Russian Academy of Sciences, pl. Kurchatova 2, 123182 Moscow, Russia. slavrov@img.ras.ru
Kibanov
M V
MV
D000818:Animals; D002843:Chromatin / Q000737:chemistry*; D019175:DNA Methylation; D004303:Dosage Compensation, Genetic; D004331:Drosophila melanogaster; D005786:Gene Expression Regulation; D006801:Humans; D008958:Models, Molecular; D008968:Molecular Conformation; D009707:Nucleosomes / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D034622:RNA Interference; D022661:RNA, Untranslated; D014158:Transcription, Genetic; D014960:X Chromosome
D002843:Chromatin; D009707:Nucleosomes; D022661:RNA, Untranslated