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A growing number of functions are emerging for RNA interference (RNAi) in the nucleus, in addition to well-characterized roles in post-transcriptional gene silencing in the cytoplasm. Epigenetic modifications directed by small RNAs have been shown to cause transcriptional repression in plants, fungi and animals. Additionally, increasing evidence indicates that RNAi regulates transcription through interaction with transcriptional machinery. Nuclear small RNAs include small interfering RNAs (siRNAs) and PIWI-interacting RNAs (piRNAs) and are implicated in nuclear processes such as transposon regulation, heterochromatin formation, developmental gene regulation and genome stability. [ABSTRACT FROM AUTHOR]

The article focuses on a research related to the impact of epigenetic silencing. It discusses that MicroRNAs regulate gene expression by gene coding leading to their fission in plants and animals. It suggest that miRNAs might epigenetically regulate stress-responsive genes.The physiological regulation of this epigenetic miRNA-induced silencing pathway.

Discusses research being done on epigenetics. Reference to a study by J. Mager et al, published in a 2003 issue of 'Nature Genetics'; Information on X chromosome inactivation.

The article discusses inbreeding effects in epigenesis. It mentions about the omic technology which enhances the knowledge of inbreeding effects. It discovers epigenetics to the differential regulation of gene expression, imprinting and gene silencing. Epigenetic differences among natural population is being linked with the variations of DNA methylation.

The article offers information on the two antisense RNA transcripts, AIR and KCNQ1OT1. It mentions that the two antisense transcripts are normally expressed from paternally inherited chromosomes and are involved in silencing cis clusters of genes. It references two studies that show the effect of the antisense transcripts in gene-silencing and its direct, functional involvement in lineage-specific transcriptional repression, mediated via epigenetic modifications.

The article evaluates a research paper entitled "Role of nucleosomal occupancy in the epigenetic silencing of the MLH1 CpG island," by J. Lin and colleagues. The study demonstrates that for one promoter region cytosine methylation is accompanied by the presence of nucleosomes that are largely absent in this region in normal cells.