Small RNAs are found in eukaryotes and are responsible for regulation of chromatin structure, RNA processing and stability, translation and transcription. 24-nt small interfering RNA (siRNA) are known to mediate gene ...Small RNAs are found in eukaryotes and are responsible for regulation of chromatin structure, RNA processing and stability, translation and transcription. 24-nt small interfering RNA (siRNA) are known to mediate gene inactivation via the RNA-directed DNA methylation pathway (RdDM) and are important for natural heritable changes in plant species. DNA cytosine methylation can be maintained between generations and this may be important for accelerated adaption to stress conditions. Research is currently focused toward the epigenetic response to disease, the stability of DNA methylation over generations, the elucidation of newly discovered pathways for de novo DNA methylation, and the application of epigenetic variation to breeding programs. This review aims to give a brief but comprehensive examination on small RNAs and transgenerational epigenetic variation.展开更多
RNA silencing is an evolutionarily conserved mechanism in eukaryotic organisms induced by double-stranded RNA(dsRNA)and plays an essential role in regulating gene expression and maintaining genome stability.RNA silenc...RNA silencing is an evolutionarily conserved mechanism in eukaryotic organisms induced by double-stranded RNA(dsRNA)and plays an essential role in regulating gene expression and maintaining genome stability.RNA silencing occurs at both posttranscriptional levels through sequence-specific RNA degradation or translational repression and at transcriptional levels through RNA-directed DNA methylation and/or hetero-chromatin formation.RNA silencing pathways have been relatively well characterized in plants and animals,and are now also being widely investigated in diverse fungi,some of which are important plant pathogens.This review focuses primarily on the current understanding of the dsRNA-mediated posttranscriptional gene silencing pro-cesses in fungi,but also discusses briefly the known gene silencing pathways that appear to be independent of the RNA silencing machineries.We review RNA silencing studies for a variety of fungi and highlight some of the mechanistic differences observed in different fungal organisms.As RNA silencing is being exploited as a technology in gene function studies in fungi as well as in engineering anti-fungal resistance in plants and animals,we also discuss the recent progress towards understanding dsRNA uptake in fungi.展开更多
文摘Small RNAs are found in eukaryotes and are responsible for regulation of chromatin structure, RNA processing and stability, translation and transcription. 24-nt small interfering RNA (siRNA) are known to mediate gene inactivation via the RNA-directed DNA methylation pathway (RdDM) and are important for natural heritable changes in plant species. DNA cytosine methylation can be maintained between generations and this may be important for accelerated adaption to stress conditions. Research is currently focused toward the epigenetic response to disease, the stability of DNA methylation over generations, the elucidation of newly discovered pathways for de novo DNA methylation, and the application of epigenetic variation to breeding programs. This review aims to give a brief but comprehensive examination on small RNAs and transgenerational epigenetic variation.
文摘RNA silencing is an evolutionarily conserved mechanism in eukaryotic organisms induced by double-stranded RNA(dsRNA)and plays an essential role in regulating gene expression and maintaining genome stability.RNA silencing occurs at both posttranscriptional levels through sequence-specific RNA degradation or translational repression and at transcriptional levels through RNA-directed DNA methylation and/or hetero-chromatin formation.RNA silencing pathways have been relatively well characterized in plants and animals,and are now also being widely investigated in diverse fungi,some of which are important plant pathogens.This review focuses primarily on the current understanding of the dsRNA-mediated posttranscriptional gene silencing pro-cesses in fungi,but also discusses briefly the known gene silencing pathways that appear to be independent of the RNA silencing machineries.We review RNA silencing studies for a variety of fungi and highlight some of the mechanistic differences observed in different fungal organisms.As RNA silencing is being exploited as a technology in gene function studies in fungi as well as in engineering anti-fungal resistance in plants and animals,we also discuss the recent progress towards understanding dsRNA uptake in fungi.
