The concept of gene regulation by RNAs wasn’t always as well accepted as it is today, and even now some view the idea as controversial. The text RNA and the Regulation of Gene Expression, edited by Kevin Morris, explores the evidence that has convinced many top researchers of the important roles that RNAs have in controlling gene function.
Although it’s been a few years since it was first published, and there’ve been numerous advancements in the RNA field, this book still holds up as a great reference for students and researchers. The variety of topics and quality of chapters creates a solid base of knowledge to launch further RNA explorations. RNA and the Regulation of Gene Expression is packed with 14 chapters, but here’s a taste of a few of our favorites:
MicroRNA-Mediated Regulation of Gene Expression
Lena Chin and Frank Slack
Since their discovery in C. elegans, hundreds of plant and animal microRNAs have been identified. If current prediction models are correct, roughly 1-3% of genomic DNA encodes for these small, regulatory RNAs. miRNAs can block protein production by binding to their target mRNAs and post-transcriptionally regulating gene expression. The exact gene expression down-regulation isn’t clear, but several main theories have emerged including target degradation, localization to P-bodies, inhibition of translation initiation or elongation, mRNA deadenylation, and mRNA destabilization.
The Role of Non-Coding RNAs in Controlling Mammalian RNA Polymerase II Transcription
Stacey Wagner, Jennifer Kugel and James Goodrich
Recent research has led to the understanding that RNAs actually play a very large part in regulating mammalian transcription, aided by discoveries of a number of RNA transcriptional regulators, some of which can control entire transcriptional programs.
Other studies have shown that a much more of the genome is transcribed than previously thought, and a lot of it doesn’t encode proteins; which is why those transcripts are called non-coding RNAs (ncRNA). With this knowledge, researchers started searching for ncRNA transcriptional regulators, and most stages of transcription are now shown to be targeted by a ncRNA.
This chapter reviews ncRNAs that control mammalian mRNA transcription, groups them by the transcription stage that they target, and explores the next steps to further our understanding of ncRNAs.
RNA Mediated Transcriptional Gene Silencing: Mechanism and Implications in Writing the Histone Code
Three distinct mechanisms appear to be involved in creating or maintaining epigenetic modifications; DNA methylation, RNA-associated silencing, and histone modifications. Research has shown that RNA can specifically direct epigenetic modifications to targeted loci within promoter regions, causing silencing. This regulatory effect can be transcriptional, and works through an RNA interference based mechanism (RNAi) using the antisense strand of small-interfering RNAs (siRNAs).
RNA mediated transcriptional gene silencing (TGS), altered DNA methylation as well creating a hidden layer of complexity in gene regulation where RNA basically regulates DNA epigenetically.
The EpiGenie Verdict
If you want to find in-depth background info on RNAs and the various ways they alter gene regulation, this textbook is a really good place to start.
Pick up a copy of RNA and the Regulation of Gene Expression at the Horizon Press Website.