RNAi and Functional Genomics

These flashcards cover key concepts from the lecture notes on RNA interference and functional genomics.

What is Functional Genomics?

It is the genome scale determination of gene function including biochemical, physiological, cell biology, and developmental aspects.

What did the Nobel Prize in Physiology or Medicine 2006 recognize Andrew Z. Fire and Craig C. Mello for?

They were awarded for their discovery of RNA interference - gene silencing by double-stranded RNA.

What is RNA interference (RNAi)?

RNAi is a post-transcriptional gene silencing mechanism that involves the use of double-stranded RNA.

What does 'RISC' stand for in the context of RNAi?

RISC stands for RNA-induced Silencing Complex, which unwinds dsRNA and associates with target mRNA.

What are the main methods of introducing dsRNA into cells for RNAi?

dsRNA can be delivered by bacterial feeding, soaking, injection, or transgenesis.

What does the rrf-3 mutant strain indicate in the context of RNAi?

The rrf-3 mutant enhances sensitivity to dsRNA, particularly affecting the nervous system and increases the detection of phenotypes.

What are the common applications of RNAi in functional genomics?

RNAi is used for genome-wide screens to identify gene functions, associated phenotypes, and potential drug targets.

How many genes did the RNAi feeding library in C. elegans silence?

The library silenced approximately 86% of the genome or around 16,000 genes.

What are potential drawbacks of using siRNAs in gene silencing?

Drawbacks include transient response, transduction problems, non-renewable nature, and off-target gene silencing.

Why is Caenorhabditis elegans a model organism for studying obesity?

C. elegans shares conserved energy homeostatic mechanisms with mammals, making it useful to identify fat-regulating genes.

What is the significance of the Dicer enzyme in RNA interference?

Dicer processes double-stranded RNA into smaller fragments that are then used to silence target mRNA.

What are the two types of genetic screens mentioned in the notes?

Forward genetic screens and reverse genetic screens.

What were the results of RNAi on fat storage genes in C. elegans?

305 gene inactivations were identified that reduced body fat, while 112 increased fat storage.

What does RNAi stand for?

RNA interference.

What is the role of double-stranded RNA (dsRNA) in RNAi?

dsRNA is the molecule that triggers the RNA interference mechanism to silence gene expression.