Question

RNA's ability to fold in on itself has been well-characterized over the last couple of decades. In addition to conferring enzymatic properties, what other functions does this folding perform? Please frame your answers with respect to gene regulation (by RNA) and include information about siRNA's, snoRNA's, micro RNA's or similar (discuss at least one).

No handwritten responses or pictures. PLease type text out. Please number answers

Answer 1

In addition to conferring enzymatic properties the other functions performed by the folding of RNA is to storing the noncoding regions of RNA into a 3D structure.

These noncoding RNAs assit in many essential functions which are still being enumerated and defined.

As a group these RNAs are frequently referred to as small regulatory RNAs.In eukaryotes they have been further classified into a number of subcategories.

These regulatory RNAs exert their effects through a combination of complementary base pairing, complexing with protiens and their own enzymatic activities.

1.Small Nuclear RNAs(snRNAs): These play an important role in gene regulation by the function of splicing.snRNAs are found in nucleus and are tightly bound to protiens in complexs called small nuclear ribonucleoprotiens (snurps).The most abundant of these are U1,U2,U4/U6,U5.All these are involved in splicing pre-mRNA to give rise to mature mRNA.

2.Small interfering RNAs(siRNA): These molecules are only 21 to 25 base pairs in length.These work to inhibit gene expression.One strand of double stranded siRNA can be incorporated into a complez called RISC.This RNA containing complex can then inhibit transcription of mRNA molecule that has a sequence complementary to its RNA component.

3.Small Nuclear RNAs (snRNAs):Molecules called small nuclear RNAs were isolated from nucleolar extraxts because of their abundance in this structure.These molecules function to process RNA molecules often resulting in the methylation and psuedouridylation of specific nucleosides.

The ongoing discovery of new small regulatory RNA molecules suggests that additional functions may be yet to be uncovered.