FAN Flashcards
The introduction of double stranded RNA (dsRNA) into a cell causes degradation of the ___________ mRNA.
complementary
RNA interference (RNAi) is a phenomenon in which the introduction of ________ into a diverse range of organisms and cell types causes degradation of the complementary mRNA, thereby specifically knocking down the expression of genes.
double-stranded RNA (dsRNA)
siRNA stands for _______.
small interfering RNA
Long dsRNAs are cleaved into short 21-25 nucleotide siRNAs by a ribonuclease known as _________.
Dicer-2
The siRNAs made by Dicer-2 assemble with protein components into a/an __________.
RNA-induced Silencing Complex (RISC)
Activated RISC then binds to the complementary transcript by _______ interactions between the siRNA strand and the mRNA.
base pairing
Sequence-specific degradation of mRNA results in ________.
gene silencing
Cell response to dsRNA is more complicated; it triggers a cellular immune response involving the release of ________ that ultimately kills the cell. This is an issue!
interferon
In 2001, it was discovered that if ________ are introduced into mammalian cells, they avoid the activation of cellar inflammation and death signaling; a gene-specific silencing process can be started.
small interfering RNAs (siRNAs) (<50 nt at the time; now usually 19-21nt)
The process for determining an effective siRNA has ____ rules.
5
The 5’ end of the antisense strand of a functional siRNA should have a/an _____ or _____.
A or U
The 5’ end of the sense strand of a functional siRNA should have a/an _____ or ______.
G or C
A functional siRNA should have greater than ______ A or U nucleotides in the seed sequence (second - ninth nt of antisense strand from the 5’ end).
4
The cleavage site (9-10 nt) of a functional siRNA should be an ____ and _____.
A/U
A functional siRNA should have ________ 2-nt 3’-overhangs.
unilateral
shRNA stands for ________.
short hairpin RNA
shRNA is used for _______ expressing double-stranded siRNA.
long-term
The spacer in shRNA is _________.
TCAAGAG
siRNA delivery is used in _____ and _______ research.
basic, clinical
Some applications of ______ include cancer, hypercholesterolemia, infections, developmental defects, and neurodegenerative diseases.
siRNA
In principle any gene can be silenced by ______.
small interfering RNAs (siRNAs)
RNAi provides a rapid approach for assessing the ________ and developing siRNA drug to treat human disease.
loss-of-gene function
Long dsRNA, synthetic dsRNA, and shRNA can be processed to siRNA via ________, then induce the sequence-specific degradation of complementary mRNA.
dicer
The phenomenon of RNA-mediated gene silencing is called ___________.
RNA interference (RNAi)