What would be the most likely effect of a mutation in a snoRNA that changed the antisense sequence?
The snoRNP would be assembled, but rRNA molecules would not be modified
.
What might be the effect of a mutation in the promoter?
Mutations in the promoter region resulted in
a change in DNA binding pattern of the AP-2 transcription factor
. Modulation of transcription factors binding pattern might lead to a change of sequence-specific interaction between DNA-protein or protein-protein in the transcription initiation complex.
What is the function of the poly A tail?
The poly-A tail makes
the RNA molecule more stable and prevents its degradation
. Additionally, the poly-A tail allows the mature messenger RNA molecule to be exported from the nucleus and translated into a protein by ribosomes in the cytoplasm.
What is the first step in the production of a miRNA group of answer choices?
Production of miRNA precursors in animal cells. The first step is
the generation in the nucleus of an approximately 60 nt long hairpin RNA
, called the precursor miRNA, or pre-miRNA (Figure 2a), the prototype being lin-4L observed by Lee et al. (1993).
What is the basis for detecting MEX 3 RNA by in situ hybridization?
The worms ate the plasmids and synthesized the RNA in their own cells. What is the basis for detecting mex-3 RNA by in situ hybridization?
A labeled RNA probe is complementary to mex-3 mRNA
. Fire and Mello studied the effect of RNAs made from plasmids on gene expression in the nematode C.
What occurs in a deletion mutation?
A deletion mutation occurs when
a wrinkle forms on the DNA template strand and subsequently causes a nucleotide to be omitted from the replicated strand
(Figure 3). Figure 3: In a deletion mutation, a wrinkle forms on the DNA template strand, which causes a nucleotide to be omitted from the replicated strand.
What happens if there is a deletion in the promoter?
The contribution of a region of the promoter can be observed by the level of transcription. If a mutation or deletion changes the level of transcription, then it is known that that
region of the promoter may be a binding site or other regulatory element
.
Does bacterial RNA have a poly A tail?
Investigations of specific transcripts confirmed that
only a small fraction of bacterial RNAs harbors poly(A) tails
which are mostly less than 20 As in length whereas the majority of molecules are not adenylated.
What are 3 important functions of these modifications to the 5 and 3 ends?
- They facilitate the export of the mature mRNA from the nucleus.
- They help protect the mRNA from degradation.
- They help ribosomes attach to the 5′ end of the mRNA once it reaches the cytoplasm.
Does all RNA have poly A tail?
Many eukaryotic non-coding RNAs are always polyadenylated at the end of transcription. There are small RNAs where the
poly(A) tail is seen only in intermediary forms
and not in the mature RNA as the ends are removed during processing, the notable ones being microRNAs.
How does siRNA affect gene expression?
The siRNA-induced post transcriptional gene silencing starts with the assembly of the RNA-induced silencing complex (RISC). The complex
silences certain gene expression by cleaving the mRNA molecules coding the target genes
. … This cleavage results in mRNA fragments that are further degraded by cellular exonucleases.
How do siRNA and miRNA affect gene expression?
Here, we demonstrate that an
endogenously encoded human miRNA is able to cleave an mRNA bearing fully complementary target sites
, whereas an exogenously supplied siRNA can inhibit the expression of an mRNA bearing partially complementary sequences without inducing detectable RNA cleavage.
How does miRNA affect gene expression?
microRNA controls gene expression mainly by
binding with messenger RNA (mRNA) in the cell cytoplasm
. Instead of being translated quickly into a protein, the marked mRNA will be either destroyed and its components recycled, or it will be preserved and translated later.
What process do antisense RNAs prevent?
Antisense RNAs play the crucial role in
regulating gene expression
at multiple levels, such as at replication, transcription, and translation. In addition, artificial antisense RNAs can effectively regulate the expression of related genes in host cells.
Why is a genome needed for RNA Seq analysis?
Summary of RNA-Seq. Within the organism,
genes are transcribed and (in an eukaryotic organism) spliced to produce mature mRNA transcripts (red)
. … These sequences can then be aligned to a reference genome sequence to reconstruct which genome regions were being transcribed.
Is Southern blotting the same as gel electrophoresis?
A Southern blot is a
laboratory method used
to detect specific DNA molecules from among a many other DNA molecules. The technique was named after its inventor, Edward Southern. … The mixture of DNA fragments is then separated according to size by way of a technique called gel electrophoresis.
