What is the backbone of RNA called?
A sugar-phosphate backbone (alternating grey-dark grey) joins together nucleotides in a DNA sequence. The sugar-phosphate backbone forms the structural framework of nucleic acids, including DNA and RNA.
Would you expect mRNA or rRNA to be degraded more quickly in the cell?
Turnover of mRNA should be rapid to ensure that the cell can respond quickly when specific proteins are needed. Ribosomal subunits, including their rRNA component, can be recycled for many rounds of protein synthesis. As a result, mRNA is degraded more rapidly than rRNA.
What is the sugar backbone of RNA?
In DNA, the sugar involved is deoxyribose. On on the other hand, the sugar in the backbone of RNA is called ribose.
Why is mRNA degradation important?
In eukaryotic cells, the degradation of mRNA is an essential determinant in the regulation of gene expression, and it can be modulated in response to developmental, environmental, and metabolic signals.
How is mRNA broken down?
Histone mRNA degradation begins when a string of uridine molecules are added to the tail end of the molecule — a process known as oligouridylation. This signals a complex of proteins known as the exosome to begin degrading the mRNA.
What forms the backbone strands of the DNA double helix What connects these strands in the middle?
The sugar and phosphate molecules form the outside strands of the helix, and the bases pair together in the middle, forming hydrogen bonds that hold the two sides of the helix together.
What parts of the nucleotide make up the backbone?
The sugar and phosphate group make up the backbone of the DNA double helix, while the bases are located in the middle. A chemical bond between the phosphate group of one nucleotide and the sugar of a neighboring nucleotide holds the backbone together.
What protects mRNA degradation?
After export to the cytoplasm, mRNA is protected from degradation by a 5′ cap structure and a 3′ poly adenine tail. In the deadenylation dependent mRNA decay pathway, the polyA tail is gradually shortened by exonucleases.
How does mRNA degradation occur?
Most mRNAs are degraded by a deadenylation-dependent pathway in which the poly(A) tail is degraded by the CCR4-NOT or PARN. Subsequently, the 5′ cap of the mRNA is removed by the DCP1-DCP2 decapping complex. Following cap removal, the mRNA is degraded by the XRN1 exoribonuclease in a 5′ to 3′ direction.
What is the structure of mRNA?
An mRNA molecule is a short, single-stranded molecule containing adenine, cytosine, guanine and uracil, exons, 5′-cap and 3′-poly-tail. Introns have been spliced out automatically by the mRNA itself or by the spliceosome. 2. Name the location and cellular machinery involved in mRNA transcription and translation.