How does RNA polymerase move along the DNA helix?
As RNA polymerase moves along the DNA helix it follows a single strand. The two DNA strands are unwound locally by a helicase enzyme. However, after some distance, I imagine that either the polymerase must move around the axis of the DNA OR the DNA must somehow be rotated along it's length to relieve the twisting by the polymerase.
Do ribosomes move along the mRNA strand?
Of course, the length (and thus the mass) of an mRNA varies quite a lot, so it would seem likely that sometimes it's the ribosome that moves mostly, sometimes it's the mRNA, and sometimes it's both. Also, as shigeta and others have pointed out, there can be more than one ribosome attached to the same mRNA strand.
Is the mRNA moving during translation?
Movement is relative. The real events happening in translation are the conformational changes of ribosome makes itself continuous reading the base sequentially. Please refer the biochemistry textbook or cell biology textbook. Indeed, if the ribosome is anchored, you may say the mRNA is moving.
Are there any genes for RNAs other than mRNA?
B. There are also genes for RNAs other than mRNA. C. Each gene codes for one protein. D. The species is highly evolved. E. There are 20,000 genes. Which of the following types of mutation, resulting in an error in the mRNA just after the AUG start of translation, is likely to have the most serious effect on the polypeptide product?
Which way does RNA go?
RNA polymerase synthesizes an RNA transcript complementary to the DNA template strand in the 5' to 3' direction. It moves forward along the template strand in the 3' to 5' direction, opening the DNA double helix as it goes.
Is RNA transcribed in the 5 to 3 direction?
RNA polymerase synthesizes an RNA strand complementary to a template DNA strand. It synthesizes the RNA strand in the 5' to 3' direction, while reading the template DNA strand in the 3' to 5' direction.
Does RNA have direction?
By convention, single strands of DNA and RNA sequences are written in a 5′-to-3′ direction except as needed to illustrate the pattern of base pairing.
How does RNA move in a cell?
Recent studies suggest that RNA can move from donor cells and regulate genes in recipient cells through sequence-specific interactions with other RNA.
What does 5 prime and 3 prime mean?
2:004:185' and 3' ends of DNA.mov - YouTubeYouTubeStart of suggested clipEnd of suggested clipNumber five now you'll notice that the phosphate is attached to carbon number five and that gives usMoreNumber five now you'll notice that the phosphate is attached to carbon number five and that gives us our five prime end of this nucleotide. The three prime end is where this this hydroxyl.
Which end of DNA is 5 and 3?
0:432:245' 3' ends of DNA and RNA - YouTubeYouTubeStart of suggested clipEnd of suggested clipThe 5 prime end of DNA refers to the fifth carbon of a sugar that connects to the phosphate.MoreThe 5 prime end of DNA refers to the fifth carbon of a sugar that connects to the phosphate.
In what direction is DNA read?
5′-3′ directionWhich way's which? When we look at a sequence of DNA, we read it in the 5′-3′ direction. The relative positions of genes or other sites along a DNA strand can be described as upstream (towards the 5′ end) or downstream (towards the 3′ end).
What is the 5 to 3 direction?
DNA is always synthesized in the 5'-to-3' direction, meaning that nucleotides are added only to the 3' end of the growing strand. As shown in Figure 2, the 5'-phosphate group of the new nucleotide binds to the 3'-OH group of the last nucleotide of the growing strand.
What direction does RNA polymerase move along the DNA?
3' to 5' directionAt this point, RNA polymerase begins moving down the DNA template strand in the 3' to 5' direction, and as it does so, it strings together complementary nucleotides. By virtue of complementary base- pairing, this action creates a new strand of mRNA that is organized in the 5' to 3' direction.
How does RNA move from nucleus to cytoplasm?
During eukaryotic gene expression, different classes of RNA molecules are synthesized in the nucleus and are exported to the cytoplasm by mobile export receptors. Export of tRNA requires a specific export receptor called exportin-t, a member of the RanGTP-dependent karyopherin superfamily.
How does RNA move from inside of the nucleus to the cytoplasm?
In the nucleolus, new ribosomal RNA combines with proteins to form the subunits of the ribosome. The newly made subunits are transported out through the nuclear pores to the cytoplasm, where they can do their job.
How does mRNA move out of the nucleus?
Messenger RNA, or mRNA, leaves the nucleus through pores in the nuclear membrane. These pores control the passage of molecules between the nucleus and the cytoplasm. Before the mRNA arrives in the cytoplasm, however, it must be processed.
What enzyme assembles the RNA in a 5 3 direction?
RNA polymeraseAt this point, RNA polymerase begins moving down the DNA template strand in the 3' to 5' direction, and as it does so, it strings together complementary nucleotides. By virtue of complementary base- pairing, this action creates a new strand of mRNA that is organized in the 5' to 3' direction.
Do you read DNA from 5 to 3?
Any single strand of DNA/RNA will always have an unbound 5' phosphate at one end and an unbound 3' hydroxyl group at the opposite end. DNA is always read in the 5' to 3' direction, and hence you would start reading from the free phosphate and finish at the free hydroxyl group.
Why does DNA and RNA only grow in the 3 direction?
Because the original strands of DNA are antiparallel, and only one continuous new strand can be synthesised at the 3' end of the leading strand due to the intrinsic 5'-3' polarity of DNA polymerases, the other strand must grow discontinuously in the opposite direction.
Which of the following processes does not take place in the 5 → 3 direction?
So, the correct option is 'Production of mRNA'.
What is the reference point for DNA and RNA polymerase?
While the new mRNA is big, it would never be as big as the whole genome, so the reference point is the DNA molecule. Plus, the functioning of the movement of this enzymes is quite similar to other proteins that move "climbing" long polymers, such as actin polymers or microtubules.
How does ATP affect polymerases?
The polymerases consume ATP, which enable them to suffer cyclic conformational changes (one change per ATP consumed), which allows the complex to attach to the molecule and detach. Once the complex has detached, by simple diffusion it moves in a random direction. Then, it attaches again. If the movement has occurred in the right sense, it will stay where it ended, while if it has gone in the wrong sense it will return to its previous position. As only a few movements are allowed, the complex will only move in that sense, even if the motor force is random.
Can RNA polymerases transcribe genes?
I would have to agree that the "transcription factories" (several RNA Polymerases and some other proteins combined) attract DNA and transcription factors, and then start transcription while they remain static. One such factory can actually transcribe many genes at once. Most books and online sources still describe the Polymerase as moving along the DNA and carrying out transcription, but this has been proven wrong. source: http://www.ncbi.nlm.nih.gov/pubmed/8799830
Do polymerases move DNA?
There is an alternative view that polymerases are sort of DNA motors that move DNA while they themselves remain static. I cannot find that reference now but I read this ~5 years back in a Nature Reviews article. The notion of transcription and replication factories also fits this model.
Which theoretical model describes the movement of this kind of proteins?
One of the theoretical models that describes the movement of this kind of proteins is the model of rectified thermal diffusion, based on Richard Feynman's idea of the Brownian ratchet. A Brownian ratchet is a device that allows the conversion of Brownian random movements into a directional force.
Does RNA polymerase move around the DNA helix?
The two DNA strands are unwound locally by a helicase enzyme. However, after some distance, I imagine that either the polymerase must move around the axis of the DNA OR the DNA must somehow be rotated along it's length to relieve the twisting by the polymerase .
How does RNA polymerase transcribe?
C. RNA polymerase transcribes through a stop codon, causing the polymerase to stop advancing through the gene and release the mRNA. D. Once transcription has initiated, RNA polymerase transcribes until it reaches the end of the chromosome.
What tRNA binds to the growing polypeptide?
A. Use the following information to answer the question. A transfer RNA (#1) attached to the amino acid lysine enters the ribosome. The lysine binds to the growing polypeptide on the other tRNA (#2) in the ribosome already.
Which enzyme randomly assembles nucleotides into a polynucleotide polymer?
Use the following information to answer the question.The enzyme polynucleotide phosphorylase randomly assembles nucleotides into a polynucleotide polymer.
What is each amino acid in a protein encoded by?
Each amino acid in a protein is encoded by a triplet of nucleotides. B. Many genes are subject to alternative RNA splicing. C. Most eukaryotic genes and their RNA transcripts have long noncoding stretches of nucleotides that are not translated. C.
How many nucleotides are in a transcription unit?
E. none of the proteins in the cell will contain phenylalanine. C. The average length of a transcription unit along a eukaryotic DNA molecule is about 27,000 nucleotide pairs, whereas an averaged-sized protein is about 400 amino acids long.
Where is the molecule digested?
A. The molecule is digested by restriction enzymes in the nucleus.
Can ribosomal subunits assemble faster?
A. It could allow ribosomal subunits to assemble at faster rates.
