Term
|
Definition
|
|
Term
| What is the difference between RNA and DNA. |
|
Definition
| RNA is missing a 2' -OH whereas DNA has the 2' -OH |
|
|
Term
| Why is it important that the DNA backbone is negatively charged? |
|
Definition
| The negative charge repels nucleophiles in solution. |
|
|
Term
| Why is it important that DNA is missing its 2' Hydroxyl? |
|
Definition
| This makes it more stable than RNA because the hydroxyl cannot then undergo nucleophilic attack of the phosphate. If it did, it would cleave the molecule. |
|
|
Term
|
Definition
|
|
Term
| How are bases and sugars bound? |
|
Definition
| Beta- glycosidic linkages |
|
|
Term
| How do you name a nucleoside? |
|
Definition
| use the prefix from the sugar and then add -sine to the end. ex: adenine+deoxyribose=adenosine |
|
|
Term
| What position is the phospate at? |
|
Definition
|
|
Term
| Primes designate position on what? |
|
Definition
| Primes designate the position on ribose whereas no prime shows position on the base. |
|
|
Term
| When writing DNA sequence, which direction do you write it? |
|
Definition
|
|
Term
| What is on the 5' end of DNA? The 3' end? |
|
Definition
| Phosphate is on 5', -OH is on 3' end. |
|
|
Term
| What is the significance of the 3.4 angstrom spacing in a x-ray crystallography of DNA? |
|
Definition
| The bases are located 3.4 angstrom above/below each other along the axis of the DNA molecule. |
|
|
Term
| How long does a DNA helix turn take? |
|
Definition
| 34 angstrom which is about 10 bases |
|
|
Term
| Which base pairs result in 2 hydrogen bonds? 3 hydrogen bonds? |
|
Definition
| A-T is 2 hydrogen bonds, C-G is 3 hydrogen bonds. |
|
|
Term
| Why are the hydrogen bonding capabilities of the bases important in DNA structure? |
|
Definition
| Hydrogen bonding creates the need for specificity for duplex formation. |
|
|
Term
| Why is hydrogen bonding of DNA entropically favored? |
|
Definition
| Hydrogen bonding gives the release of 2 water molecules that were originally tied up in hydrogen bonding favoring entropy. |
|
|
Term
| A/T ratios never fluctuate, but A/G ratios do. Why? |
|
Definition
| Specificity of base paring causes a 1:1 ratio of A/T and C/G base pairs. A/G ratios are usually stable along an organism's genome unless some is introduced from somewhere else (phage, etc)... |
|
|
Term
| What forces add to the stability of the DNA double helix? |
|
Definition
| Hydrogen bonding of base pairs, negatively charged backbone, base stacking |
|
|
Term
|
Definition
| The hydrophobic affects between stacked bases that have beneficial van Der Waals interactions to add to DNA stability. |
|
|
Term
| Does DNA absorb light better as a double helix or a single strand? |
|
Definition
| A single strand so that the bases aren't blocked by the DNA backbone. DNA absorbs at approximately 260 nm. |
|
|
Term
| Increasing the temperature of DNA causes it to what? |
|
Definition
|
|
Term
| Why are counterions important in solution with DNA? |
|
Definition
| The counterions help shield the repulsive effects of the negatively charged phosphates on other adjacent backbone phosphates. |
|
|
Term
| DNA melting temperature depends on what factors? |
|
Definition
| Counterion concentrations, strand length, number of A/T's in a row (cooperativity and base stacking) and number of C/G (higher temp) vs A/T (lower temp) residues. |
|
|
Term
| When DNA is less hydrated, what form does it generally take? What form is most common in humans? |
|
Definition
| Less hydrated formes A type DNA where B type is most common in life. |
|
|
Term
| When is a propeller twist most common? |
|
Definition
|
|
Term
| What is the significance of the major groove and minor grooves on DNA? |
|
Definition
| The major groove allows proteins to read interesting signals on the inside of the major groove through interactions with the bases. |
|
|
Term
|
Definition
| Alternating purines and pyrimidines can form left handed helices in high salt concentrations. |
|
|
Term
| What is a direct repeat and an Inverted repeat? |
|
Definition
| A direct repeat is a repeat of a sequence on the same strand of DNA that reads the same both times. An inverted repeat is one where the repeat reads in the reverse order of the repeated segment and often can create structures called hairpins where the inverted repeat hydrogen bonds with the same strand of DNA. |
|
|
Term
| What is a cruciform and why is it important? |
|
Definition
| A cruciform is part of a DNA helix where each strand forms a hairpin at the same location on the helix. This is important for regulation. |
|
|
Term
| How can RNA hydrogen bonding be different than DNA bonding? |
|
Definition
| RNA hydrogen bonding can bond with 3 bases at a time if needed to confer unique geometries. |
|
|
Term
| What is linking number? Twist? Writhe? |
|
Definition
| Lk= (Tw+Wr) or the number of times the DNA strand winds in a right handed direction around the helical axis. Tw= "apparent linking number". Wr= Number of supercoils |
|
|
Term
| How does a type 1 topoisomerase work? |
|
Definition
| Its tyrosine residue nucleophilic attacks one strand of DNA, it cuts that strand, lets it untwist (with it's own built up torque) then re-attaches the strand. This is all without ATP. |
|
|
Term
| How does a type 2 topoisomerase work? |
|
Definition
| 1. The enzyme binds to the helix, 2. ATP binds to the enzyme and causes a conformational change. 3. The double helix is cut and part of the helix downstream is allowed to pass through. 4. The strand is reconnected, 5. ATP is hydrolized and the enzyme releases itself. |
|
|
Term
| In the Meselson and Stahl experiment, what was proven? |
|
Definition
| Semi-conservative replication was demonstrated. The parent population had all labeled DNA, the 1st offspring had 50%, then 25%... etc. |
|
|
Term
| What is required for DNA replication? |
|
Definition
| deoxynucleoside 5'-triphosphates (dATP, dGTP, dCTP,dTTP), Mg2+, DNA template, Primer, and DNA polymerase. |
|
|
Term
| Why is DNA synthesis thermodynamically favored? |
|
Definition
| The product includes the formation of pyrophosphate which is quickly degraded pushing the reaction to the right. |
|
|
Term
| How does DNA polymerase proofread? |
|
Definition
| The tight binding between the fingers and thumb can quickly identify a mismatched pair. |
|
|
Term
| Why is Mg2+ important in DNA polymerase? |
|
Definition
| The Mg2+ ions are coordinated in the palm region by Asp residues. The Mg2+ increases the partial positive charge on the alpha phosphors. It also stabilizes the pentacovalent transition state and finally it facilitates the displacement of pyrophosphate. |
|
|
Term
| What exactly are the two ways that DNA polymerase proofread? |
|
Definition
| 1. Minor groove interactions ensure proper hydrogen bonding. 2. The binding of the incoming nucleotide causes a conformational change where the finger region moves downward to make a tight pocket. If the incorrect base is present, this pocket will not yield a site that is capable of chemistry. |
|
|
Term
| How is DNA replication initiated in prokaryotes? |
|
Definition
| The enzyme primase comes in and lays down a strip of RNA primer. This allows DNA polymerase to synthesisze DNA off of the RNA primer. Once the DNA has been formed, the RNA primer gets hydrolyzed and is replaced by DNA. |
|
|
Term
| What direction does DNA replication move? |
|
Definition
|
|
Term
| What enzyme seals breaks in DNA? |
|
Definition
| DNA ligase. The reaction is favorable due to the release and subsequent breakdown of pyrophosphate. |
|
|
Term
|
Definition
| Helicase binds to a single strand of DNA. ATP binds and causes a conformational change. ATP is hydrolyzed causing the frontal subunit to rachet forward, undwinding more DNA. The helicase unwinds 3' to 5'. |
|
|
Term
| What does it mean to be processive? |
|
Definition
| It means that the enzyme can catalyze many consecutive reactions without releasing substrate. |
|
|
Term
| What is the purpose of the DNA clamp? |
|
Definition
| Keeps the DNA associated with DNA Polymerase 3 making the enzyme highly processive. |
|
|
Term
| What are the differences between DNA polymerase I, II and III? |
|
Definition
| I fills in gaps in the lagging strand and also in DNA repair. II: Exclusivey participates in DNA damage repair. III: Catalyzes replication on the leading strand. |
|
|
Term
|
Definition
| SSBs are single stranded binding proteins and they bind with single stranded DNA during replication in order to prevent against re-annealing of the helix. |
|
|
Term
| What is the purpose of the clamp loader? |
|
Definition
| The clamp loader: 1. Loads the polymerases, 2. Helps keep polymerases together so that the lagging strand does not get too far behind the leading strand. |
|
|
Term
| What is the significance of an A/T rich sequence? |
|
Definition
| The one less hydrogen bond makes it easier for that segment of DNA to be separated. |
|
|
Term
| What must occur for E. coli chromosomal replication to start? |
|
Definition
| 1. DnaA hexamer binds at several locations on the chromosome. 2. DnaA opens single-stranded site for primase to work. 3. DNA polymerase III holoenzyme assembles and DnaA oligomer disassembles. |
|
|
Term
| Name some of the differences between prokaryotes and eukaryotes for DNA replication: |
|
Definition
| 1. Eukaryotes have multiple origins of replication where prokaryotes only have one ori. 2. Eukaryotes have a polymerase that is used specifically to initiate replication and another polymerase that is more processive to finish the job. |
|
|
Term
| What are the consequences of telomeres? |
|
Definition
| Telomeres are structures at the ends of eukaryotic chromosomes in which some DNA is not replicated due to the RNA primer needed for initiation. Without the action of telomerase, the chromosome would get shorter upon each replication cycle. |
|
|
Term
| How does telomerase work? |
|
Definition
| Telomerase binds to the G-rich sequence at the end of chromosomes and elongates the chromosome by acting as a pseudo-template. Once a few bases have been added, the telomerase translocates by shifting down allowing more bases to be added. |
|
|
Term
| What is Huntington's disease? |
|
Definition
| Huntington's disease is a trinucleotide repeat that causes one strand of DNA to anneal to itself causing a structure similar to the onces found in RNA secondary structure. |
|
|
Term
|
Definition
| Hydroxyl radicals interact with guanine causing one of the nitrogens to be replaced by a carbonyl group. This can cause 8-Oxoguanine to form hydrogen bonds with Adenine rather than cytosine. |
|
|
Term
|
Definition
| Hypoxanthine is adenine with its nitro group replaced by a carbonyl. It can cause impropper base pairing with Cytosine. |
|
|
Term
|
Definition
| Adjacent thymine molecules cyclize in the presence of UV light. This cyclization is incompatible with the structure of the double helix. |
|
|
Term
| What is the importance of the epsilon subunit in DNA pol III? |
|
Definition
| It acts as a 3' to 5' exonuclease. Wrong base pairing causes a weak interaction with the polymerase. This causes the DNA strand to flop around freely until it gets into the exonuclease active site where it is cleaved. |
|
|
Term
| How does mismatch repair occur in E. coli? |
|
Definition
| Mut S binds to the mismatch on the parental DNA strand. Mut H then moves to the new (unmethylated) DNA strand more 3' of the mismatch and marks the spot. This spot exonuclease 1 recognizes and clears a strip of bases. DNA polymerase III is then free to come in and try again. |
|
|
Term
| How does Mut S know which strand of DNA is the new strand and which is the parental strand? |
|
Definition
| The methylation state determines this. When new DNA is made it is unmethylated until methylase has time to act upon it. The parental DNA is already methylated. |
|
|
Term
| How does Base-Excision repair work? |
|
Definition
| Enzyme AlkA detects 3-methyladenine, flips the base out of the helix and cleaves the glycosidic bond. 2. AP endonuclease recognizes this site and cleaves the backbone. 3. Deoxyribose phosphodiesterase removes deoxyribose phosphate unit. 4. DNA polymerase 1 inserts new nucleotide and DNA ligase seals it in. |
|
|
Term
| How does nucleotide-excision repair occur? |
|
Definition
| 1. 12 nucleotide fragment is cut and removed. 2. DNA is formed from DNA polymerase 1. 3. DNA ligase seals the new strip in. |
|
|
Term
| What is spontaneous deamination? |
|
Definition
| Spontaneous deamination is when, for example, cytosine loses its amine group spontaneously and forms uracil. This is repaired by AP endonuclease removing the faulty base and DNA pol 1 inserting a new one. |
|
|
Term
| How is RNA added in transcription? |
|
Definition
| RNA polymerase catalyzes the 3' hydroxyl to attack the 5' alpha phosphate. It uses Mg2+ to stabilize the intermediate. |
|
|
Term
| What subunits make up RNA polymerase and what do they do? |
|
Definition
| sigma=initiation of polymerase, alpha, beta, beta'=RNA polymerization |
|
|
Term
| To which end are new bases added on mRNA during polymerization? |
|
Definition
|
|
Term
|
Definition
| It is an untranscribed region of DNA that directs RNAP binding that is more 5' (on the coding strand) than the region being transcribed. |
|
|
Term
| What two experiments help determine the promotor? |
|
Definition
| DNA footprinting and isolation/purification |
|
|
Term
| How does the sequence of the promotor have any control over gene expression? |
|
Definition
| Changing the consensus sequence changes the affinity to which sigma can bind thereby controlling expression. |
|
|
Term
| What does the promotor do? |
|
Definition
| The promotor binds the DNA and the RNAP and unwinds a short piece of helix for RNAP to work. |
|
|
Term
| What consequences does the dissociation of the sigma subunit dissociating from RNAP? |
|
Definition
| It changes the affinity of the alpha-beta-beta' units for the DNA making it more processive. |
|
|
Term
| Why is there no proofreading in elongation?` |
|
Definition
| polymerase tolerates mistakes since proteins are transient species and are often quickly degraded. Since the protein code is degenerate, often times a mistake will code for the same exact protein. |
|
|
Term
| How is termination accomplished? |
|
Definition
| 1. The end of transcription encodes a hairpin followed by mulitple U's. This hairpin pushes the strand off of the RNAP and the poly-U tail only has 2 hydrogen bonds for easy breaking. 2. Rho-dependant termination is when Rho ATPase moves along the single stranded RNA intil it hits the RNAP causing the RNA to dissociate. |
|
|
Term
| What is the template strand, coding strand, antisense strand, sense strand? |
|
Definition
| The template is the DNA from which mRNA is formed. The coding strand is the reverse compliment of the template strand and is the same sequence as the mRNA. The sense strand is the coding srand and the antisense strand is the template strand. |
|
|
Term
| What base does uracil replace? |
|
Definition
|
|
Term
| What is the big difference between prokaryotes and eukaryotes with respect to initiation, elongation and termination? |
|
Definition
| There is no post trascriptional modifications of mRNA and it can immediately be transcribed. This is unlike eukaryotes since transcription and translation occur in two totally separate compartments. |
|
|
Term
| Why isn't post transcriptional processing required in prokaryotes? |
|
Definition
| rRNAs, tRNAs, etc are transcribed simultaneously and merely need to be cleaved. Usually an array of tRNAS are produced simultaneously. |
|
|
Term
| What does cis/trans mean specifically dealing with a promotor? |
|
Definition
| Cis means that the promotor is on the same strand of DNA as the gene. Trans is on the opposite strand of DNA. |
|
|
Term
| What things affect gene transcription? |
|
Definition
| 1. Promotor strength, 2. Proximity of promotor to genes transcribed, 3. presence/absence of repressors and activatos. |
|
|
Term
| What is transcribed when the Lac Operon is active? |
|
Definition
| Beta-galactosidase, lactose permease, acetyltransferase, lac repressor |
|
|
Term
| What does beta-galactosidase do? lactose permease? acetyltransferase? |
|
Definition
| Beta-galactosidase breaks the glycosidic bond of lactose, lactose permease is a transporter that brings lactose into the cell, acetyltransferase's role is currently unknown. |
|
|
Term
|
Definition
| The operator is a site on the DNA that is downstream of the promotor which can have repressors (LacI) bind to regulate expression. |
|
|
Term
| What molecule induces the lac operon? |
|
Definition
|
|
Term
|
Definition
| Pathogenicity island sequences- sequences of DNA encoding proteins required for infection. |
|
|
Term
| What do the three different eukaryotic RNA polymerases do? |
|
Definition
| Pol I- transcribes 18S, 5.8S and 28S rRNA, Pol II-transcribes mRNA and snRNA, Pol III- Transcribes tRNA and 5S rRNA |
|
|
Term
|
Definition
| Ribosomal RNAs that make up important parts of the ribosome. |
|
|
Term
| Why are svedbergs non-linear coefficients? |
|
Definition
| Since they are sedementation coefficients, just because 2 proteins may have unique sedementation properties, combining them does not yield a linear sedementation factor. |
|
|
Term
|
Definition
| The nucleolus is a cluster formed from the DNA template, RNA Pol I, and rRNA processing ribonucleoproteins. What consequences does this have on the cell? |
|
|
Term
| What are some of the characteristics of rRNA? |
|
Definition
| They are transcribed in tandem repeats and cleaved to form the 18S, 5.8S and 28S subunits. |
|
|
Term
| What 2 ways is Pol II transcription promoted? |
|
Definition
| Either a TATA box upstream of transcription start along with an enhancer unit acts as a promotor, or a downstream promotor element works along with an enhancer. Sometimes the promotors can be intragenic. What are the consequences of intragenic promotors? |
|
|
Term
| Describe the initiation of Pol II transcription: |
|
Definition
| 1. TBP binds to the TATA box, 2. TFIID binds to TBP, recognizes the promotor and bends the DNA. 3.TFIIA stabilizes TFIID binding to the DNA, 4. TFIIB helps determine the start site, 5. TFIIF interacts with non-template strand, 6. TFIIE recruits TFIIH, 7. TFIIH opens the promotor region and phosphorylates RNAPII |
|
|
Term
| What consequences does phosphorylation of the C-terminal doamin of Pol II have? |
|
Definition
| This phosphorylation allows binding of capping enzymes, splicing machinery and polyadenylation enzymes. This ensures that the enzymes and substrates find themselves in solution. |
|
|
Term
| What is the purpose/consequences of the 5' cap? |
|
Definition
| The unusual 5'-5' triphosphate contributes to the stability of the molecule since it repels phosphatases and nucleases. This also helps increase the chance for translation because the molecule is easier to recognize. Also, tRNAs and rRNAs are not capped. |
|
|
Term
| What exactly is the 5' cap? |
|
Definition
| The 5' cap is a methylated guanine attached to an adenine or guanine through a triphosphate linkage. |
|
|
Term
| Why does alternative splicing exist and what consequences does it have? |
|
Definition
| Alternative splicing is where various introns are removed in different tissues. This causes an array of different proteins to be made and can provide different functions for specific tissues and organs. |
|
|
Term
|
Definition
| An intron is a non-translated strip of RNA that is removed prior to translation. An exon is a region which is removed temporarily from a strip of RNA and is inserted back into the strand after splicing. |
|
|
Term
| How is splicing accomplished? |
|
Definition
| snRNAs also known as spliceosomes catalyze the removal of introns by facilitating the formation of the branch site. They also help orient the mRNA so that the branching can occur and the lariat can be created. |
|
|
Term
|
Definition
| poly(A)polymerase adds adenosine residues on the terminal end of mRNA (3' end) by use of ATP and by reading the cleavage signal (AAUAAA). |
|
|
Term
|
Definition
| 1. The 2' hydroxyl at the branch point attacks the phosphodiester bond at the 3' end of the exon. 2. 3' hydroxyl of the exon attacks the 5' phosphate at the 5' end of the next exon. |
|
|
Term
| What residue is most common at the branch point in splicing? |
|
Definition
| A. It is highly conserved as well as multiple purine and pyrimidine residues in that region. |
|
|
Term
| What are the three lac operon genes that are expressed? |
|
Definition
| z, y, a as well as the inhibitor |
|
|
Term
| What is the -35 sequence associated with sigma 70? -10? |
|
Definition
| -35=5'TTGACA3' and -10=5'TATAAT3' |
|
|
Term
| What happens when mRNA exits the nucleus? |
|
Definition
| PABP1 (poly-adenylated binding protein 1) and elFs (Elongation factors) proteins bind the mRNA and interact with one another to form a circular structure. |
|
|
Term
| Poly-adenylation occurs on which end? 5' or 3'? |
|
Definition
|
|
Term
| What happens to tRNA after it is transcribed? |
|
Definition
| It is spliced, cleaved and modified with bases such as inosine, pseudouridine, 5-methylcytidine, dihydrouridine, N-acetylcytidine |
|
|
Term
| Why is tRNA modified so much? |
|
Definition
| It does 2 things: 1. It allows for a unique structure, 2. It allows for interaction with tRNA synthetases and the ribosome. |
|
|
Term
| What is the function of tRNA? |
|
Definition
| It acts as an adaptor molecule to bring amino acids to the mRNA to make protein. |
|
|
Term
|
Definition
| It is an enzyme that combines NTPs to make short RNAs (used to make strips of RNA made out of only one base) |
|
|
Term
| How was the genetic code determined? |
|
Definition
| A tRNA binding assay was used where they manipulated 3-nucleotide long strips of RNA along with the ribosome and attached them to a filter. By washing tRNAs over them along with the amino acids, only the ones that coded for that amino acid stuck. |
|
|
Term
| What are the 2 most important positions in the codon? |
|
Definition
| The first two going 5' to 3'. The last position is called the wobble position because it doesn't have as strong of an interaction with the mRNA due to the structure of the tRNA. |
|
|
Term
| What is the genetic code with specific regards to the words degenerate and redundant? |
|
Definition
| The genetic code is NOT redundant (as in one 3 base code ONLY codes for ONE amino acid) and the genetic code is degenerate since multiple codons can code for the SAME amino acid. |
|
|
Term
| What are the permiscuous 5' bases of tRNA? |
|
Definition
| Inosine= U, C or A. Guanine=U or C. Uracil= A or G. |
|
|
Term
| What is aminoacyl tRNA synthetase and what does it do? |
|
Definition
| Aminoacyl tRNA synthetase is an enzyme that adds the correct amino acid to the correct tRNA |
|
|
Term
| How is the aminoacyl-tRNA formed? |
|
Definition
| 1. Amino acid binds to ATP to make aminoacyl-AMP. 2. Aminoacyl-AMP binds to the 3' -OH of tRNA to form aminoacyl-tRNA and AMP |
|
|
Term
| How come only some aminoacyl-tRNA synthetase enzymes have editing sites? |
|
Definition
| Since you need a different aminoacyl-tRNA synthetase for each amino acid, some don't require an editing site because the amino acid that they bind is so highly unique. |
|
|
Term
| What does aminoacyl tRNA synthetase interact with? |
|
Definition
| The amino acid and the anticodon site. |
|
|
Term
| Name the functions of the ribosome: |
|
Definition
| 1. Recognise tRNA, 2. Peptide bond formation, 3. Translocation of the formed protein |
|
|
Term
| What are svedbergs and why are they "non-linear"? |
|
Definition
| Svedbergs are units for a specific sedementation coefficient. Different molecules have different sedementation coefficients and in solution, if they interact they further change this sedementation factor in a non-linear fashon. |
|
|
Term
| What are the 3 sites on the ribosome and what do they do? |
|
Definition
| They are the E, P and A sites. A: aminoacyl site where tRNA enters, P: Peptidyl site (where polypeptide forms), E: Exit (tRNA exits through this site after peptide bond is formed. |
|
|
Term
| Name the purines and pyrimidines: |
|
Definition
| Purines: A, G. Pyrimidines: C, T. |
|
|
Term
| What are the steps for ribosomal initiation? |
|
Definition
| 1. Initiation factors facilitate formation of the initiation complexes, 2. f-Met is the N-terminal AA and is the first to enter the ribosome, 3. Initiation factors dissociate to allow elongation. |
|
|
Term
| What do initiation factors I, II and III do for ribosomal initiation? |
|
Definition
| I marks the A site of the ribosome and facilitates binding of the mRNA. II recognizes f-Met tRNA. III prevents large and small subunit reassociation so that the ribosome is open. |
|
|
Term
| What is Ef-Tu and what does it do? |
|
Definition
| Ef-Tu binds GTP and aminoacyl-tRNAs, brings them to the A site of the ribosome and when it matches the anticodon with the codon of the mRNA, GTP is hydrolyzed and Ef-Tu dissocuates. It prevents peptide bond formation in case the tRNA does not match properly with the codon. |
|
|
Term
| What is EF-G and what does it do?> |
|
Definition
| Upon peptide bond formation, EF-G comes into the A site and moves eveything over to the next site in the chain. This requires ATP hydrolysis. |
|
|
Term
| Name the steps for elongation: |
|
Definition
| 1. EF-Tu brings aminoacyl-tRNA to the A site. 2. GTP is hydrolyzed and EF-Tu releases the aminoacyl-tRNA. 3. The 23S rRNA catyalyzes the peptide bond formation. 4. EF-G facilitates translocation of the aminoacyl-tRNA to the P site. 5. tRNA exits via the E site. |
|
|
Term
| What do the stop codons code for? |
|
Definition
| Release factors (RFs) that mediate the termination of protein synthesis. |
|
|
Term
| Promotor element is on which strand? |
|
Definition
|
|
Term
| What is the Shine-Delgarno sequence? |
|
Definition
|
|
