Exam 22: Protein Synthesis, posttranslational Modification, and Transport

Does the figure below represent a prokaryotic or eukaryotic translation system? Describe the clues used to form a decision.

Below are seven examples of sequences found in E.coli.Differentiate between the underlined and bolded sequences.Explain where each would ultimately be located in the 70S initiation complex and what types of interactions are required to achieve these locations.

How was the selectivity of the nitrocellulose filter essential in the Nirenberg-Leder experiment,which was able to assign triplet codons to specific amino acids?

What is the identity of the protein labeled with the question mark in the eukaryotic preinitiation complex shown below?

An experimental prep is able to separate the following membrane fractions: nuclear membrane,Golgi apparatus membrane,transport vesicle membrane,and mitochondrial membrane.The membrane fractions can then be analyzed via Western blotting for the presence of specific proteins.Which fraction would indicate the presence of t-SNAREs?

Choose the sequence that is MOST likely to be modified with the fatty acid palmitoylate in the ER.(The … represents additional amino acids N-terminal or C-terminal to those shown.)

Release factor hydrolyzes GTP during the __________ step of translation.

In the ER,prenylation can occur.Prenylation is the attachment of an isoprenoid group to a __________ residue via a(n)__________.

In an iteration of the Nirenberg-Leder experiment to assign triplet codons to specific amino acids,radioactively labeled aminoacyl-tRNA with the anticodon of CUG was used.The radioactivity was retained on the filter at the end of the experiment.Which mRNA was used in this iteration of the experiment?

An inhibitor of __________ would specifically prohibit the release of Ran from importin.

Which protein would initially have been translated on free ribosomes?

Relate the importance of the binding of Ran to importin to its role in nuclear import.

Which base location in the figure below is LEAST discriminating in the bases that it can pair with as described by the wobble hypothesis?

What region of the amino acid below would become covalently attached to a tRNA?

Both prokaryotes and eukaryotes recognize __________ as a start codon.

Eukaryotes are directed to begin scanning the mRNA for the start codon based on binding of the

Place the following steps in the initiation phase in a prokaryote in their proper order. A.mRNA binds to the complex. B.GTP is hydrolyzed. C.IF1,IF2,and IF3 bind the 30S subunit.

Contrast both the structure and function of a prokaryotic initiator tRNA with a prokaryotic Met-tRNA^Met.

Inosine is formed through a

In yeast,the number of tRNA genes is __________ the number of __________.