steps of translation

In translation initiation where do the subunits first bind to?

The mRNA & tRNA before the large subunit binds

True of false : does translation initiation require energy ?

True

During translation elongation where are amino acids added one by one to ?

The previous amino acid at the C - terminus of the growing chain

How does a polypeptide chain grow?

From it N to C terminus

Where does a stop codon need to reach for release factor proteins to bind

The ribosomes A site during translation termination

During termination translations what happens to the polypeptide chain?

It is cleaved and released from the tRNA & the translation assembly comes apart

The tRNA for which amino acid is tge first to enter the ribosome?

Methionine

What is the first event to take place in translation ?

The small subunit of the ribosome recognizes and attaches to the mRNA

When is a peptide bond formed during the process of translation?

During the elongation phase, just after a tRNA charged with the next amino acid binds to the A site

What is the function of the release factor during translation?

It binds to the stop codon in the A site in place of a tRNA

When do the small ribosomal subunits bind to mRNA?

Before the large subunit joins

When does the large unit assemble?

Only after the initiation complex is formed

True or False: Each tRNA has a specific anticodon that pairs with a complementary mRNA codon ensuring accurate amino acid incorporation

True

During elongation, how does the ribosome ensure accurate translation of mRNA?

By reading mRNA codons from 5’ to 3’ end and matching them with complementary tRNA anticodons

During initiation, how does the small ribosomal subunit contribute to the assembly of the translation complex?

By binding to mRNA to position the start codon in the ribosome

What is post translational modifications?

When covalent alterations controlling protein activity after translation

What are some common types of PTM?

• methylation

• Acetylation

• Ubiquitination

• Phosphorylation

Glycosylation is the post translation addition of ________ to the protein.

A carbohydrate

Which is a reversible form of post translational modification which can activate or deactivate a protein depending on the protein which is being modified?

Phosphorylation

Methylation typically occurs on which type of protein residue?

Lysine and arginine residues

An inhibitor of acetylation is introduced to a cell culture. What potential impact might this have on histone proteins?

Histone proteins may bind more tightly to DNA, potentially reducing gene expression