genetics chapter 13

translation and proteins

ribosome

ribosome

Called the ‘work bench’, the protien synthesis machines, are made of protein and rRNA, one of the most abundant organelles in cell

bigger

In eukaryotes the ribosomes are _____ and have bigger subunits (70s in prok, 80s in euk)

a-site

_-___ where the mRNA first comes into the ribosome. not where the AUG first is tho.

p-site

_-___ where the AUG is first, where the peptide chain is made through copy/pasting

tRNA

bind to mRNA via anticodon, and bind to amino acid via acceptor stem (3’ end!)

May have modified bases (inosine in first position of anticodon, binds w 3rd position of codon, causes wobble)

inosine

A modified base of tRNA, in first position of anticodon, binds w 3rd position of codon, causes wobble

floating

the anticodon of the tRNA is ‘_____’ meaning it does not interact with the rest of the tRNA, it is waiting to be used w codon on mRNA

aminoacyl

_____ tRNA synthetases- specific for each amino acid. connects the tRNA w the correct amino acid on 3’ end.

CAA

What is the attachment site for the amino acid on the tRNA sequence?

small

the mRNA first binds to the _____ subunit before the initiator tRNA binds to the mRNA

if-3

in prokaryotes, what is the initiator factor that blocks the large subunit from binding to the small subunit.

shine-delgaro

What is the sequence of upstream sequence called which locates where the AUG reading frame should start? like promoter

IF-1

Which initiator factor blocks the A-site so that the AUG fills the p-site

IF-2

which initiator works w GTP to bind w mRNA and the charged tRNA?

fmet- tRNA^fmet

What is the tRNA called which binds w AUG in PROKs?

30s

The small ribosome and mRNA are collectively called the ____ initiation complex

70s

The __ initiation complex is the whole ribosome and mRNA after if-3 dissociates

charged

the first word before tRNA tells if it is _____ or not

loaded

The superscript above tRNA shows what it is supposed to be ______ with.

initiator

All tRNA bind to A-site first (except for ____ tRNA)

peptide

What type of bond is formed between amino acids after moving from A to P?

hydrolysis

Translocation requires EF-G and GTP _______

recharged

tRNA can be ______ and used again after exiting the ribosome

release factors

When a stop codon is in the A-site, ___ _____ bind to the codon which cause the polypeptide chain to be released

prokaryotes

In _______, there is simultaneous translation and transcription

fmet

In proks, they use ____ instead of usual met for initation

tRNAi

In euks, instead of tRNA they use _____ for initiation

longer

in eukaryotes the mRNA lasts _____ bc of the cap and poly a tail

eIF4E

What is the cap binding protein for the 5’ end?

eIF4G

What is the cap binding protein for the 3’ end (poly-A)

kozak

in eukaryotes, the _____ sequence surrounds the starting starting AUG

reused

since the mRNA makes a closed loop in eukaryotes, the ribosomes get _____ (and the tRNA get re-charged)

must

In prokaryotes the mRNA ___ have a SHINE-Delgarno, or it cannot replicate (not same w Kozak and Eukaryotes)

Garrod, Bateson

Two men who suggested genes encoded enzymes (the relationship between genotype and proteins)

beadle, tatum

used bread mold to conclude that for every gene is one enzyme, found through mutations and minimal media

polypeptide

Later after Beadle and Tatum, people found that one gene is responsible for one ________

enzymes

nearly all _____ are proteins but not all proteins are ____________

sickle cell

Through ___ ___ anemia, research found that the mutation was due to one single polypeptide mutation

primary

the first protein structure, just amino acid sequence

secondary

The interactions between amino acids, folds and twists of polypeptide (alpha helix or beta pleated sheets)

alpha helix

a secondary structure of proteins that looks like a noodle with different hydrogen bonds between amino acids not next to each other

beta pleated sheets

a secondary structure of proteins that looks like a folded piece of paper

amino

the beginning of an polypeptide has a _____ group to the left

carboxyl

The end of a polypeptide has a ____ group to the right

radical

The bottom of a polypeptide as a ______ group which controls the polypeptide’s characteristics

hydrophobic

The non polar group has polypeptides like alanine and methionine in it and is _______

water

when forming a polypeptide bond, there is a exit of ____ between a carboxyl and amino group

essential

In proteins, structure is _______

tertiary

the third protein structure, interaction of secondary structures

quaternary

the fourth protein structure, interaction of two or more polypeptides (ex. holoenzyme like DNA3)

active

an _____ site is a place where the protein ‘grabs’ or catches a substrate to preform a reaction on it and eventually lets it go

molecular chaperone

one post-translational modifier is a ____ ______ which helps the protein fold in the correct way after it is released from the ribosome, or corrects it’s folding.

signal sequence

Another post-translational modifier which gets the protein where it needs to go but not important in sequence function. gets cut off

clean cut

Mutations are not easily found for each gene because it is not ____ ____. This is because the protein interacts and has other jobs so it is difficult to see an exact phenotypic consequence for a mutation.

antibiotics

can target differences between eukaryotes and prokaryotes. such as blocking an A-site in prokaryotic cells so translation cannot occur

prions

an infectious protein.

stanley prusiner

the man who discovered the reason for Scrapie in Sheep (prions)

misfolded

Prions are ______ proteins that replicate by changing normal proteins and aggregating (Mad Cow)

hereditary

prions can be _______ due to a mutation where the misfolding is more ‘stable’

exception

prions are an ______ to central dogma