Endoplasmic Reticulum

Created by jalbe860 

Upgrade to
remove ads

Detailed overview of Rough and Smooth ER and associated functions

Cisternae

Name of flattened sacs which make up the membrane of the ER.

ER Lumen

also known as cisternal space, interior of ER membrane.

Smooth ER

Organelle associated with drug detoxification.

Hydroxylation

The process of adding a hydroxyl group to a non-polar molecule so that it becomes more soluble in water and is excreted from the organism. (Smooth ER)

Glucose-6 Phosphatase

Main enzyme of glucose metabolism found in smooth ER.

Liver

Organ used for glucose regulation and storage as glycogen.

Sarcoplasmic reticulum

Organelle specialized for Ca 2+ storage in muscle cells.

Rough ER

Continuous with outer nuclear membrane.

Smooth ER

Organelle associated with carbohydrate metabolism.

Smooth ER

Section of ER used in calcium storage.

Rough ER

Organelle associated with protein synthesis.

Translocon

Protein in rough ER used for co-translation of proteins into the cisternal space(lumen).

Signal peptide sequence

Protein sequence which labels proteins for import into ER

Stop transfer sequence

Protein sequence which labels proteins for integration into membrane.

Signal peptidase

Enzyme which cleaves signal peptide sequence from polypeptide chain as it enters the lumen.

Rough ER

Site of co-translational and post-translational modifications.

Protein disulfide isomerase

Enzyme which catalyzes the formation and breakdown of disulfide bonds.

Rough ER

Site of protein folding.

40S

Size of small eukaryotic ribosomal subunit.

60S

Size of large eukaryotic ribosomal subunit.

30S

Size of small prokaryotic ribosomal subunit.

50S

Size of large prokaryotic ribosomal subunit.

80S

Size of eukaryotic ribosome.

70S

Size of prokaryotic ribosome.

Aminoacyl site

Site of tRNA arrival in ribosomes, also known as A site.

Peptidyl site

Site of peptide bond formation in ribosomes, also known as P site.

Exit site

Site where tRNA leaves the ribosome.

mRNA binding site

Site where mRNA binds to ribosome.

Aminoacyl tRNA

A tRNA with it's attached amino acid.

Anticodon

Three nucleotide sequence complementary to a codon in tRNA.

Francis Crick

Who proposed the wobble hypothesis.

Inosine

Unusual nucleotide found more commonly in tRNA which can pair with U, C, and A.

Aminoacyl-tRNA synthase

Enzyme used to link the proper amino acid to the proper tRNA.

Leader

Segment of mRNA not translated found before the start codon.

Trailer

Segment of mRNA not translated found after the stop codon.

Polygenic

Adjective used to describe mRNA which can code for several proteins, found in Prokaryotes.

5' to 3'

Direction ribosome travels on mRNA.

Initiation

First step of protein synthesis where ribosome binds to mRNA.

Elongation

Second step of protein synthesis where amino acids are added to a growing polypeptide chain.

Termination

Third step of protein synthesis where polypeptide and mRNA are released from the ribosome.

1

IF1, IF2, and IF3 bind to the 30S ribosomal subunit and GTP binds to IF2. (Enter numerical order of this step in prokaryotic translation)

2

mRNA and tRNA-Methionine bind to 30S ribosomal subunuit IF1 and IF3 are released.(Enter numerical order of this step in prokaryotic protein synthesis.)

Shine-Dalgarno

Name of 3-9 purine nucleotides found upstream of start codon in mRNA. This sequence binds part of the 30S ribosomal subunit that has a pyrimidine rich rRNA segment.

N-formylmethionine

First amino acid integrated into prokaryotic polypeptides.

3

GTP hydrolysis joins the 50S and 30S ribosomal subunits. IF2 is released and translation begins.(Enter numerical order of this step in prokaryotic protein synthesis.)

1

40S ribosomal subunit is complexed with eIF3 and eIF1A. eIF2-GTP binds with tRNA-met and binds to 40S subunit. This complex then binds to 5' end of mRNA.(Enter numerical order of this step in eukaryotic protein synthesis.)

2

eIF4 disassembles secondary structure found at the capped 5' end of the mRNA. This finalizes the 40S initiation complex. (Enter numerical order of this step in eukaryotic protein synthesis.)

3

The 40S initiation complex slides along the mRNA until the Kozak sequence and start codon are found. There the 60S ribosomal subunit joins and translation begins.(Enter numerical order of this step in eukaryotic protein synthesis.)

Kozak sequence

5'-ACCAUGG-3' Name of this sequence which 40S initiation complex searches for to bind 60S ribosomal subunit and begin translation.

EF-Tu

Elongation factor needed to transport aminoacyl tRNA to A site of ribosome in prokaryotes. Carries two GTP molecules.

rRNA

Molecule in ribosome responsible for what was mistaken as peptidyl transferase activity.

Ribozyme

Name of enzyme which is made entirely out of RNA.

EF-G-GTP

Elongation factor needed for translocation of tRNA from sites A and P to sites E and P in prokayrotes, bound to GTP.

Hydrolytic cleavage

Type of reaction which occurs when a release factor terminates eukaryotic protein synthesis.

BiP

Other name for heat shock protein 70(Hsp70)

Heat shock proteins

Class of molecular chaperones which assist in folding proteins into the correct conformation or refolding misfolded proteins.

Ubiquitin

The molecule which mutated or misfolded proteins are tagged with for degradation in the cytoplasm after they are deglycosylated.

Ubiquitinylation

The process of degrading a misfolded protien after tagging it with ubiquitin.

Apoptosis

Aggregates of misfolded proteins can sometimes form which could lead to.

tau MAP

Name of polymerized protein which forms intracellular tangles in alzheimer's disease.

Prions

Name of replicating misfolded proteins.

Nonsense mutation

A mutation which changes an amino acid coding codon to a stop codon.

Protein splicing

Removal of segments of a polypeptide in post-translational modification.

Intein

Name of removed segment from a spliced protein.

Exteins

Name of segments of polypeptide chains which are spliced together.

Co-translational import

Process of polypeptide synthesis into the Rough ER.

Signal recognition particle

Protein which binds to signal peptide, ribosome, and receptor on ER. Protein blocks translation of mRNA until docked at rough ER.

BiP

Molecular chaperone of the rough ER which binds to hydrophobic regions of unfolded polypeptide to stabilize molecule.

KDEL

Name of protein sequence which targets proteins to ER related organelles.

Glycosylation

Name of the addition or modification of sugar side-chains to newly folded proteins in the rough ER.

High-mannose core

Type of core found in sugar molecules added to proteins.

Golgi complex

Where soluble proteins produced in the Rough ER are sent.

Start transfer sequence

Protein sequence which is bound by the signal recognition particle to be sent for another pass through the membrane.

SKL

Protein sequence which targets proteins to peroxisomes.

Transit sequence

Sequence used to target polypeptides to the chloroplast and mitochondria.

4

How many compartments are found in mitochondria?(Enter a number)

6

How many compartments are found in chloroplasts.(Enter a number)

N-linked glycosylation

The addition of a specific oligosaccharide to asparagine as part of post translational modification.

O-linked glycosylation

The addition of a specific oligosaccharide to the hydroxyl groups of serine or threonine as part of post translational modification.

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set