Summary
Summary Mammalian cell biology
- Course
- Institution
Mammalian cell biology
[Show more]
Seller
Follow
annerixtvanderwal
Content preview
Mammalian cell biology lecture 1 31-8Species: closely related organisms that are similar and capable of interbreeding and
producing fertile offspring.
Realm -> domains
Lumen -> vaatholte
Metabolites dissolves in water
Lipids dissolves in fat
Cytoplasm -> all contents of a cell exept cell membrane and nucleus
Cytosol -> Cytoplasm without organelles
Mitosis is symmetric cell dividsion and Meiosis is asymmetric cell division
Transcription
Translation
DNA -> AGCT(Thymine) Double-stranded
RNA -> AGCU(Uracil) Single-stranded
RNA-splicing introns and exons (introns are removed from protein-coding exons)
Isoforms are different protiens that derive form the same gene.
Triplet -> codon
Stop and start codon
9 essential aminoacids
Primary-, Secundary- tertiary- and Quatenary structure
Virus are not living organisms, it is a membrane that is packed with proteins that hijack host
ribosomes and proteins for replications. That way they can replicate quickly.
Peptide bond/amide bond formed by de-hydrolysis(condensation)
Cis- & transbonds
Alpha-helix & Beta-sheets
Phosphorylation activates or deactivates protiens
Ubiquitinations
-small protein (76 amino acids)
- multiple conjucated to lysine of target protein
- marks protein for: degradation by proteasome/ endocytosis
Proteasome is a large barrel-shaped protein structure in cytosol that degrades protein.
Transporters
Channels: Passive transport (holes)
Secondary transporters: use gradient of other molecules (diffusion and osmosis)
ATP-binding cassette (ABC) transporter: ATP-couples active transport
Sugar metabolism consists of Glycolysis(cytosol) and Oxidative respiration(mitochondria)
1
,CO2 cycle by photosynthesis and respiration, what photosynthesis creates is used with
respiration.
Metabolism: catabolic (produces energy) and anabolic (consumes energy)
ATP is the main energy storage of cells.
Mammalian cell biology lecture 2 7-9
Rough ER has punctuated structured membrane. The ribosomes are on the membrane of the
ER.
Co- translational insertion in rough ER.
SRP binds to the signal sequence and stops the process of translation. It pulls the ribosome
to the Translocon. It binds to the ER. There the signal sequence remains in the ER and then
the translation continues.
Binding immunoglobulin protein (BiP) helps protein translocation and folding. BiP prevents
premature folding.
Trans-membrane proteins
- Type 1 (N-terminus in ER lumen)
- Type 2 (C-terminus in ER lumen)
- Type 3 (N-terminal (signal-anchor) in membrane)
- Tail-anchored (C-terminus in membrane)
- Type 4 has multiple transmembrane segments
N-terminus has a primary aiming the protein starts with an N-terminus (NH3+) in a neutral
enviourment.
C-terminus has a carboxylic group the protein stops with a C-terminus (COO-)
Hydrophobic inside the membrane.
Stop-transfer anchor (STA)
- Hydrophobic trans-membrane segment
- Prevents translocation over membrane
- Lateral opening of Sex61 translocon
- Will become transmembrane segment
Signal anchor (SA)
- Translocation after synthesis
- Targeting via SRP
- Positive charge determines orientation
- Are not cleaved of
Type 2 has no a signal sequence and there is no cleavage of the signal.
Type 1 membrane proteins have a signal sequence type 3 does not.
Positive inside(cytosol) rule
2
, - Charge of residues next to signal anchor determines orientation
- Largest positive charge in cytosol.
Signal anchors are similar to signal sequences but are not cleaved of.
Type 4 is a combination of type 1,2 & 3. Combination of STA and SA. Has multiple
transmembrane regiouns
SA is made before it is inserted into the membrane
If the chargers are at the c terminus it is type 3 if it is at the n terminus it is type 2.
Polar is hydrophilic.
GPI-anchored are always type 1 proteins.
Post-translational insertion into the mitochondria. Some proteins are transcribed and
translated within mitochondria. They have their own (small) chromosome, this codes for 13
proteins.
Chaprerone Hsc70 binds in a ATP-dependent manner to keep the protein unfolded to get
into the mitochondria.
Tom: transporter of the outer membrane
Tim: transporter of the inner membrane
1. Dissociation of cytosolic Hsc70 consumes ATP
2. Translocation of cationic signal sequence through TIM mediated by membrane
potential
3. Dissociation of matrix Hsc70 consumes ATP
Post-translational insertion into nucleus meaning the protein is already fully formed. Into the
nucleus the protein is folded which is different to the mitochondria.
Karyopherins
Small-GTPase are like molecular switches which can be on/off switch
Ran-GDP state is cytosol by Ran-GAP
Ran -GTP state in nucleus by Ran-GEF
Mammalian cell biology lecture 3 14-9
Major groove & minor groove
10 base pairs make one helix part = 3,4 nm = 1 turn
DNA is righthanded tumb points in the direct of movement
Sugar piece and phosphate (5 prime end 5’)
- C-G 3 hydrogen bonds
- A-T 2 hydrogen bonds
3
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller annerixtvanderwal. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $5.97. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
64438 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now