100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Summary MBOC Chapter 13 - Intracellular membrane traffic $3.20
Add to cart

Summary

Summary MBOC Chapter 13 - Intracellular membrane traffic

 34 views  2 purchases
  • Course
  • Institution
  • Book

Summary of Chapter 13 of Molecular Biology of the Cell

Preview 2 out of 5  pages

  • No
  • 13
  • July 2, 2021
  • 5
  • 2020/2021
  • Summary
avatar-seller
Chapter 13: Intracellular Membrane Traffic
 exocytosis – transport vesicle fuses with the plasma membrane
 endocytosis – plasma membrane patch is internalised, forming a transport vesicle –
content derives from extracellular space
o endosomes = internal
compartments
 lumen = interior space of each membrane-
enclosed compartment
o proteins can travel in this space
without having to cross a membrane
 transport vesicles = forms of containers
o bud off from one membrane and
fuse with another, carrying membrane components and soluble luminal
molecules, which are referred to as cargo
o donor compartment and target compartment
o must be selective
 secretory pathway – ER  Golgi apparatus
 endocytic pathway – leads inward from the plasma membrane
 retrieval transport  transport in opposite direction; return to ER

The molecular mechanisms of membrane transport and the maintenance of
compartmental diversity
 coated vesicles  specialized, coated regions of membranes; have a distinctive
cage of proteins covering their cytosolic surface
o 1) concentrates specific membrane proteins in a specialised patch, which then
gives rise to the vesicle membrane
o 2) shapes vesicle
 Three well-characterised types of
coated vesicles, distinguished by
their major coat proteins:
o 1) clathrin-coated –
mediate transport form the
Golgi apparatus and from
the plasma membrane
o 2) COPI-coated – mediate
transport from the ER and
from the Golgi cisternae
 bud off from Golgi
apparatus
o 3) COPII-coated – mediate transport from the ER and from the Golgi cisternae
 bud off from ER
 Adaptor proteins select cargo into clathrin-coated vesicles

Transport from the ER through the Golgi apparatus
 Golgi apparatus = Golgi complex  major site of carbohydrate synthesis, as well
as a sorting and dispatching station for products of the ER
 Proteins leave the ER at ER exit sites -whose membrane lacks bound ribosomes
o Proteins leave the ER in COPII-coated transport vesicles
 Only proteins that are properly folded and assembled can leave the ER
o otherwise: chaperones / proteasomes

,  Vesicular tubular clusters mediate
transport from the ER to the Golgi
apparatus
o heterotypic fusion
o homotypic fusion
 retrieval pathway  carrying back ER
resident proteins that have escaped,
as well as proteins such as cargo
receptors and SNAREs that
participated in the ER budding and
vesicle fusion reactions
o uses ER retrieval signals
 The retrieval pathway to the ER uses sorting signals: KDEL
o on C-terminus!
o Lys-Asp-Glu-Leu
o KDEL receptor travel between ER and Golgi apparatus
 can interact both with COPII coat and COPI coat
 has high-affinity for KDEL sequence in vesicular tubular clusters and
the Golgi apparatus
 has low-affinity for KDEL sequence in ER




 Golgi apparatus
o cisternae  membrane-
enclosed compartments
o cis face = entry face  cis
Golgi network (CGN)
o trans face = exit face 
trans Golgi network (TGN)
o N-linked oligosaccharide
serve to help proteins fold
and to help transport
misfolded proteins to the
cytosol for degradation in
proteasomes
  controlling quality
of proteins exiting from the ER
 are processes in the Golgi apparatus
 Two broad classes of N-linked oligosaccharides:
o complex oligosaccharides

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

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

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

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 esmstegeman. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $3.20. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

53068 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$3.20  2x  sold
  • (0)
Add to cart
Added