Master class Biomolecular Sciences
Part 1: Molecular Cell Biology.
4 September 2007
Paul van Bergen en Henegouwen
Master class Biomolecular Sciences
Part 1: Molecular Cell Biology. Sept-Nov 08
04-09-08: Paul van Bergen en Henegouwen.
Mechanisms of clathrin-independent endocytosis
11-09-08: Willem Stoorvogel.
Endocytosis and MHC classII
18-09-08: X-track symposium
25-09-08: Ger Strous.
Ubiquitination and endocytosis
02-10-08: Catherine Rabouille (coordinator).
Classical and unconventional secretion
09-10-08:Madelon Maurice.
Wnt pathway and membrane traffic
16-10-08: ABC-seminar I&I +IB Aio dag
23-10-08: Fulvio Reggiori.
30-10-08: Bernd Helms.
06-11-08: Exam
Autophagy
Lipid droplet biogenesis
Non clathrin mediated
endocytosis
Classical
secretion
unconventional
Before I start, few statements:
http://www.bio.uu.nl/BiomolecularSciences/
- The course is compulsary. If you have no choice of missing ONE class,
contact the teacher and the coordinator by email (on website)
- Each lecture will be posted on the website few days after each class
- Article presentation. Each of you will study one article per block in a group of 2-34 persons. Prepare the article as well as possible while contacting the
teacher at least one week in advance. When you meet, the
preparation should be done and you come for questions and for
sorting out details.
- Read the article: Download the article from the web for the colour pictures
before coming to the course using the guidelines, your brain and
your knowledge. The more you have thought of it, the better the
discussion.
- Exam. There will be 7 questions related to the 7 articles presented, hence
the above. The more you participate, the easiest.
- Switch off your mobile. No ringing, no SMS.
Mechanisms of clathrinindependent internalization
Paul van Bergen en Henegouwen
Endocytosis: what’s the problem?
bending
fission
Five ways to bend a membrane
Clathrin-dependent internalization
Clathrin-coated and vesicles:
Ultrathin section of plastic-embedded material
Clathrin-coated pits and vesicles by EM
Replica of freeze-dried plasma membranes
Clathrin-coated vesicles:
Replica of freeze-dried plasma membranes
Clathrin: Heavy- and light chains
Clathrin makes a network
How clathrin is bending
Adaptor Protein-2 complex, AP-2
a-adaptin
100 kDa
Ear
Hinge
Trunk
a
m2
s2
b2
b-adaptin
50 kDa
17 kDa
There are different AP-complexes
on different sites in the cell
g
AP-1
AP-2
AP-3
m1
m2
m3
s1
b1
Golgi-complex
a
b
2
s2
Plasma membrane
d
s3
b3
Golgi-complex
Protein/protein interactions control CCV formation
Eps15
I
II
EHs
COIL
III
DPF/UIM
NPF
DPF
LfxfD/E
DPW
AP-2
Epsin
a
Yxxf
m2
s2
b2
Lipids
Clathrin
LL
Receptor
PIP2
Receptor
The netwerk forms a bal:
Electron tomography of a coated vesicle
a adaptin
s chain
Clathrin triskelion
b adaptin
m chain
Adaptor protein
(AP2) complex
©John Wiley &Sons,Inc
Smith et al. (1998) EMBO J. 17, 4943
Overview of clathrin structures
Marsh and McMahon (1999) Science 285, 215-220
From bending to fission
Dynamin, a GTPase involved in fission
PIP2
Amphiphysin
Dynamin is forming a ring around the neck
Effect of pure dynamin on lipid vesicles
Moleculen involved in the whole process
PIPK
AP2
Clathrin
Eps15
Intersectin
Amphiphysin
Epsin
Dynamin
Endophilin
Membrane curvature generation
Mogelijke rol van actine filamenten
Moleculen betrokken bij CCV vorming
PIPK
AP2
Clathrin
Eps15
Intersectin
Amphiphysin
Epsin
Actin
Synaptojanin
Auxilin
Hsc70
Dynamin
Endophilin
Membrane curvature generation
Overview of all interactions
EGFR internalization via a non-coated pathway!
Is the alternative route visible?
Caveolae
Caveolin
Caveolar internalization starting from cholesterol-rich domains
Trafficking of Caveolae
Internalization of large items: Phagocytosis
Overview of different internalization routes
Properties of different CI-routes
Classification of internalization routes
Questions
What does the bending?
What does the fission?
Interleukin-2 receptor complex
IL-2R internalization is Clathrin-independent
clathrin-inhibition by ΔEps15
IL-2R internalization is Dynamin-dependent
Dynamin-inhibition by Dyn-K44
TfR
wt
K44A
IL-2R is present in the Detergent Resistant Membrane
(DRM) fraction
Overview of different internalization routes