vesicular transport dr. med. habil. kőhidai lászló assoc. professor depertment of genetics, cell-...
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VesicularVesicular transport transport
Dr. med. habil. Kőhidai LászlóDr. med. habil. Kőhidai LászlóAssoc. ProfessorAssoc. Professor
Depertment of Genetics, Cell- and ImmunoibiologyDepertment of Genetics, Cell- and Immunoibiology Semmelwesi UniversitySemmelwesi University
2008. 2008.
IntracellulIntracellularar ve vessiicularcular tratransportnsport
Communication Communication – intracellular; – intracellular;
- cell-environment- cell-environment
Membrane system Membrane system Uptake of substances and transport to the Uptake of substances and transport to the
place of digestion (lysosomes) - place of digestion (lysosomes) - endocendocytosisytosis Transport of proteins between ER-Golgi and Transport of proteins between ER-Golgi and
to the surface membrane - to the surface membrane - exocexocitózisitózis
Main pathways of vesicular transportMain pathways of vesicular transport
IntracellulIntracellularar ve vessiicculularar tratransportnsport
Bidirectional, transport between Bidirectional, transport between compartment is balancedcompartment is balanced
Continous recyclicling of membrane Continous recyclicling of membrane proteins proteins
Pathway of bPathway of biosiosynthetic-ynthetic-and secretory processesand secretory processes
EEndocndocytosisytosis
RecyclingRecycling
Transport vesicles
Membrane bounded vesicles filled with Membrane bounded vesicles filled with different cargosdifferent cargos•SecretionSecretion
•Lysosomal enzymesLysosomal enzymes
•Components of surface membrane and the ECMComponents of surface membrane and the ECM
Direction of transport is determined by the Direction of transport is determined by the components of the membrane see: donor and components of the membrane see: donor and target compartmentstarget compartments
Molecular bases of vesicular transport
Biosynthetic-secretory and endocytotic Biosynthetic-secretory and endocytotic pathways join 10 or more compartmentspathways join 10 or more compartments
Direction of the transport and fusion are Direction of the transport and fusion are determined by molecular matching determined by molecular matching (receptor/ligand)(receptor/ligand)
Coated vesiclesCoated vesicles
Role of the coat:Role of the coat: Components of the membrane (e.g. Components of the membrane (e.g.
receptors) are concentrated into patchesreceptors) are concentrated into patches
Removal of coated surfaces and formation Removal of coated surfaces and formation of vesicles of vesicles
Types of coated vesiclesTypes of coated vesicles
Clathrin-Clathrin-coated vesiclescoated vesicles
COPI-COPI-coated vesiclescoated vesicles
COPII-COPII-coated vesiclescoated vesicles
Each type of vesicle has its own transportEach type of vesicle has its own transport
We can distinguish the TEM morphology We can distinguish the TEM morphology of the three types of vesiclesof the three types of vesicles
ClathrinClathrin--coated vesicle:coated vesicle: Golgi – surface mamembrane Golgi – surface mamembrane transporttransport
COPI- COPI- andand COPII- COPII-coatedcoated ve vesicles:sicles:rER - Golgi transportsrER - Golgi transports
The building block of the clathrin-coat:The building block of the clathrin-coat: The triskelionThe triskelion
Clathrin-coat Clathrin-coat Triskelion zikk-zakk and globular structural elementsTriskelion zikk-zakk and globular structural elements
Comparison of clathrin compositionComparison of clathrin composition
Light chain
Heavy chain
Protein-protein and protein-lipid associationsProtein-protein and protein-lipid associations under clathrin coatunder clathrin coat
Clathrin binding proteins in MammalsClathrin binding proteins in Mammals
Alberts et all. Molecular Biology of the Alberts et all. Molecular Biology of the cellcell
Releasing of clathrin-coated vesiclesReleasing of clathrin-coated vesicles
Role of dynamin in the process of Role of dynamin in the process of vesicle releasevesicle release
Dynamin is a G-Dynamin is a G-protein, it binds protein, it binds and cleaves GTPand cleaves GTP
Alberts et all. Molecular Biology of the cellAlberts et all. Molecular Biology of the cell
Receptor-mediated Receptor-mediated endocytosisendocytosis
Alberts et all. Molecular Biology of the cellAlberts et all. Molecular Biology of the cell
Receptor-mediated Receptor-mediated endocytosisendocytosis
SummarySummary: Clathrin-coated vesicule: Clathrin-coated vesicule
SummarySummary: : COPIICOPII-coated vesicle-coated vesicle
SummarySummary: : COPICOPI-coated vesicle-coated vesicle
Fusion of vesicle and target membrane (1)Fusion of vesicle and target membrane (1)
Fusion of vesicle and target membrane (2)Fusion of vesicle and target membrane (2)
NSF – N-ethylmaleimide sensitive factorSNAP – soluble NSF attachment proteinSNAP-25 – synaptosomal associated protein 25 kDaVAMP – vesicle associated membrane protein
A significant component of the vesicle-membraneA significant component of the vesicle-membrane fusion: fusion: a protonpumpa protonpump
a subunit –VPH1
d subunitVMA6
4c, c’ and c’’ subunit –VMA3, VMA11, VMA16
Association of main components in membrane fusionAssociation of main components in membrane fusion
SNAP-25 – synaptosomal associated protein 25 kDaVAMP – vesicle associated membrane protein
SNAP-25SNAP-25 VAMPVAMP SyntaxinSyntaxin
n-Sec1-syntaxinn-Sec1-syntaxinkomplexkomplex
SyntaxinSyntaxin
complexcomplex
n-Sec1n-Sec1
Vesicularis transport –Vesicularis transport –„„Budding”Budding”
Vesicularis transport –Vesicularis transport –„„Docking”Docking”
„„Kiss and run” fusionKiss and run” fusion
syntaxin
VAMP
SNAP-25
egyéb
CCP – cl.-coated pitCCV – cl-coated vesic.DCV – dense core vesic.IC – intermed. comp.
Subcellular distribution of SNARE proteinsSubcellular distribution of SNARE proteins
SNARE – soluble N-ethylmaleimide sensitive factor attachment protein receptor
Role of G-proteins in vesicular trasport (1)Role of G-proteins in vesicular trasport (1)
Rab-cycleRab-cycle
Role of G-proteins in vesicular trasport (2)Role of G-proteins in vesicular trasport (2)
S. cerevisiae C. elegans D. melanogaster H. sapiens0
5000
10000
15000
20000
25000
30000F
elté
tele
zett
gén
ek s
zám
a
Number of genes responsible for vesicular transportNumber of genes responsible for vesicular transportPhylogenetical approachesPhylogenetical approaches
Evolution of SNARE-sEvolution of SNARE-s
S. cerevisiae H. sapiens