13.11.19
L5 – Cell adhesion and migration
Keywords:
Traction (pulling forward), axoneme, protozoa (single celled eukaryotes)
Lecture:
Connective tissues (bonded by matrix) vs epithelial (sheets of cells)
Functions that require cell migration
o Cancer metastasis, angiogenesis, wound repair, pregnancy and immunity
Main way of organizing cells in vert tissue
Non-adherent cells use swimming (flagella)
o Faster than adhesion unless in ECM
o Flagella in sperm and protozoa
Axoneme = causes flagella to move bc is bending core
Containing 9 doublet microtubules in a ring around 2 single
microtubules
Dynein binds doublet microtubules and covers circumference
Dynein provides flexibility for movement of flagella
Kartagener’s syndrome = Dynein defect → immobile sperm →
sterility and high chance of chest infections (immotile cilia)
Basal bodies root cilia and flagella into memb
9 fused triplet microtubules in a cartwheel shape
Cilia beat in whip like fashion and in a wave like pattern with other cilia
o Flagella in bacteria
Repeated flagellin subunits make the flagella
Rotate via rotary motor protein in cell wall
Frequently migrating cells
o Immunity cells (macrophages and neutrophils)
o Osteoclasts
o Fibroblasts (connective tissue)
o Cancer
6 steps of migration (driven by EGF)
o 1) Sense (chemokines = directional)
o 2) Extension/protrusion ll (leading edge of PM forward)
Polymerizing + end actin monomers in the cytoskeleton
Branched structure created by Arp2/3 complex at 70֯ angle
o Lower pressure = ↓∆ puncturing
o Capping filaments stop polymerization by stopping adding
actin monomers
Actin = 5-9nm microfilaments
o Mech stiffness and support
o + face direction of movement and – bind to other filaments
in ARP complexes = 2D
o Involved in cell junctions
Adhere junctions anchor actin to connect cells
o ATP bound
o 3 types of protruding actin structures:
L5 – Cell adhesion and migration
Keywords:
Traction (pulling forward), axoneme, protozoa (single celled eukaryotes)
Lecture:
Connective tissues (bonded by matrix) vs epithelial (sheets of cells)
Functions that require cell migration
o Cancer metastasis, angiogenesis, wound repair, pregnancy and immunity
Main way of organizing cells in vert tissue
Non-adherent cells use swimming (flagella)
o Faster than adhesion unless in ECM
o Flagella in sperm and protozoa
Axoneme = causes flagella to move bc is bending core
Containing 9 doublet microtubules in a ring around 2 single
microtubules
Dynein binds doublet microtubules and covers circumference
Dynein provides flexibility for movement of flagella
Kartagener’s syndrome = Dynein defect → immobile sperm →
sterility and high chance of chest infections (immotile cilia)
Basal bodies root cilia and flagella into memb
9 fused triplet microtubules in a cartwheel shape
Cilia beat in whip like fashion and in a wave like pattern with other cilia
o Flagella in bacteria
Repeated flagellin subunits make the flagella
Rotate via rotary motor protein in cell wall
Frequently migrating cells
o Immunity cells (macrophages and neutrophils)
o Osteoclasts
o Fibroblasts (connective tissue)
o Cancer
6 steps of migration (driven by EGF)
o 1) Sense (chemokines = directional)
o 2) Extension/protrusion ll (leading edge of PM forward)
Polymerizing + end actin monomers in the cytoskeleton
Branched structure created by Arp2/3 complex at 70֯ angle
o Lower pressure = ↓∆ puncturing
o Capping filaments stop polymerization by stopping adding
actin monomers
Actin = 5-9nm microfilaments
o Mech stiffness and support
o + face direction of movement and – bind to other filaments
in ARP complexes = 2D
o Involved in cell junctions
Adhere junctions anchor actin to connect cells
o ATP bound
o 3 types of protruding actin structures:
