Lecture 15 Flashcards
the matrix controls the mechanical propertieis of tissues - this is determined by ____
the specific protein composition of the ECM
what percentage of the protein mass in our body is made up of collagens?
25%
_____ content correlates with tissue stiffness
collagen I
SUN and KASH proteins link filaments in the _____ to nuclear lamins ______
cytoplasm
inside the nucleus
cells alter gene expression in response to changes in the ____ of their environment in a mechanism involving ___ and __ complexes
stiffness
SUN
KASH
____ is a key component of bone
collagen I
osteoblasts do what?
deposit the ECM in bone
___ and ____ are the main components of the basal lamina
laminin
collagen IV
collagen is made by connective tissue cells: (2)
osteoblasts (bone)
fibroblasts (skin, tendon)
collagen is a single ____ that is translated at _____ and passed through the ER membrane into the ____ where it forms a triple stranded _______
polypeptide chain
endoplasmic reticulum
lumen
helical procollagen molecule
collagen is secreted as a _____ called ____
precursor
procollagen
collagen fibres must be ___
properly aligned
ECM diseases include (3)
- abnormally stretchable skin
- brittle bone disease
- skeletal abnormalities (short bones, abnormal bone structure) - achondroplasia
integrins
trans-membrane proteins in the plasma membrane
link ECM to cell’s cytoskeleton
type of cytoskeleton linkage depends on context
GAGs
glycosaminoglycans
- large, neg charged polysaccharides
- strongly hydrophilic
- occupy huge volume relative to mass
