Seidler Contractile Proteins Flashcards
MyHC IIa gene and muscle fiber type?
MYH2
type 2A
embryonic MyHC gene and muscle fiber type?
MYH3
fetal development, muscle regeneration
Smooth Muscle MyHC gene and muscle fiber type?
MYH11
smooth m.
fetal MyHC gene and muscle fiber type?
MYH8
fetal development, muscle regeneration
Beta-cardiac MyHC gene and muscle fiber type?
MYH7
heart ventricles
alpha-cardiac MyHC gene and muscle fiber type?
MYH6
heart atria
Extraocular MyHC gene and muscle fiber type?
MYH13
extraocular muscle
MyHC 1 gene and muscle fiber type?
MYH7
type 1
mutation in what is associated with myosin storage myopathy?
what kind of myopathy?
MYH7
distal rod
where does myosin self-assemble?
what chains make it up?
what can the head region do?
what is its rotational symmetry?
at the tails
2 heavy, 4 light
hydrolyze ATP
30 degrees
how is actin arranged?
G-actin assembles into F-actin
Each G-actin binds 4 neighbors
what binds free G-actin first?
ATP
what does tropomodulin do?
caps the minus end, preventing further polymerization
what does CapZ (b-actinin) do?
associates w/a-actinin
caps at the plus end
what does Nebulin do?
ruler and template for actin polymerization
what does Troponin T bind to?
function?
tropomyosin
positions the complex on the filament
what does Troponin I bind to?
function?
actin
inhibits myosin binding
what does Troponin C bind to?
function?
binds Ca2+
relieves inhibition
what do costameres do?
tether Z disc to sarcolemma
what is titin?
functions?
sarcomere ruler
passive elasticity
muscle signaling
balances forces across sarcomere
what is diagnostic for a heart attack?
CK-MB
describe the smooth m. contraction with Calcium and calmodulin
Calmodulin binds calcium, this binds the myosin light-chain kinase
kinase will phosphorylate the myosin light chain and myosin proteins get activated
where is dystrophin located?
function?
costameres
tethers myofiber bundles to surface membranes and maintains the integrity of surface membrane during sheer stress of muscle contraction
What is GSD V/McArdle disease?
deficiency in MUSCLE glycogen phosphorylase (RLS of glycogen degradation to release G1P)
what are the Sx of McArdle disease?
m. cramping, myoglobinuria
it is allosterically activated by AMP
What is Her’s disease?
how is it regulated?
GSD VI, mutation in LIVER glycogen phosphorylase
allosterically inhibited by ATP and G6P
inactivated by free glucose, NOT AMP
what is sensitive to calcium?
muscle isozyme of phosphorylase
defect in dystrophin results in what?
DMD, costamere disorganization, sarcolemma fragility, muscle weakness
what is common with in-frame dystrophin mutations?
out-frame?
BMD
DMD
what is found in cardiac muscle after a MI?
what is found in skeletal muscle?
cTn-1
sTn-1
MyHC IIx/d gene and muscle fiber type?
MYH1
type 2b
