Intracellular Vesicular Traffic 2 Flashcards
Lysosomes are heterogeneous - derived from _____ endosomes.
Late
Lysosomes are membrane enclosed compartments filled with _____ ______.
Hydrolytic enzymes
Lysosomes are important for _____ _____ of macromolecules
intracellular digestion
There are about 40 types of enzymes in lysosomes: name 7 acid hydrolases
Proteases, nucleases, glycosidses, lipases, phopsholipases, phosphatases, and sulfatases
Lysosome enzymes require ____ ______ and ____ _____ for optimal activation
acid environment
proteolytic cleavage
Lysosomal ________ protects cell against is enzymes.
membrane
________ in membrane pump out end products of digestion.
Transporters
_____ ______ pumps H+ into lysosomes to maintain the acidic pH and to drive transport of small metabolites.
Vacuolar ATPase
pH in lysosomes is about:
5.0
Transport from TGN to lysosomes uses the pathway that delivers _____ ______ and ______ to lysosomes.
Membrane proteins
hydrolases
Membrane proteins and hydrolases are co-translationally transported into ____ _____ and then transported via Golgi complex to _____.
Rough ER
TGN
TGN buds of into _______.
Endosomes
Endosomes develop into _______.
Lysosomes
Lysosomal hydrolases have _____-__-_____ attached to them in the ____.
mannose-6-phosphate (M6P)
CGN
____ ______ in TGN recognize the sugar.
M6P receptors
M6P receptors bind to hydrolases and adaptor proteins in assembling _____ coats. All packaged into ______-coated vesicles that bud from ____.
Clathrin, clathrin, TGN
Contents from TGN are delivered into ______ and then to _______.
Endosomes
Lysosomes
What enzyme transfers a phosphate to lysosomal hydrolase with terminal mannose residue?
GlcNAc phosphotransferase
end product is M6P
Lysosomal storage diseases arise from ___ ____ in lysosomal _______.
Genetic defects, hydrolases
In lysosomal storage disease, there is an accumulation of _____ _____ in lysomsomes.
undigested material
______ _____: mutation in the enzyme required to break down glycosaminoglycan chains.
Hurler’s disease
______ ____ ____: all of the lysosomal hydrolases are missing in fibroblasts.
Inclusion cell disease
Defective or missing _____ ________, an enzyme that adds _____ to lysosomal hydrolases, the enzymes are not _________ and hence not sorted into vesicles and not delivered into lysosomes.
They are instead secreted into _____.
GlcNAc phosphotransferase,
M6P
phosphorylated
Blood
Endocytosis: uptake of ______ from ______ across plasma membrane.
macromolecules
exterior