Question: In no more than 1 paragraph, describe the mechanisms of selective sorting of proteins to axons and dendrites.
Posted: Tue Jul 12, 2022 1:18 pm
Question:
In no more than 1 paragraph, describe the mechanisms ofselective sorting of proteins to axons anddendrites. In your answer: (1) discuss the cytoskeletal elementsand motor proteins that are involved insorting and explain how sorting is achieved, and (2) compare axonsand dendrites with regard to theextent to which they use this sorting mechanism.Key points:(1) (2 points) Vesicles carrying the proteins initially will betransported on microtubules by kinesins (OKto include dyneins here for dendrites, too, but mentioning dyneinis not necessary).(2) (2 points) As a vesicle tries to enter the axon, the vesiclewill encounter actin filaments in the axoninitial segment, organized with their plus ends oriented toward thesoma.(3) (5 points) If the protein is an axonal protein, it should havea Myosin VI, which carries the cargotoward the minus end of actin and into the axon.Then the cargo will hop back onto the microtubules to betransported down the axon by kinesins.(4) (4 points) If the protein is a dendritic protein, it shouldhave a Myosin Va, which can only carry cargotoward the plus end of actin, So, the dendrite proteins will turnaround when they encounter the axoninitial segment and go back into the soma.(5) (3 points) All cargo can enter the dendrites, walking alongmicrotubules, regardless of whether theyare axonal or dendritic proteins.
My answer:
"Polarized sorting of newly-synthesized proteins to thesomatodendritic and axonal domains of neurons occurs by selectiveincorporation into distinct populations of vesicular transportcarriers These vesicles subsequently move to their correspondingneuronal domains along cytoskeletal tracks. The boundary betweenthe somatodendritic and axonal domains has been located at the axoninitial segment, a specialized region of the proximal axoncomprising a high concentration of surface voltage-gated ionchannels and cell-adhesion molecules that are anchored by asubmembranous assembly of ankyrin G. The AIS was also proposed tocontain a cytoplasmic filter that allow passage of axonal but notdendritic vesicle towards the distal axon."
Please let me know what of all 5 "key points" mentioned abovethat I missed and how I might improve upon them
In no more than 1 paragraph, describe the mechanisms ofselective sorting of proteins to axons anddendrites. In your answer: (1) discuss the cytoskeletal elementsand motor proteins that are involved insorting and explain how sorting is achieved, and (2) compare axonsand dendrites with regard to theextent to which they use this sorting mechanism.Key points:(1) (2 points) Vesicles carrying the proteins initially will betransported on microtubules by kinesins (OKto include dyneins here for dendrites, too, but mentioning dyneinis not necessary).(2) (2 points) As a vesicle tries to enter the axon, the vesiclewill encounter actin filaments in the axoninitial segment, organized with their plus ends oriented toward thesoma.(3) (5 points) If the protein is an axonal protein, it should havea Myosin VI, which carries the cargotoward the minus end of actin and into the axon.Then the cargo will hop back onto the microtubules to betransported down the axon by kinesins.(4) (4 points) If the protein is a dendritic protein, it shouldhave a Myosin Va, which can only carry cargotoward the plus end of actin, So, the dendrite proteins will turnaround when they encounter the axoninitial segment and go back into the soma.(5) (3 points) All cargo can enter the dendrites, walking alongmicrotubules, regardless of whether theyare axonal or dendritic proteins.
My answer:
"Polarized sorting of newly-synthesized proteins to thesomatodendritic and axonal domains of neurons occurs by selectiveincorporation into distinct populations of vesicular transportcarriers These vesicles subsequently move to their correspondingneuronal domains along cytoskeletal tracks. The boundary betweenthe somatodendritic and axonal domains has been located at the axoninitial segment, a specialized region of the proximal axoncomprising a high concentration of surface voltage-gated ionchannels and cell-adhesion molecules that are anchored by asubmembranous assembly of ankyrin G. The AIS was also proposed tocontain a cytoplasmic filter that allow passage of axonal but notdendritic vesicle towards the distal axon."
Please let me know what of all 5 "key points" mentioned abovethat I missed and how I might improve upon them