Abstract
Following endocytosis, internalized molecules are found within intracellular vesicles and tubules that move along the cytoskeleton and undergo fission, as demonstrated here using primary cultured rat hepatocytes. Although the use of depolymerizing drugs has shown that the cytoskeleton is not required to segregate endocytic protein, many studies suggest that the cytoskeleton is involved in the segregation of protein in normal cells. To investigate whether cytoskeletal-based movement results in the segregation of protein, we tracked the contents of vesicles during in vitro microscopy assays. These studies showed that the addition of ATP causes fission of endocytic contents along microtubules, resulting in the segregation of proteins that are targeted for different cellular compartments. The plasma membrane proteins, sodium (Na+) taurocholate cotransporting polypeptide (ntcp) and transferrin receptor, segregated from asialoorosomucoid (ASOR), an endocytic ligand that is targeted for degradation. Epidermal growth factor receptor, which is degraded, and the asialoglycoprotein receptor, which remains partially bound to ASOR, segregated less efficiently from ASOR. Vesicles containing ntcp and transferrin receptor had reduced fission in the absence of ASOR, suggesting that fission is regulated to allow proteins to segregate. A single round of fission resulted in 6.5-fold purification of ntcp from ASOR, and 25% of the resulting vesicles were completely depleted of the endocytic ligand.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 833-847 |
| Number of pages | 15 |
| Journal | Traffic |
| Volume | 9 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 2008 |
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Keywords
- Asialoglycoprotein receptor
- Endosome
- Fission
- Microtubules
- Sorting
- Transferrin receptor
ASJC Scopus subject areas
- Biochemistry
- Cell Biology
- Structural Biology
- Molecular Biology
- Genetics
Cite this
Single vesicle analysis of endocytic fission on microtubules in vitro. / Murray, John W.; Sarkar, Souvik; Wolkoff, Allan W.
In: Traffic, Vol. 9, No. 5, 05.2008, p. 833-847.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Single vesicle analysis of endocytic fission on microtubules in vitro
AU - Murray, John W.
AU - Sarkar, Souvik
AU - Wolkoff, Allan W.
PY - 2008/5
Y1 - 2008/5
N2 - Following endocytosis, internalized molecules are found within intracellular vesicles and tubules that move along the cytoskeleton and undergo fission, as demonstrated here using primary cultured rat hepatocytes. Although the use of depolymerizing drugs has shown that the cytoskeleton is not required to segregate endocytic protein, many studies suggest that the cytoskeleton is involved in the segregation of protein in normal cells. To investigate whether cytoskeletal-based movement results in the segregation of protein, we tracked the contents of vesicles during in vitro microscopy assays. These studies showed that the addition of ATP causes fission of endocytic contents along microtubules, resulting in the segregation of proteins that are targeted for different cellular compartments. The plasma membrane proteins, sodium (Na+) taurocholate cotransporting polypeptide (ntcp) and transferrin receptor, segregated from asialoorosomucoid (ASOR), an endocytic ligand that is targeted for degradation. Epidermal growth factor receptor, which is degraded, and the asialoglycoprotein receptor, which remains partially bound to ASOR, segregated less efficiently from ASOR. Vesicles containing ntcp and transferrin receptor had reduced fission in the absence of ASOR, suggesting that fission is regulated to allow proteins to segregate. A single round of fission resulted in 6.5-fold purification of ntcp from ASOR, and 25% of the resulting vesicles were completely depleted of the endocytic ligand.
AB - Following endocytosis, internalized molecules are found within intracellular vesicles and tubules that move along the cytoskeleton and undergo fission, as demonstrated here using primary cultured rat hepatocytes. Although the use of depolymerizing drugs has shown that the cytoskeleton is not required to segregate endocytic protein, many studies suggest that the cytoskeleton is involved in the segregation of protein in normal cells. To investigate whether cytoskeletal-based movement results in the segregation of protein, we tracked the contents of vesicles during in vitro microscopy assays. These studies showed that the addition of ATP causes fission of endocytic contents along microtubules, resulting in the segregation of proteins that are targeted for different cellular compartments. The plasma membrane proteins, sodium (Na+) taurocholate cotransporting polypeptide (ntcp) and transferrin receptor, segregated from asialoorosomucoid (ASOR), an endocytic ligand that is targeted for degradation. Epidermal growth factor receptor, which is degraded, and the asialoglycoprotein receptor, which remains partially bound to ASOR, segregated less efficiently from ASOR. Vesicles containing ntcp and transferrin receptor had reduced fission in the absence of ASOR, suggesting that fission is regulated to allow proteins to segregate. A single round of fission resulted in 6.5-fold purification of ntcp from ASOR, and 25% of the resulting vesicles were completely depleted of the endocytic ligand.
KW - Asialoglycoprotein receptor
KW - Endosome
KW - Fission
KW - Microtubules
KW - Sorting
KW - Transferrin receptor
UR - http://www.scopus.com/inward/record.url?scp=41849085244&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=41849085244&partnerID=8YFLogxK
U2 - 10.1111/j.1600-0854.2008.00725.x
DO - 10.1111/j.1600-0854.2008.00725.x
M3 - Article
VL - 9
SP - 833
EP - 847
JO - Traffic
JF - Traffic
SN - 1398-9219
IS - 5
ER -