Characterization of Heparan Sulfate Proteoglycan-positive Recycling Endosomes Isolated from Glioma Cells.
BACKGROUND
Heparan sulfate proteoglycans (HSPGs)-dependent endocytic events have been involved in glioma progression. Thus, comprehensive understanding of the intracellular trafficking complexes formed in presence of HSPGs would be important for development of glioma treatments.


METHODS
Subcellular fractionation was used to separate vesicles containing HSPGs from the rat C6 glioma cell line. Isolated HSPG-positive vesicles were further characterized with liquid chromatography-mass spectrometry.


RESULTS
The HSPG-positive vesicular fractions, distinct from plasma membrane-derived material, were enriched in endocytic marker, Rab11. Proteomic analysis identified more than two hundred proteins to be associated with vesicular membrane, among them, over eighty were related to endosomal uptake, recycling or vesicular transport.


CONCLUSIONS
Part of HSPGs in glioma cells is internalized through clathrin-dependent endocytosis and undergo recycling. The development of compounds regulating HSPG-mediated trafficking will likely enable design of effective glioma treatment.
Department of Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan kapobch@tmd.ac.jp.
Katarzyna A
KA
Podyma-Inoue
Department of Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
Takuya
T
Moriwaki
Department of Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
Anupama R
AR
Rajapakshe
Department of Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
Kazue
K
Terasawa
Department of Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
Miki
M
Hara-Yokoyama
D000818:Animals; D045744:Cell Line, Tumor; D002966:Clathrin / Q000235:genetics; D004705:Endocytosis / Q000235:genetics; D011992:Endosomes / Q000378:metabolism / Q000473:pathology; D005910:Glioma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D019812:Heparan Sulfate Proteoglycans / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D040901:Proteomics; D051381:Rats; D022161:Transport Vesicles / Q000378:metabolism* / Q000473:pathology; D020691:rab GTP-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D000099193:rab11 GTP-Binding Proteins
D002966:Clathrin; D019812:Heparan Sulfate Proteoglycans; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins
Proteomics; Rab11; heparan sulfate proteoglycan; transport vesicle