TY - JOUR
T1 - Possible role of LRP1, a CCN2 receptor, in chondrocytes
AU - Kawata, Kazumi
AU - Eguchi, Takanori
AU - Kubota, Satoshi
AU - Kawaki, Harumi
AU - Oka, Morihiko
AU - Minagi, Shogo
AU - Takigawa, Masaharu
N1 - Funding Information:
This work was supported by Grants-in-Aid for Scientific Research (S) (to M.T.) and (C) (to S.K.) and Exploratory Research (to M.T.) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan, Grants-in-Aid for Fellows of the Japanese Society for the Promotion of Science (to T.E.), and grants from the Sumitomo Foundation (to M.T.), Kurozumi Medical Foundation (to S.K.) and the Nakatomi Foundation (to S.K.).
PY - 2006/6/30
Y1 - 2006/6/30
N2 - Low density lipoprotein receptor (LDLR)-related protein 1 (LRP1/CD91) is one of the receptors of CCN2 that conducts endochondral ossification and cartilage repair. LRP1 is a well-known endocytic receptor, but its distribution among chondrocytes remains to be elucidated. We herein demonstrate for the first time that the distribution of LRP1 in chondrocytes except for hypertrophic chondrocytes in vivo and in vitro. Interestingly, the LRP1 levels were higher in mature chondrocytic HCS-2/8 and osteoblastic SaOS-2 than in other cells, whereas the other LDLR family members involved in ossification were detected at lower levels in HCS-2/8. It was interesting to note that in HCS-2/8, LRP1 was observed not only on the cell surface and in the cytoplasm, but also in the nucleus. Exogenously added CCN2 was incorporated into HCS-2/8, which was partially co-localized with LRP1, and targeted to the recycling endosomes and nucleus as well as the lysosomes. These findings suggest specific roles of LRP1 in cartilage biology.
AB - Low density lipoprotein receptor (LDLR)-related protein 1 (LRP1/CD91) is one of the receptors of CCN2 that conducts endochondral ossification and cartilage repair. LRP1 is a well-known endocytic receptor, but its distribution among chondrocytes remains to be elucidated. We herein demonstrate for the first time that the distribution of LRP1 in chondrocytes except for hypertrophic chondrocytes in vivo and in vitro. Interestingly, the LRP1 levels were higher in mature chondrocytic HCS-2/8 and osteoblastic SaOS-2 than in other cells, whereas the other LDLR family members involved in ossification were detected at lower levels in HCS-2/8. It was interesting to note that in HCS-2/8, LRP1 was observed not only on the cell surface and in the cytoplasm, but also in the nucleus. Exogenously added CCN2 was incorporated into HCS-2/8, which was partially co-localized with LRP1, and targeted to the recycling endosomes and nucleus as well as the lysosomes. These findings suggest specific roles of LRP1 in cartilage biology.
KW - CCN2/connective tissue growth factor (CTGF)
KW - Cartilage
KW - Chondrocyte differentiation
KW - Endocytosis
KW - Low density lipoprotein receptor-related protein 1 (LRP1)
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U2 - 10.1016/j.bbrc.2006.04.109
DO - 10.1016/j.bbrc.2006.04.109
M3 - Article
C2 - 16690029
AN - SCOPUS:33646853310
VL - 345
SP - 552
EP - 559
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 2
ER -