[HTML][HTML] Molecular cloning of a possible cysteine proteinase predominantly expressed in osteoclasts.

K Tezuka, Y Tezuka, A Maejima, T Sato… - Journal of Biological …, 1994 - Elsevier
K Tezuka, Y Tezuka, A Maejima, T Sato, K Nemoto, H Kamioka, Y Hakeda, M Kumegawa
Journal of Biological Chemistry, 1994Elsevier
Osteoclasts are multinucleate giant cells playing key roles in bone resorption. These cells
solubilize mineralized bone matrix by means of acid and protease action; however, the
precise mechanism of this process is not well known. Recently, we succeeded in the
isolation of pure osteoclasts from rabbit bones and constructed a cDNA library. Using a
differential screening procedure, two genes expressed predominantly in osteoclasts
compared with spleen cells were isolated (Tezuka, K., Sato, T., Kamioka, H., Nijweide, PJ …
Osteoclasts are multinucleate giant cells playing key roles in bone resorption. These cells solubilize mineralized bone matrix by means of acid and protease action; however, the precise mechanism of this process is not well known. Recently, we succeeded in the isolation of pure osteoclasts from rabbit bones and constructed a cDNA library. Using a differential screening procedure, two genes expressed predominantly in osteoclasts compared with spleen cells were isolated (Tezuka, K., Sato, T., Kamioka, H., Nijweide, P. J., Tanaka, K., Matsuo, T., Ohta, M., Kurihara, N., Hakeda, Y., and Kumegawa, M. (1992) Biochem. Biophys. Res. Commun. 186, 911-917). One of them, OC-2, was found to encode a possible cysteine proteinase structurally related to cathepsins L and S. By in situ hybridization, OC-2 was confirmed to be expressed in osteoclasts in vivo. By Northern blot analysis, OC-2 was highly and preferentially expressed in osteoclasts compared with other tissues such as kidney, liver, spleen, and lung. The predominant expression of OC-2 in osteoclasts may suggest that OC-2 encodes a protein, possibly a cysteine proteinase, that plays an important role in osteoclastic bone resorption.
Elsevier