Fig 2. Expression pattern of the transgenes by immunohistochemistry.

Transgene expression examined by immunohistochemistry using 1-month-old tibia tissue sections. A, No background signal was detected by anti-GFP antibody in wild-type mice. B, Intense signal from the anti-GFP antibody was detected in both the osteoblasts and osteocyte-like cells (red arrow heads) located in the bone matrix. C-D, Immunofluorescence staining to examine co-localization of LRAP and EGFP in tibia sections. Very faint signals were detected from WT tissue by the anti-amelogenin antibody (C, red arrow). EGFP (green) and LRAP (red) were co-expressed in most of the osteoblast like cells in TgLRAP (D, yellow cells indicated by white arrows). Cells that appeared to be osteocytes showed only the EGFP signal, suggesting the LRAP might be quickly degraded compared to EGFP in some cells (white arrow heads). On the other hand, endogenous amelogenin was detected in osteocyte-like cells located in the bone matrix without EGFP signal (red arrow). Red; anti-amelogenin antibody, Green; anti-GFP antibody, Yellow; merged. Dashed lines: border between bone matrix and bone marrow, Black bars = 200 μm, White bars = 50 μm. WT; wild-type mouse, TgLRAP; LRAP transgenic mouse.