Immunohistochemical characterization of NOV expression in 6 month males (A–K) and females (L–O). NOV is expressed in the most superficial layer of the articular cartilage at margins of the joint and meniscus (A, B, arrowhead), the synovial intima (A, B) and a subset of cells in the calcified layer (A, D, arrow) and meniscus (B). NOV is also present in the synovial lining of the femur and lining the collateral ligaments (E), and in the attachment site of the fibrous capsule (fc) to the patella (F, G). No signal was detected in Novdel3−/− fibrous capsule (H, I), meniscus (J) or articular cartilage (K). In females NOV is also expressed in the superficial layer (L, arrowhead), the synovial intima (N), a subset of cells in the calcified layer and meniscus (L, M) and the patella (O). Scale bars are 100 μm unless indicated. tib; tibia, m; meniscus, s; synovium, fem; femur, ac; articular cartilage, tl; tideline, cc; calcified cartilage, l; collateral ligament, pat; patella.