Expressed in the interterritorial matrix of articular deep zone cartilage (at protein level). Isoform 1 and isoform 2 are expressed in brain. Isoform 1 is detected in lung and chondrocytes. Detected in cartilage, bone, cultured chondrocytes and lung, and at low levels in heart. Not detected in osteoblasts. Up-regulated by BMP4 (at protein level). Up-regulated in mesenchymal stem cells undergoing chondrogenic differentiation and by BMP4. O-glycosylated. Shares an exon with the neighboring tail-to-tail oriented gene GOLGA7B. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus.