Expression of the novel Golgi protein GoPro49 is developmentally regulated during mesenchymal differentiation

The Golgi complex is the major cell organelle responsible for protein glycosylation and secretion. In this article, we show that GoPro49 is a new gene expressed specifically in mesenchymal and cartilaginous tissues during development. The corresponding human homologue was identified in our previous Golgi proteomics study and was shown to localize to the Golgi complex as an EGFP-fusion protein. Furthermore, we show using in situ hybridization that GoPro49 expression pattern is both restricted and developmentally regulated. It is specific in vertebrae, ribs, and limbs, and in the craniofacial area in nasal septum and dental follicle. In the trunk, GoPro49 expression decreases before final chondrocyte differentiation, while in the craniofacial area expression is still observed in postnatal tissues. This is the first time a Golgi membrane protein is shown to be expressed in a developmentally regulated manner during mesenchymal and cartilage development in mammals.