Proteínas gla do osso e cartilagem: importância dos anfíbios e peixes como modelos biológicos para elucidação da sua função e evolução - gla proteins in bone and cartilage: the importance of fish and amphibian models to understand their function and evolution

Gla proteins, as the name indicates, undergo a post-translation modification where specific glutamic acid residues are γ-carboxylated through the action of the ubiquitous enzyme γ-carboxylase and using vitamin K as cofactor. Therefore, these proteins are also called vitamin K dependent proteins or VKD [1, 2]. We can assign VKDs to essentially four different groups: 1) those involved in blood coagulation (such as prothrombin and various coagulation factors; the first group to be discovered), 2) those involved in tissue mineralization (bone and matrix Gla proteins), 3) a nerve growth factor (gas6), and 4) those of unknown function (the latest group to be discovered). The carboxylase enzyme is present in fly and worm but not in yeast, indicating that γ-carboxylation is likely a feature appearing in multicellular eukaryotes