Yonca Erdal, Kubilay Dogan Kılıc, Hatice K Basaloglu and Mehmet Turgut
O type-glycosylation which binding of monosaccharides to Ser and Thr residues on receptor proteins is one of the most common posttranslational modifications. It regulates a variety of biological processes that including cell growth, signaling, protein stability and traffic analysis and cell adhesion [1]. O-type glycosylation is present in humans with at least 20 members, from GALNTl to 14 and from GALNTI to L6. It is catalyzed by GalNAc transferases which a large polypeptide in the Golgi complex [2]. In addition to their role in normal cellular processes, changes in O-glycan compositions alter GALNT expression and cause cancer.