This is a glycine-rich domain that is the most highly conserved region of a family of proteins that in vertebrates are associated with tumours in multiple myelomas. The region may contain nuclear localisation signals, so it might act as a signal molecule in the nucleus [1] [2].

1: Cloning and sequence analysis of tumor-associated gene hMMTAG2 from human multiple myeloma cell line ARH-77. Tian JY, Hu WX, Tian EM, Shi YW, Shen QX, Tang LJ, Jiang YS; Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai). 2003;35:143-148. PMID:12545221

2: Characterization and prediction of protein nucleolar localization sequences. Scott MS, Boisvert FM, McDowall MD, Lamond AI, Barton GJ; Nucleic Acids Res. 2010;38:7388-7399. PMID:20663773