Involved in the maintenance of the Golgi structure. May play a role in hematopoiesis. Interacts with YIPF4 and YIPF5. Localization to the cytoplasm or to the cell membrane is developmentally and ontogenetically regulated. Expressed by nucleated hematopoietic cells (at protein level). Expressed in fetal liver (at protein level). Expressed in embryonic hematopoiesis sites. N-glycosylated in the ER (40 kDa form I), then O-glycosylated in the Golgi apparatus (46 kDa form II), the C-terminal lumenal region is later removed in the Golgi apparatus to produce a 36 kDa form III. O-glycosylated with core 1-like and core 2-like glycans. O-glycan heterogeneity at Thr-346: HexNAc (minor), HexHexNAc (major), Hex1HexNAc2 (minor), Hex2HexNAc2 (minor) and dHex1Hex2HexNAc2 (minor). Belongs to the YIP1 family.