Key structural protein of the Golgi apparatus (PubMed:33301566). The membrane cisternae of the Golgi apparatus adhere to each other to form stacks, which are aligned side by side to form the Golgi ribbon (PubMed:33301566). Acting in concert with GORASP1/GRASP65, is required for the formation and maintenance of the Golgi ribbon, and may be dispensable for the formation of stacks (PubMed:33301566). However, other studies suggest that GORASP2 plays a role in the assembly and membrane stacking of the Golgi cisternae, and in the process by which Golgi stacks reform after breakdown during mitosis and meiosis (PubMed:10487747, PubMed:21515684, PubMed:22523075). May regulate the intracellular transport and presentation of a defined set of transmembrane proteins, such as transmembrane TGFA (PubMed:11101516). Required for normal acrosome formation during spermiogenesis and normal male fertility, probably by promoting colocalization of JAM2 and JAM3 at contact sites between germ cells and Sertoli cells (By similarity). Mediates ER stress-induced unconventional (ER/Golgi-independent) trafficking of core-glycosylated CFTR to cell membrane (PubMed:21884936, PubMed:27062250, PubMed:28067262). {ECO:0000250|UniProtKB:Q99JX3, ECO:0000269|PubMed:10487747, ECO:0000269|PubMed:11101516, ECO:0000269|PubMed:21515684, ECO:0000269|PubMed:21884936, ECO:0000269|PubMed:22523075, ECO:0000269|PubMed:27062250, ECO:0000269|PubMed:28067262}. This is the function of GORASP2 (golgi reassembly stacking protein 2, Ensembl gene identifier ENSG00000115806).