MAG2 (also known as brain cyst load-associated antigen, BCLA) localizes within the cyst matrix (Dard et al., 2021), interacts with ICN, and may coordinate with previously reported PVM-localized GRAs and IVN-associated GRAs to regulate the maturation of the cyst matrix and cyst wall (Guevara et al., 2019, 2020b; Tu et al., 2020a; Figure 2). Here, RETREG2 is linked to cyst.