Frizzled4 proximity interactors

ABSTRACT: Frizzled4 (FZD4) is a pivotal receptor for Norrin and Wnt7a/b that mediates CNS angiogenesis, blood-brain barrier function and blood-retina barrier function. FZD4 is a target for pharmacological interventions in retinal and neurological disease. In order to understand mechanisms of regulation of Frizzled4 activity, two proximity biotinylation screens were performed, one in HEK293T cells and one in HeLa cells. For the screen in HEK293T cells, cells were transiently transfected. 24 hours later, cells were stimulated with 50 µM biotin for an additional 24 hours. Samples were processed and subjected to LC-MS/MSas described (PMID: 29516480). Samples S480 and S483 were biological replicates of cells co-transfected with V5-FZD4-BioID, HA-LRP5, and HA-TSPAN12 to reconstitute the norrin receptor complex. Samples S481 and S484 were biological replicates of cells co-transfected with V5-FZD4-BioID, HA-LRP5, and HA-TSPAN12 that were stimulated with flag-AP-Norrin conditioned media during the 24 hour biotin incubation period to induce norrin/frizzled4 signaling. Sample S479 and S482 were biological replicates of cells co-transfected with GFP-BioID, HA-LRP5, and HA-TSPAN12 as negative control. For the screen in HeLa cells, cells were transfected and biotinylated as described above. Sample S454 was transfected with V5-FZD4 (without BioID fusion, as a negative control). Sample S455 was transfected with GFP-BioID as another negative control. Sample S456 and S457 were transfected with V5-FZD4-BioID, of which only S457 was stimulated with flag-AP-Norrin conditioned medium during the biotin incubation period in order to induce FZD4 endocytosis. Multiple known and novel proximity interactors were identified in HEK293T and HeLa cells with high specificity. Comparisons of cells stimulated with norrin vs. vehicle indicate that proximity interactors of FZD4 were largely similar in cells with and without norrin stimulation in an overexpression context.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Harald Junge  

LAB HEAD: Harald Junge

PROVIDER: PXD065058 | Pride | 2026-05-15

REPOSITORIES: Pride