To identify erythroid-specific TENT5C interactors, we employed a modified TurboID proximity biotinylation assay followed by MS/MS analysis of fetal liver erythroblasts differentiated ex vivo. We took advantage of Tent5c-EGFP knock-in mouse line and employed lentiviral vector expressing nanobody anti-EGFP fused with TurboID biotinylase. By introducing this construct to either WT or Tent5c-EGFP erythroblasts, we were able to quantitatively determine the specificity of enriched proteins found in proximity to TENT5C-EGFP compared to the background found in the WT. This approach does not require the introduction of exogenous biotinylase-tagged TENT5C, which expression would be out of place in the earliest stages of erythropoiesis. Importantly, it was designed for the knock-in model in which the expression timing for TENT5C is in accord with the developmental timeline of erythroblasts. Hence, we expected the enriched proximal proteins to be physiologically relevant interactors of TENT5C.