Abstract Proteins rarely act in isolation, but rather function in multi-protein complexes. Accordingly, protein-protein interactomes are exceptionally valuable resources that provide deep mechanistic insights and generate myriad hypotheses. Current methods for interactome mapping, such as affinity purification mass-spectrometry (APMS), are extremely difficult to deploy in vivo, so little comprehensive interactome data yet exists for developing embryos and even less for specific tissues within embryos. This fact poses an especially acute problem for understanding highly dynamic processes in which post-transcriptional controls dominate, for example collective cell movements. Here, we will use tissue engaged in convergent extension, a crucial collective movement that elongates the axis of animal embryos, to test the efficacy of new label-free interactome mapping approaches. Successful completion of the project will therefore be significant both for developing broadly applicable new methods and also for providing systems-level insights into a disease- relevant, vertebrate collective cell movement.