In a faf mutant background, vas protein levels are reduced to 51% and 12% of wild-type levels in ovaries and embryos, respectively; polyubiquitinated vas is detected.
Embryonic extracts were cross-linked before the first vas immunoprecipitation. Complexes were isolated by "continuous-elution electrophoresis", then vas was immunoprecipitated again. Purified complexes were subjected to mass spectrometry for protein identification.
