Updated project metadata. The RNA-binding protein Trim71/Lin41 is a phylogenetically conserved developmental regulator that functions in mammalian stem cell reprogramming, brain development and cancer. Trim71 recognizes target mRNAs through hairpin motifs and silences them through molecular mechanisms that await identification. Deposited data are mass spectrometry data from immunoprecipitation experiments with endogenously tagged Trim71, Ago2, and Tnrc6a. Experiments are carried out in mouse embryonic stem cells (mESCs) and uncover reciprocal interactions of Trim71, Ago2, and Tnrc6a. Trim71 protein interactions are largely independent of Ago2 levels, but strongly depend on the presence of RNA. A second set of experiments is mass spectrometry data from immunoprecipitation experiments in mESCs overexpressing a tagged peptide derived from Homo sapiens TNRC6B (‘FLAG-HA::T6BWT::Cherry’), that is known to block the Tnrc6-Ago2 interaction. We show that a wild-type version strongly binds Ago1 and Ago2, but not Trim71, while a mutant version binds neither Ago1, 2, nor Trim71.