Two isoforms (Long isoform ~220 KDa, short isoform ~150 KDa) of the human PRRC2B protein (Uniprot accession Q5JSZ5) were recombinantly expressed with an HA-tag in HEK293 cell lines. The goal of the experiment is to identify differential interactors of the short vs long isoforms, in addition to their common interactors. To this aim, 3 sample types were analyzed by IP-MS: HA-tagged long PRRC2B, HA-tagged short PRRC2B, and HA-tagged mCherry (control). Four biological replicates were analyzed from each experimental group.