Updated project metadata. Mass spectrometry analysis was carried out to investigate the protein expression landscape of RNA-binding proteins (RBPs) during a time-course of spontaneously differentiating human embryonic stem cells (hESCs). Mass spectrometry was performed on whole-cell extracts of differentiating TE03 (I3) hESCs at four time-points (days 0, 23, 39, and 54), each with two biological replicates.