New research has advanced our knowledge of multiple roles for PTPRK, a receptor tyrosine phosphatase linked to the regulation of cell-cell adhesion, growth factor signalling and tumor suppression. Through a characterization of the function of PTPRK in human cell lines and mice, the team distinguished catalytic and non-catalytic functions of PTPRK. The findings extend what is known about the signalling mechanisms involving PTPRK as a phosphatase and its role in colorectal health but also shed new light on the extent of its function via non-catalytic signalling mechanisms.