Evaluation Summary:
This is a valuable manuscript that addresses an important question and provides interesting mechanistic insights into the roles of specific regions of the IR and IGF1R in their activation. While many of the data convincingly support the conclusions, in some areas the data are incomplete so we are left with an unfinished picture of the mechanisms of activation of the IR and IGF1R, and why they differ.
(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1, Reviewer #2 and Reviewer #3 agreed to share their names with the authors.)