PAPP-A and PAPP-A2 are two isoforms of pregnancy-associated plasma protein A that cleave insulin-like growth factor binding proteins (IGFBPs) to modulate insulin-like growth factor signaling, however the structure and function of PAPP-A2 remain underexplored. Here, the authors report the cryo-EM structure of PAPP-A2, computational modeling of the PAPP-A2/IGFBP5 complex, and biochemical studies that reveal unique structural features and a lower IGFBP5 cleaving efficiency compared with PAPP-A.
- Janani Sridar
- Amirhossein Mafi
- Qi Hao
