Download MendeleyCryo-EM structure of human PAPP-A2 and mechanism of substrate recognition.
Sridar, J., Mafi, A., Judge, R.A., Xu, J., Kong, K.A., Wang, J.C.K., Stoll, V.S., Koukos, G., Simon, R.J., Eaton, D., Bratkowski, M., Hao, Q.(2023) Commun Chem 6: 234-234
- PubMed: 37898658
- DOI: https://doi.org/10.1038/s42004-023-01032-y
- Primary Citation of Related Structures:
8SL1 - PubMed Abstract:
Pregnancy-Associated Plasma Protein A isoforms, PAPP-A and PAPP-A2, are metalloproteases that cleave insulin-like growth factor binding proteins (IGFBPs) to modulate insulin-like growth factor signaling. The structures of homodimeric PAPP-A in complex with IGFBP5 anchor peptide, and inhibitor proteins STC2 and proMBP have been recently reported. Here, we present the single-particle cryo-EM structure of the monomeric, N-terminal LG, MP, and the M1 domains (with the exception of LNR1/2) of human PAPP-A2 to 3.13 Å resolution. Our structure together with functional studies provides insight into a previously reported patient mutation that inactivates PAPP-A2 in a distal region of the protein. Using a combinational approach, we suggest that PAPP-A2 recognizes IGFBP5 in a similar manner as PAPP-A and show that PAPP-A2 cleaves IGFBP5 less efficiently due to differences in the M2 domain. Overall, our studies characterize the cleavage mechanism of IGFBP5 by PAPP-A2 and shed light onto key differences with its paralog PAPP-A.
Organizational Affiliation:
Calico Life Sciences LLC, South San Francisco, CA, 94080, USA.
