8SE7

HTRA-1 PDSA bound to CKP 1A8

8SE7 の概要

• エントリーDOI: 10.2210/pdb8se7/pdb
• 分子名称: Serine protease HTRA1, Cysteine knot peptide (3 entities in total)
• 機能のキーワード: protease, complex, cysteine knot peptide, peptide binding protein
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 24
• 化学式量合計: 367775.74

構造登録者

Ultsch, M.H.,Kirchhofer, D.,Wei, Y. (登録日: 2023-04-08, 公開日: 2024-07-03, 最終更新日: 2025-01-15)

主引用文献

Li, Y.,Wei, Y.,Ultsch, M.,Li, W.,Tang, W.,Tombling, B.,Gao, X.,Dimitrova, Y.,Gampe, C.,Fuhrmann, J.,Zhang, Y.,Hannoush, R.N.,Kirchhofer, D.
Cystine-knot peptide inhibitors of HTRA1 bind to a cryptic pocket within the active site region.
Nat Commun, 15:4359-4359, 2024

PubMed Abstract: Cystine-knot peptides (CKPs) are naturally occurring peptides that exhibit exceptional chemical and proteolytic stability. We leveraged the CKP carboxypeptidase A1 inhibitor as a scaffold to construct phage-displayed CKP libraries and subsequently screened these collections against HTRA1, a trimeric serine protease implicated in age-related macular degeneration and osteoarthritis. The initial hits were optimized by using affinity maturation strategies to yield highly selective and potent picomolar inhibitors of HTRA1. Crystal structures, coupled with biochemical studies, reveal that the CKPs do not interact in a substrate-like manner but bind to a cryptic pocket at the S1' site region of HTRA1 and abolish catalysis by stabilizing a non-competent active site conformation. The opening and closing of this cryptic pocket is controlled by the gatekeeper residue V221, and its movement is facilitated by the absence of a constraining disulfide bond that is typically present in trypsin fold serine proteases, thereby explaining the remarkable selectivity of the CKPs. Our findings reveal an intriguing mechanism for modulating the activity of HTRA1, and highlight the utility of CKP-based phage display platforms in uncovering potent and selective inhibitors against challenging therapeutic targets.

PubMed: 38777835
DOI: 10.1038/s41467-024-48655-w

実験手法

X-RAY DIFFRACTION (2.96 Å)