Institute for Stroke and Dementia Research (ISD), University Hospital, Ludwig Maximilian University of Munich, Munich, Germany.
Center of Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Essen, Germany.
Nat Commun. 2024 Jul 16;15(1):5944. doi: 10.1038/s41467-024-49982-8.
Loss-of-function mutations in the homotrimeric serine protease HTRA1 cause cerebral vasculopathy. Here, we establish independent approaches to achieve the functional correction of trimer assembly defects. Focusing on the prototypical R274Q mutation, we identify an HTRA1 variant that promotes trimer formation thus restoring enzymatic activity in vitro. Genetic experiments in Htra1 mice further demonstrate that expression of this protein-based corrector in trans is sufficient to stabilize HtrA1-R274Q and restore the proteomic signature of the brain vasculature. An alternative approach employs supramolecular chemical ligands that shift the monomer-trimer equilibrium towards proteolytically active trimers. Moreover, we identify a peptidic ligand that activates HTRA1 monomers. Our findings open perspectives for tailored protein repair strategies.
功能丧失突变导致同源三聚体丝氨酸蛋白酶 HTRA1 脑血管病变。在这里，我们建立了独立的方法来实现三聚体组装缺陷的功能矫正。针对典型的 R274Q 突变，我们鉴定出一种 HTRA1 变体，它能促进三聚体形成，从而在体外恢复酶活性。Htra1 小鼠中的遗传实验进一步表明，这种基于蛋白质的校正物的转染表达足以稳定 HtrA1-R274Q 并恢复脑血管的蛋白质组学特征。另一种方法利用超分子化学配体将单体-三聚体平衡向具有蛋白水解活性的三聚体转移。此外，我们还鉴定出一种能激活 HTRA1 单体的肽配体。我们的研究结果为定制蛋白质修复策略开辟了新的前景。
