Signal peptide peptidase-like 2a and b (SPPL2a/b) are aspartyl intramembrane proteases and cleave tail-anchored proteins as well as N-terminal fragments (NTFs) derived from type II-oriented transmembrane proteins. How these proteases recruit substrates and cleavage is regulated, is still incompletely understood. We found that SPPL2a/b localize to detergent-resistant membrane (DRM) domains with the characteristics of tetraspanin-enriched microdomains (TEMs). Based on this, association with several tetraspanins was evaluated. We demonstrate that not only SPPL2a/b but also their substrates tumor necrosis factor (TNF) and CD74 associate with tetraspanins like CD9, CD81, and CD82 and/or TEMs and analyze the stability of these complexes in different detergents. CD9 and CD81 deficiency has protease- and substrate-selective effects on SPPL2a/b function. Our findings suggest that reciprocal interactions with tetraspanins may assist protease-substrate encounters of SPPL2a/b within the membrane. Beyond SPP/SPPL proteases, this supports previous concepts that tetraspanins facilitate membrane-embedded proteolytic processes.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10509304PMC
http://dx.doi.org/10.1016/j.isci.2023.107819DOI Listing

Publication Analysis

Top Keywords

intramembrane proteases
8
sppl2a/b substrates
8
tetraspanin-enriched microdomains
8
cd9 cd81
8
sppl2a/b
6
dynamic association
4
association intramembrane
4
proteases
4
proteases sppl2a/b
4
substrates tetraspanin-enriched
4

Similar Publications

Isolation and characterization of quinoa antimicrobial peptides and its effect on the microbial diversity of fresh apple juice.

Food Chem

December 2024

Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830017, China. Electronic address:

Article Synopsis
  • The study successfully developed antimicrobial peptides (AMPs) from quinoa using mixed-bacteria fermentation, which showed high antibacterial activity and stability.
  • Among the 9 peptide fractions analyzed, F1 was identified as the most effective in inhibiting bacterial growth in apple juice, particularly against Escherichia coli and Staphylococcus aureus.
  • The specific peptide AGAAPE demonstrated significant stability and resistance under various conditions, and its antimicrobial action was attributed to damaging bacterial membranes, making it a potential solution for preserving fresh juice.
View Article and Find Full Text PDF

4-Oxo-β-lactams as Covalent Inhibitors of the Mitochondrial Intramembrane Protease PARL.

ACS Med Chem Lett

December 2024

Laboratory of Chemical Biology, Department of Cellular and Molecular Medicine, KU Leuven - University of Leuven, Herestraat 49 box 901b, 3000 Leuven, Belgium.

Rhomboid proteases play a variety of physiological roles, but rhomboid protease inhibitors have been mostly developed for the model rhomboid GlpG. In this work, we screened different electrophilic scaffolds against the human mitochondrial rhomboid PARL and found 4-oxo-β-lactams as submicromolar inhibitors. Multifaceted computations suggest explanations for the activity at the molecular scale and provide models of covalently bound complexes.

View Article and Find Full Text PDF
Article Synopsis
  • Alzheimer's disease (AD) is linked to secretases, which are enzymes that cleave proteins, playing a vital role in regulating key factors like amyloid precursor protein (APP) and Notch that influence both AD and cancer.
  • The article details the functions, cleavage sites, and biological roles of six secretase types (α, β, γ, δ, ε, η) and highlights their similarities and differences in how they interact with APP and Notch to affect disease progression.
  • It also discusses the potential of secretase inhibitors as a treatment strategy in AD and cancer, reviewing their chemical structures, current research stages, and future development prospects.
View Article and Find Full Text PDF

Structural insights into regulated intramembrane proteolysis by the positive alginate regulator MucP from Pseudomonas aeruginosa.

Biochem Biophys Res Commun

December 2024

College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Nankai International Advanced Research Institute (Shenzhen Futian), Nankai University, Tianjin 300071, China; Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China. Electronic address:

Regulated intramembrane proteolysis (RIP) is a fundamentally conserved mechanism involving sequential cleavage by a membrane-bound Site-1 protease (S1P) and a transmembrane Site-2 protease (S2P). In the opportunistic pathogen Pseudomonas aeruginosa, the alternate sigma factor σ activates alginate production and in turn is regulated by the MucABCD system. The anti-sigma factor MucA, which inhibits σ, is sequentially cleaved via RIP by AlgW (S1P) and MucP (S2P) respectively.

View Article and Find Full Text PDF

Cleavage of transmembrane segments on target proteins by the aspartyl intramembrane protease signal peptide peptidase (SPP, encoded by HM13) has been linked to immunity, viral infection and protein quality control. How SPP recognizes its various substrates and specifies their fate remains elusive. Here, we identify the lanosterol demethylase CYP51A1 as an SPP substrate and show that SPP-catalysed cleavage triggers CYP51A1 clearance by endoplasmic reticulum-associated degradation (ERAD).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!