Aberrant Phase Separation is a Common Killing Strategy of Positively Charged Peptides in Biology and Human Disease

Boeynaems, Steven; Ma, Rosa; Yeong,; Ginell, Garrett M.; Chen, Jianhua; Blum, Jacob A.; Nakayama, Lisa; Sanyal, Anushka; Briner, Adam; Haver, Delphi Van; Pauwels, Jarne; Ekman, Axel; Schmidt, Hermann Broder; Sundararajan, Kousik; Porta, Lucas de Carvalho; Lasker, Keren; Larabell, Carolyn A.; Hayashi, Mirian A. F.; Kundaje, Anshul; Impens, Francis; Obermeyer, Allie C.; Holehouse, Alex S.; Gitler, Aaron D.

doi:10.2139/ssrn.4390008

Cited by 6 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is in line with recent reports of the cellular toxicity of cationic peptides and proteins. 45,46 Interestingly, the peptide sequences studied here also bear a close resemblance with antimicrobial peptides, which are typically cationic and 10−25 amino acidlong. Such peptides have been shown to inhibit transcription and translation in vitro and form condensate-like clusters with nucleic acids in bacteria.…”

Section: ■ Conclusionmentioning

confidence: 99%

Charge-Patterned Disordered Peptides Tune Intracellular Phase Separation in Bacteria

Liao,

Yeong,

Obermeyer

2024

ACS Synth. Biol.

View full text Add to dashboard Cite

Subcellular phase-separated compartments, known as biomolecular condensates, play an important role in the spatiotemporal organization of cells. To understand the sequence-determinants of phase separation in bacteria, we engineered protein-based condensates in Escherichia coli using electrostatic interactions as the main driving force. Minimal cationic disordered peptides were used to supercharge negative, neutral, and positive globular model proteins, enabling their phase separation with anionic biomacromolecules in the cell. The phase behavior was governed by the interaction strength between the cationic proteins and anionic biopolymers, in addition to the protein concentration. The interaction strength primarily depended on the overall net charge of the protein, but the distribution of charge between the globular and disordered domains also had an impact. Notably, the protein charge distribution between domains could tune mesoscale attributes such as the size, number, and subcellular localization of condensates within E. coli cells. The length and charge density of the disordered peptides had significant effects on protein expression levels, ultimately influencing the formation of condensates. Taken together, charge-patterned disordered peptides provide a platform for understanding the molecular grammar underlying phase separation in bacteria.

show abstract

Section: ■ Conclusionmentioning

confidence: 99%

Charge-Patterned Disordered Peptides Tune Intracellular Phase Separation in Bacteria

Liao,

Yeong,

Obermeyer

2024

ACS Synth. Biol.

View full text Add to dashboard Cite

show abstract

C9orf72-linked arginine-rich dipeptide repeats aggravate pathological phase separation of G3BP1

Nerom

Ahmed

Lázár

et al. 2023

Preprint

View full text Add to dashboard Cite

Ras GTPase-activating protein-binding protein 1 (G3BP1) is the key protein driving the formation of cytoplasmic stress granules (SGs) by liquid-liquid phase separation (LLPS). It is a switch-like protein held in a closed and inactive state by intramolecular electrostatic interactions competitively opened by RNA, activating the protein and initiating its LLPS. Here we show that C9orf72-derived arginine-rich dipeptide repeats PR30 and GR30 (R-DPRs) present in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), also bind to G3BP1, switching it to an LLPS-competent open state much more effectively than RNA. Whereas RNA binds G3BP1 with micromolar affinity, and cannot initiate LLPS without crowding agents, R-DPRs exhibit a thousand-fold stronger binding to G3BP1, eliciting rapid LLPS even without crowding. The pathogenic effect of R-DPRs is also underscored by the slow transition of R-DPR-G3BP1 liquid droplets to aggregated, ThS-positive states that can recruit the ALS-linked protein hnRNPA2. Deletion constructs and molecular simulations show that R-DPR binding and LLPS are mediated via binding through the negatively charged intrinsically disordered region 1 (IDR1) of the protein, allosterically regulated by the positively charged IDR3. Bioinformatic analyses point to the strong mechanistic parallels of these effects with the interaction of R-DPRs with nuclear nucleophosmin (NPM1) and also suggest that R-DPRs also interact with many other similar nucleolar and stress-granule proteins, extending the underlying mechanism of R-DPR toxicity in cells.

show abstract

Application of polystyrene sulfonate (PSS) for inhibiting toxicity of ALS/FTD-linked dipeptide repeats

Bratek‐Skicki

Ahmed

Peeters

et al. 2023

Preprint

View full text Add to dashboard Cite

The expansion of GGGGCC (G4C2) repeats in the noncoding region of C9orf72 is the most common genetic cause of familial and sporadic amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The repeat region is translated into five different dipeptide repeats (DPRs), of which the arginine-rich DPRs (R-DPRs) poly-GR (GRn) and poly-PR (PRn) are highly neurotoxic and are probably primarily responsible for the disease. Here, we characterized the protective effect against R-DPR toxicity of polystyrene sulfonate (PSS), an FDA-approved drug applied in hyperkalemia, in biochemical, cellular, and animal models of ALS/FTD. We found that PSS, in a length-dependent manner, interacts very tightly with R-DPRs, and releases their bound RNA in R-DPR - RNA mixtures. PSS significantly influences the liquid-liquid phase separation (LLPS) of R-DPRs elicited by RNA and reduces their ensuing cell toxicity in Neuro2a cells. PSS is cell penetrable, and it is also effective in countering the toxicity of R-DPRs in zebrafish embryos. Except for the longest (n = 340) variant, PSS is toxic neither to cells nor to mice upon intracerebroventricular injection up to 1 mM concentration. Our results suggest that its polymeric nature endows PSS with an advantageous effect in C9-ALS/FTD and offers a possible remedy against this debilitating neurodegenerative disease.

show abstract

Aberrant Phase Separation is a Common Killing Strategy of Positively Charged Peptides in Biology and Human Disease

Cited by 6 publications

References 0 publications

Charge-Patterned Disordered Peptides Tune Intracellular Phase Separation in Bacteria

Charge-Patterned Disordered Peptides Tune Intracellular Phase Separation in Bacteria

C9orf72-linked arginine-rich dipeptide repeats aggravate pathological phase separation of G3BP1

Application of polystyrene sulfonate (PSS) for inhibiting toxicity of ALS/FTD-linked dipeptide repeats

Contact Info

Product

Resources

About