Signal Peptide Variants in Inherited Retinal Diseases: A Multi-Institutional Case Series

Jimenez, Hiram J; Procopio, Rebecca; Thuma, Tobin B. T.; Marra, Molly; Izquierdo, Natalio J.; Klufas, Michael A.; Nagiel, Aaron; Pennesi, Mark E.; Pulido, José S.

doi:10.3390/ijms232113361

Cited by 3 publications

(1 citation statement)

References 34 publications

(47 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Translocation from the cytoplasm into the ER requires a functional amino terminal signal peptide, which needs to efficiently interact with the Sec61 translocon complex, open the channel to initiate translocation, and be available for the proper cleavage by the peptidase. Therefore, mutations that disrupt the hydrophobic core of the SP have a deleterious effect on translocation efficiency in vivo and in vitro (Jimenez et al, 2022). Here, we found that the translocation deficient ppαF mutant, in which the alanine 13 located on the hydrophobic core is replaced by a glutamic acid, significantly impaired the strength and presumably the specificity of the interaction between the signal peptide and the Sec61 complex.…”

Section: Discussionmentioning

confidence: 99%

Characterization of the interaction between the Sec61 translocon complex and ppαF using optical tweezers

Robeson,

Casanova‐Morales,

Burgos‐Bravo

et al. 2024

Protein Science

View full text Add to dashboard Cite

The Sec61 translocon allows the translocation of secretory preproteins from the cytosol to the endoplasmic reticulum lumen during polypeptide biosynthesis. These proteins possess an N‐terminal signal peptide (SP) which docks at the translocon. SP mutations can abolish translocation and cause diseases, suggesting an essential role for this SP/Sec61 interaction. However, a detailed biophysical characterization of this binding is still missing. Here, optical tweezers force spectroscopy was used to characterize the kinetic parameters of the dissociation process between Sec61 and the SP of prepro‐alpha‐factor. The unbinding parameters including off‐rate constant and distance to the transition state were obtained by fitting rupture force data to Dudko–Hummer–Szabo models. Interestingly, the translocation inhibitor mycolactone increases the off‐rate and accelerates the SP/Sec61 dissociation, while also weakening the interaction. Whereas the translocation deficient mutant containing a single point mutation in the SP abolished the specificity of the SP/Sec61 binding, resulting in an unstable interaction. In conclusion, we characterize quantitatively the dissociation process between the signal peptide and the translocon, and how the unbinding parameters are modified by a translocation inhibitor.

show abstract

Section: Discussionmentioning

confidence: 99%

Characterization of the interaction between the Sec61 translocon complex and ppαF using optical tweezers

Robeson,

Casanova‐Morales,

Burgos‐Bravo

et al. 2024

Protein Science

View full text Add to dashboard Cite

show abstract

SignalP: The Evolution of a Web Server

Nielsen,

Teufel,

Brunak

et al. 2024

Protein Bioinformatics

View full text Add to dashboard Cite

Systematic assessment of the contribution of structural variants to inherited retinal diseases

Wen

Wang

Qian

et al. 2023

Human Molecular Genetics

View full text Add to dashboard Cite

Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined was subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY, and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these four algorithms were included for further analysis. AnnotSV was used to annotate these SVs. SVs that overlap with known IRD-associated genes were examined with sequencing coverage, junction reads, and discordant read pairs. PCR followed by Sanger sequencing was used to further confirm the SVs and identify the breakpoints. Segregation of the candidate pathogenic alleles with the disease was performed when possible. In total, sixteen candidate pathogenic SVs were identified in sixteen families, including deletions and inversions, representing 2.1% of patients with previously unsolved IRDs. Autosomal dominant, autosomal recessive, and X-linked inheritance of disease-causing SVs were observed in 12 different genes. Among these, SVs in CLN3, EYS, PRPF31 were found in multiple families. Our study suggests that the contribution of SVs detected by short-read WGS is about 0.25% of our IRD patient cohort and is significantly lower than that of single nucleotide changes and small insertions and deletions.

show abstract

Signal Peptide Variants in Inherited Retinal Diseases: A Multi-Institutional Case Series

Cited by 3 publications

References 34 publications

Characterization of the interaction between the Sec61 translocon complex and ppαF using optical tweezers

Characterization of the interaction between the Sec61 translocon complex and ppαF using optical tweezers

SignalP: The Evolution of a Web Server

Systematic assessment of the contribution of structural variants to inherited retinal diseases

Contact Info

Product

Resources

About