Introducing protein deamidation: Landmark discoveries, societal outreach, and tentative priming workflow to address deamidation.

Our current knowledge on protein deamidation results from a journey that started almost 100 years ago, when a handful of researchers first described the non-enzymatic "desamidation" of glutamine, and the effect of different anions on the catalytic rate of the reaction. Since then, the field has tremendously expended and now finds outreach in very diverse areas. In light of all the recent articles published in these areas, it seemed timely to propose an integrated review on the subject, including a short historical overview of the landmark discoveries in the field, highlighting the current global positioning of protein deamidation in biology and non-biology fields, and concluding with a workflow for those asking if a protein can deamidate, and identify the residues involved.

1D continuous gel electrophoresis composition for the separation of deamidated proteins.

Deamidation is a spontaneous modification of peptides and proteins that has potent repercussions on their activity and stability in vivo and in vitro. Being able to implement easy techniques to detect and quantify protein deamidation is a major goal in this field. Here we focus on electrophoretic methods that can be deployed to assess protein deamidation.

Improved Electrophoretic Separation to Assist the Monitoring of Bcl-xL Post-Translational Modifications.

Bcl-x is an oncogene of which the survival functions are finely tuned by post-translational modifications (PTM). Within the Bcl-2 family of proteins, Bcl-x shows unique eligibility to deamidation, a time-related spontaneous reaction. Deamidation is still a largely overlooked PTM due to a lack of easy techniques to monitor Asn→Asp/IsoAsp conversions or Glu→Gln conversions.

Bcl-x deamidation and cancer: Charting the fame trajectories of legitimate child and hidden siblings.

Bcl-2 family proteins control programmed cell death through a complex network of interactions within and outside of this family, that are modulated by post-translational modifications (PTM). Bcl-x, an anti-apoptotic member of this family, is overexpressed in a number of cancers, plays an important role in tumorigenesis and is correlated with drug resistance. Bcl-x is susceptible to a number of different PTMs.

Synthetic toxic Aβ oligomers can assemble in different morphologies.

Background: Alzheimer's disease is the most common neurodegenerative disease associated with aggregation of Aβ peptides. Aβ toxicity is mostly related to the capacity of intermediate oligomers to disrupt membrane integrity. We previously expressed Aβ in a eukaryotic cellular system and selected synthetic variants on their sole toxicity.

Structure/Function Analysis of Protein-Protein Interactions Developed by the Yeast Pih1 Platform Protein and Its Partners in Box C/D snoRNP Assembly.

In eukaryotes, nucleotide post-transcriptional modifications in RNAs play an essential role in cell proliferation by contributing to pre-ribosomal RNA processing, ribosome assembly and activity. Box C/D small nucleolar ribonucleoparticles catalyze site-specific 2'-O-methylation of riboses, one of the most prevalent RNA modifications. They contain one guide RNA and four core proteins and their in vivo assembly requires numerous factors including (HUMAN/Yeast) BCD1/Bcd1p, NUFIP1/Rsa1p, ZNHIT3/Hit1p, the R2TP complex composed of protein PIH1D1/Pih1p and RPAP3/Tah1p that bridges the R2TP complex to the HSP90/Hsp82 chaperone and two AAA+ ATPases.

Combining native MS approaches to decipher archaeal box H/ACA ribonucleoprotein particle structure and activity.

Site-specific isomerization of uridines into pseudouridines in RNAs is catalyzed either by stand-alone enzymes or by box H/ACA ribonucleoprotein particles (sno/sRNPs). The archaeal box H/ACA sRNPs are five-component complexes that consist of a guide RNA and the aCBF5, aNOP10, L7Ae, and aGAR1 proteins. In this study, we performed pairwise incubations of individual constituents of archaeal box H/ACA sRNPs and analyzed their interactions by native MS to build a 2D-connectivity map of direct binders.

Interaction of Aβ(1-42) amyloids with lipids promotes "off-pathway" oligomerization and membrane damage.

The toxicity of amyloids, as Aβ(1-42) involved in Alzheimer disease, is a subject under intense scrutiny. Many studies link their toxicity to the existence of various intermediate structures prior to fiber formation and/or their specific interaction with membranes. In this study we focused on the interaction between membrane models and Aβ(1-42) peptides and variants (L34T, mG37C) produced in E.

A structure-toxicity study of Aß42 reveals a new anti-parallel aggregation pathway.

Amyloid beta (Aβ) peptides produced by APP cleavage are central to the pathology of Alzheimer's disease. Despite widespread interest in this issue, the relationship between the auto-assembly and toxicity of these peptides remains controversial. One intriguing feature stems from their capacity to form anti-parallel ß-sheet oligomeric intermediates that can be converted into a parallel topology to allow the formation of protofibrillar and fibrillar Aβ.

High-resolution structural analysis shows how Tah1 tethers Hsp90 to the R2TP complex.

The ubiquitous Hsp90 chaperone participates in snoRNP and RNA polymerase assembly through interaction with the R2TP complex. This complex includes the proteins Tah1, Pih1, Rvb1, and Rvb2. Tah1 bridges Hsp90 to R2TP.

Assessment of human Nter and Cter BRCA1 mutations using growth and localization assays in yeast.

A large number of missense mutations have been identified within the tumor suppressor gene BRCA1. Most of them, called "variants of unknown significance" (VUS), cannot be classified as pathogenic or neutral by genetic methods, which complicates their cancer risk assessment. Functional assays have been developed to circumvent this uncertainty.