scholarly journals The Role of Low Complexity Regions in Protein Interaction Modes: An Illustration in Huntingtin

2021 ◽  
Vol 22 (4) ◽  
pp. 1727
Author(s):  
Kristina Kastano ◽  
Pablo Mier ◽  
Miguel A. Andrade-Navarro
Keyword(s):  
Protein Interaction ◽  
Protein Interactions ◽  
Structural Information ◽  
Low Complexity ◽  
Protein Interaction Data ◽  
Protein Protein Interactions ◽  
Post Translational Modifications ◽  
Evolutionarily Conserved ◽  
And Function

Low complexity regions (LCRs) are very frequent in protein sequences, generally having a lower propensity to form structured domains and tending to be much less evolutionarily conserved than globular domains. Their higher abundance in eukaryotes and in species with more cellular types agrees with a growing number of reports on their function in protein interactions regulated by post-translational modifications. LCRs facilitate the increase of regulatory and network complexity required with the emergence of organisms with more complex tissue distribution and development. Although the low conservation and structural flexibility of LCRs complicate their study, evolutionary studies of proteins across species have been used to evaluate their significance and function. To investigate how to apply this evolutionary approach to the study of LCR function in protein–protein interactions, we performed a detailed analysis for Huntingtin (HTT), a large protein that is a hub for interaction with hundreds of proteins, has a variety of LCRs, and for which partial structural information (in complex with HAP40) is available. We hypothesize that proteins RASA1, SYN2, and KAT2B may compete with HAP40 for their attachment to the core of HTT using similar LCRs. Our results illustrate how evolution might favor the interplay of LCRs with domains, and the possibility of detecting multiple modes of LCR-mediated protein–protein interactions with a large hub such as HTT when enough protein interaction data is available.

Protein Interaction Domains and Post-Translational Modifications: Structural Features and Drug Discovery Applications

2020 ◽  
Vol 27 (37) ◽  
pp. 6306-6355 ◽  
Author(s):  
Marian Vincenzi ◽  
Flavia Anna Mercurio ◽  
Marilisa Leone
Keyword(s):  
Drug Discovery ◽  
Protein Interaction ◽  
Protein Interactions ◽  
Structural Information ◽  
Protein Complexes ◽  
Structural Features ◽  
Protein Protein Interactions ◽  
Modular Architecture ◽  
Post Translational Modifications ◽  
Interaction Domains

Background:: Many pathways regarding healthy cells and/or linked to diseases onset and progression depend on large assemblies including multi-protein complexes. Protein-protein interactions may occur through a vast array of modules known as protein interaction domains (PIDs). Objective:: This review concerns with PIDs recognizing post-translationally modified peptide sequences and intends to provide the scientific community with state of art knowledge on their 3D structures, binding topologies and potential applications in the drug discovery field. Method:: Several databases, such as the Pfam (Protein family), the SMART (Simple Modular Architecture Research Tool) and the PDB (Protein Data Bank), were searched to look for different domain families and gain structural information on protein complexes in which particular PIDs are involved. Recent literature on PIDs and related drug discovery campaigns was retrieved through Pubmed and analyzed. Results and Conclusion:: PIDs are rather versatile as concerning their binding preferences. Many of them recognize specifically only determined amino acid stretches with post-translational modifications, a few others are able to interact with several post-translationally modified sequences or with unmodified ones. Many PIDs can be linked to different diseases including cancer. The tremendous amount of available structural data led to the structure-based design of several molecules targeting protein-protein interactions mediated by PIDs, including peptides, peptidomimetics and small compounds. More studies are needed to fully role out, among different families, PIDs that can be considered reliable therapeutic targets, however, attacking PIDs rather than catalytic domains of a particular protein may represent a route to obtain selective inhibitors.

scholarly journals iProteinDB: an integrative database of Drosophila post-translational modifications

2018 ◽  
Author(s):  
Yanhui Hu ◽  
Richelle Sopko ◽  
Verena Chung ◽  
Romain A. Studer ◽  
Sean D. Landry ◽  
...  
Keyword(s):  
Protein Interactions ◽  
Protein Function ◽  
Large Scale ◽  
Model Organisms ◽  
General Strategy ◽  
Post Translational Modification ◽  
Post Translational Modifications ◽  
Functional Sites ◽  
Evolutionarily Conserved ◽  
And Function

AbstractPost-translational modification (PTM) serves as a regulatory mechanism for protein function, influencing stability, protein interactions, activity and localization, and is critical in many signaling pathways. The best characterized PTM is phosphorylation, whereby a phosphate is added to an acceptor residue, commonly serine, threonine and tyrosine. As proteins are often phosphorylated at multiple sites, identifying those sites that are important for function is a challenging problem. Considering that many phosphorylation sites may be non-functional, prioritizing evolutionarily conserved phosphosites provides a general strategy to identify the putative functional sites with regards to regulation and function. To facilitate the identification of conserved phosphosites, we generated a large-scale phosphoproteomics dataset from Drosophila embryos collected from six closely-related species. We built iProteinDB (https://www.flyrnai.org/tools/iproteindb/), a resource integrating these data with other high-throughput PTM datasets, including vertebrates, and manually curated information for Drosophila. At iProteinDB, scientists can view the PTM landscape for any Drosophila protein and identify predicted functional phosphosites based on a comparative analysis of data from closely-related Drosophila species. Further, iProteinDB enables comparison of PTM data from Drosophila to that of orthologous proteins from other model organisms, including human, mouse, rat, Xenopus laevis, Danio rerio, and Caenorhabditis elegans.

Exploring the role of post-translational modifications on protein–protein interactions with survivin

2013 ◽  
Vol 538 (2) ◽  
pp. 64-70 ◽  
Author(s):  
Rita Nogueira-Ferreira ◽  
Rui Vitorino ◽  
Manuel J. Ferreira-Pinto ◽  
Rita Ferreira ◽  
Tiago Henriques-Coelho
Keyword(s):  
Protein Interactions ◽  
Protein Protein Interactions ◽  
Post Translational Modifications

One Hippo and many masters: differential regulation of the Hippo pathway in cancer

2014 ◽  
Vol 42 (4) ◽  
pp. 816-821 ◽  
Author(s):  
David Romano ◽  
David Matallanas ◽  
Dennie T. Frederick ◽  
Keith T. Flaherty ◽  
Walter Kolch
Keyword(s):  
Protein Interactions ◽  
Hippo Pathway ◽  
Promoter Hypermethylation ◽  
Protein Protein Interactions ◽  
Evolutionarily Conserved ◽  
Or Gene ◽  
Phosphoinositide 3 Kinase ◽  
Ras Isoforms ◽  
The Hippo Pathway

The Hippo/MST2 (mammalian sterile 20-like kinase 2) pathway is a signalling cascade evolutionarily conserved in its structure. Originally described in Drosophila melanogaster as a regulator of organ size, this pathway has greater functions in mammals. Disturbance of mammalian MST2 pathway is associated with tumorigenesis by affecting apoptosis, cell cycle and polarity. In addition, this pathway has been shown to cross-talk with mitogenic pathways at multiple levels. In the present mini-review, we discuss our contribution highlighting the regulation of MST2 signalling by frequently observed oncogenic perturbations affecting mitogenic pathways. In particular, we review the role of RAS isoforms and PI3K (phosphoinositide 3-kinase)/Akt in the regulation of MST2 activity by phosphorylation. We also put the emphasis on RAF-induced control of MST2 signalling by protein–protein interactions. Finally, we recapitulate some of the direct mechanisms, such as ubiquitin-dependent degradation or gene silencing by promoter hypermethylation, involved in MST2 pathway component down-regulation in cancers.

scholarly journals A proline-rich sequence unique to MEK1 and MEK2 is required for raf binding and regulates MEK function.

1995 ◽  
Vol 15 (10) ◽  
pp. 5214-5225 ◽  
Author(s):  
A D Catling ◽  
H J Schaeffer ◽  
C W Reuter ◽  
G R Reddy ◽  
M J Weber
Keyword(s):  
Protein Interactions ◽  
Critical Role ◽  
Phosphorylation Site ◽  
Specific Protein ◽  
Protein Protein Interactions ◽  
Serum Stimulation ◽  
And Function

Mammalian MEK1 and MEK2 contain a proline-rich (PR) sequence that is absent both from the yeast homologs Ste7 and Byr1 and from a recently cloned activator of the JNK/stress-activated protein kinases, SEK1/MKK4. Since this PR sequence occurs in MEKs that are regulated by Raf family enzymes but is missing from MEKs and SEKs activated independently of Raf, we sought to investigate the role of this sequence in MEK1 and MEK2 regulation and function. Deletion of the PR sequence from MEK1 blocked the ability of MEK1 to associate with members of the Raf family and markedly attenuated activation of the protein in vivo following growth factor stimulation. In addition, this sequence was necessary for efficient activation of MEK1 in vitro by B-Raf but dispensable for activation by a novel MEK1 activator which we have previously detected in fractionated fibroblast extracts. Furthermore, we found that a phosphorylation site within the PR sequence of MEK1 was required for sustained MEK1 activity in response to serum stimulation of quiescent fibroblasts. Consistent with this observation, we observed that MEK2, which lacks a phosphorylation site at the corresponding position, was activated only transiently following serum stimulation. Finally, we found that deletion of the PR sequence from a constitutively activated MEK1 mutant rendered the protein nontransforming in Rat1 fibroblasts. These observations indicate a critical role for the PR sequence in directing specific protein-protein interactions important for the activation, inactivation, and downstream functioning of the MEKs.

scholarly journals The Role of Meningococcal Porin B in Protein-Protein Interactions with Host Cells

2018 ◽  
Vol 62 (1) ◽  
pp. 52-58
Author(s):  
E. Káňová ◽  
I. Jiménez-Munguía ◽  
Ľ. Čomor ◽  
Z. Tkáčová ◽  
I. Širochmanová ◽  
...  
Keyword(s):  
Protein Interactions ◽  
Cell Signalling ◽  
Structure And Function ◽  
Host Cells ◽  
Protein Protein Interactions ◽  
Receptor Interactions ◽  
And Function ◽  
Fatal Sepsis ◽  
Porin B

Abstract Neisseria meningitidis is a Gram-negative diplococcus responsible for bacterial meningitis and fatal sepsis. Ligand-receptor interactions are one of the main steps in the development of neuroinvasion. Porin B (PorB), neisserial outer membrane protein (ligand), binds to host receptors and triggers many cell signalling cascades allowing the meningococcus to damage the host cells or induce immune cells responses via the TLR2-dependent mechanisms. In this paper, we present a brief review of the structure and function of PorB.

scholarly journals Applications of In-Cell NMR in Structural Biology and Drug Discovery

2019 ◽  
Vol 20 (1) ◽  
pp. 139 ◽  
Author(s):  
CongBao Kang
Keyword(s):  
Drug Discovery ◽  
Conformational Changes ◽  
Protein Interactions ◽  
Mammalian Cells ◽  
Structural Information ◽  
Living Cells ◽  
Bacterial Cells ◽  
Protein Protein Interactions ◽  
Nmr Studies ◽  
Post Translational Modifications

In-cell nuclear magnetic resonance (NMR) is a method to provide the structural information of a target at an atomic level under physiological conditions and a full view of the conformational changes of a protein caused by ligand binding, post-translational modifications or protein–protein interactions in living cells. Previous in-cell NMR studies have focused on proteins that were overexpressed in bacterial cells and isotopically labeled proteins injected into oocytes of Xenopus laevis or delivered into human cells. Applications of in-cell NMR in probing protein modifications, conformational changes and ligand bindings have been carried out in mammalian cells by monitoring isotopically labeled proteins overexpressed in living cells. The available protocols and successful examples encourage wide applications of this technique in different fields such as drug discovery. Despite the challenges in this method, progress has been made in recent years. In this review, applications of in-cell NMR are summarized. The successful applications of this method in mammalian and bacterial cells make it feasible to play important roles in drug discovery, especially in the step of target engagement.

Domain-Based Prediction and Analysis of Protein-Protein Interactions

2009 ◽  
pp. 29-44 ◽  
Author(s):  
Tatsuya Akutsu ◽  
Morihiro Hayashida
Keyword(s):  
Protein Interaction ◽  
Protein Interactions ◽  
Protein Domains ◽  
Interaction Model ◽  
Protein Interaction Data ◽  
Protein Protein Interactions ◽  
Scale Free ◽  
Protein Protein Interaction ◽  
Domain Interactions ◽  
Protein Sequence Data

Many methods have been proposed for inference of protein-protein interactions from protein sequence data. This chapter focuses on methods based on domain-domain interactions, where a domain is defined as a region within a protein that either performs a specific function or constitutes a stable structural unit. In these methods, the probabilities of domain-domain interactions are inferred from known protein-protein interaction data and protein domain data, and then prediction of interactions is performed based on these probabilities and contents of domains of given proteins. This chapter overviews several fundamental methods, which include association method, expectation maximization-based method, support vector machine-based method, and linear programmingbased method. This chapter also reviews a simple evolutionary model of protein domains, which yields a scalefree distribution of protein domains. By combining with a domain-based protein interaction model, a scale-free distribution of protein-protein interaction networks is also derived.

scholarly journals Emerging Concepts and Functions of Autophagy as a Regulator of Synaptic Components and Plasticity

Cells ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 34 ◽  
Author(s):  
YongTian Liang
Keyword(s):  
Synaptic Plasticity ◽  
Protein Interactions ◽  
Synaptic Function ◽  
Synaptic Proteins ◽  
Protein Protein Interactions ◽  
Neuronal Function ◽  
And Function ◽  
Cellular Components ◽  
Neuronal Autophagy

Protein homeostasis (proteostasis) is crucial to the maintenance of neuronal integrity and function. As the contact sites between neurons, synapses rely heavily on precisely regulated protein-protein interactions to support synaptic transmission and plasticity processes. Autophagy is an effective degradative pathway that can digest cellular components and maintain cellular proteostasis. Perturbations of autophagy have been implicated in aging and neurodegeneration due to a failure to remove damaged proteins and defective organelles. Recent evidence has demonstrated that autophagosome formation is prominent at synaptic terminals and neuronal autophagy is regulated in a compartment-specific fashion. Moreover, synaptic components including synaptic proteins and vesicles, postsynaptic receptors and synaptic mitochondria are known to be degraded by autophagy, thereby contributing to the remodeling of synapses. Indeed, emerging studies indicate that modulation of autophagy may be required for different forms of synaptic plasticity and memory formation. In this review, I will discuss our current understanding of the important role of neuronal/synaptic autophagy in maintaining neuronal function by degrading synaptic components and try to propose a conceptual framework of how the degradation of synaptic components via autophagy might impact synaptic function and contribute to synaptic plasticity.

scholarly journals Time-lapsed proteomics reveals a role for the novel protein, SNED1, in modulating ECM composition and protein folding

2022 ◽  
Author(s):  
Fred Lee ◽  
Xinhao Shao ◽  
Yu Gao ◽  
Alexandra Naba
Keyword(s):  
Protein Interactions ◽  
Dynamic Range ◽  
Structural Information ◽  
Limited Proteolysis ◽  
The Novel ◽  
Protein Protein Interactions ◽  
Sequence Coverage ◽  
Post Translational Modifications ◽  
Ecm Proteins ◽  
Broad Dynamic Range

The extracellular matrix (ECM) is a complex and dynamic meshwork of proteins providing structural support to cells. It also provides biochemical signals governing cellular processes including proliferation and migration. Alterations of ECM structure and/or composition has been shown to lead to, or accompany, many pathological processes including cancer and fibrosis. To understand how the ECM contributes to diseases, we first need to obtain a comprehensive characterization of the ECM of tissues and of its changes during disease progression. Over the past decade, mass-spectrometry-based proteomics has become the state-of-the-art method to profile the protein composition of ECMs. However, existing methods do not fully capture the broad dynamic range of protein abundance in the ECM, nor do they permit to achieve the high coverage needed to gain finer biochemical information, including the presence of isoforms or post-translational modifications. In addition, broadly adopted proteomic methods relying on extended trypsin digestion do not provide structural information on ECM proteins, yet, gaining insights into ECM protein structure is critical to better understanding protein functions. Here, we present the optimization of a time-lapsed proteomic method using limited proteolysis of partially denatured samples and the sequential release of peptides to achieve superior sequence coverage as compared to standard ECM proteomic workflow. Exploiting the spatio-temporal resolution of this method, we further demonstrate how 3-dimensional time-lapsed peptide mapping can identify protein regions differentially susceptible to trypsin and can thus identify sites of post-translational modifications, including protein-protein interactions. We further illustrate how this approach can be leveraged to gain insight on the role of the novel ECM protein SNED1 in ECM homeostasis. We found that the expression of SNED1 expression by mouse embryonic fibroblasts results in the alteration of overall ECM composition and the sequence coverage of certain ECM proteins, raising the possibility that SNED1 could modify accessibility to trypsin by engaging in protein-protein interactions.

Sign in / Sign up

Export Citation Format

Share Document