Prediction of protein function by combining phylogenetic tree and mathematical inference

Many major protein–protein interaction networks are maintained by ‘hub’ proteins with multiple binding partners, where interactions are often facilitated by intrinsically disordered protein regions that undergo post-translational modifications, such as phosphorylation. Phosphorylation can directly affect protein function and control recognition by proteins that ‘read’ the phosphorylation code, re-wiring the interactome. The eukaryotic 14-3-3 proteins recognizing multiple phosphoproteins nicely exemplify these concepts. Although recent studies established the biochemical and structural basis for the interaction of the 14-3-3 dimers with several phosphorylated clients, understanding their assembly with partners phosphorylated at multiple sites represents a challenge. Suboptimal sequence context around the phosphorylated residue may reduce binding affinity, resulting in quantitative differences for distinct phosphorylation sites, making hierarchy and priority in their binding rather uncertain. Recently, Stevers et al. [Biochemical Journal (2017) 474: 1273–1287] undertook a remarkable attempt to untangle the mechanism of 14-3-3 dimer binding to leucine-rich repeat kinase 2 (LRRK2) that contains multiple candidate 14-3-3-binding sites and is mutated in Parkinson's disease. By using the protein-peptide binding approach, the authors systematically analyzed affinities for a set of LRRK2 phosphopeptides, alone or in combination, to a 14-3-3 protein and determined crystal structures for 14-3-3 complexes with selected phosphopeptides. This study addresses a long-standing question in the 14-3-3 biology, unearthing a range of important details that are relevant for understanding binding mechanisms of other polyvalent proteins.

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The challenge of detecting modifications on proteins

Essays in Biochemistry ◽

10.1042/ebc20190055 ◽

2020 ◽

Vol 64 (1) ◽

pp. 135-153 ◽

Cited By ~ 1

Author(s):

Lauren Elizabeth Smith ◽

Adelina Rogowska-Wrzesinska

Keyword(s):

Mass Spectrometry ◽

Protein Function ◽

Chemical Properties ◽

Lysine Acetylation ◽

Mass Determination ◽

Post Translational Modifications ◽

Site Specific ◽

The Common

Abstract Post-translational modifications (PTMs) are integral to the regulation of protein function, characterising their role in this process is vital to understanding how cells work in both healthy and diseased states. Mass spectrometry (MS) facilitates the mass determination and sequencing of peptides, and thereby also the detection of site-specific PTMs. However, numerous challenges in this field continue to persist. The diverse chemical properties, low abundance, labile nature and instability of many PTMs, in combination with the more practical issues of compatibility with MS and bioinformatics challenges, contribute to the arduous nature of their analysis. In this review, we present an overview of the established MS-based approaches for analysing PTMs and the common complications associated with their investigation, including examples of specific challenges focusing on phosphorylation, lysine acetylation and redox modifications.

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Sequencing Analysis and Phylogenetic Tree of HPV Isolated from Breast Cancer Patients at Thi-Qar Province/Iraq

10.32792/utq/utjsci/vol7/2/10 ◽

2020 ◽

pp. 37-40

Keyword(s):

Nucleotide Sequence ◽

Phylogenetic Tree ◽

Evolutionary Relationship ◽

Nucleotide Sequencing ◽

Sequencing Analysis ◽

Breast Cancer Patients ◽

The North ◽

Formalin Fixed Paraffin ◽

Formalin Fixed Paraffin Embedded ◽

History Of

Genetic variety examination has demonstrated fundamental to the understanding of the epidemiological and developmental history of Papillomavirus (HPV), for the development of accurate diagnostic tests and for efficient vaccine design. The HPV nucleotide diversity has been investigated widely among high-risk HPV types. To make the nucleotide sequence of HPV and do the virus database in Thi-Qar province, and compare sequences of our isolates with previously described isolates from around the world and then draw its phylogenetic tree, this study done. A total of 6 breast formalin-fixed paraffin-embedded (FFPE) of the female patients were included in the study, divided as 4 FFPE malignant tumor and 2 FFPE of benign tumor. The PCR technique was implemented to detect the presence of HPV in breast tissue, and the real-time PCR used to determinant HPV genotypes, then determined a complete nucleotide sequence of HPV of L1 capsid gene, and draw its phylogenetic tree. The nucleotide sequencing finding detects a number of substitution mutation (SNPs) in (L1) gene, which have not been designated before, were identified once in this study population, and revealed that the HPV16 strains have the evolutionary relationship with the South African race, while, the HPV33 and HPV6 showing the evolutionary association with the North American and East Asian race, respectively.

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Connecting human disease phenotype to genetic mutation and protein function: A modular data mining short course with an independent project sequence for lecture or lab

10.1534/gsaprep.2018.005 ◽

2018 ◽

Author(s):

Janet M. Murray ◽

Heather E. Driscoll ◽

Kara Pivarski

Keyword(s):

Data Mining ◽

Protein Function ◽

Human Disease ◽

Genetic Mutation ◽

Disease Phenotype ◽

Short Course ◽

Modular Data

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Spatial localization of unknown proteins in the endoplasmic reticulum predicts functions

Clinical & Investigative Medicine ◽

10.25011/cim.v30i4.2858 ◽

2007 ◽

Vol 30 (4) ◽

pp. 84

Author(s):

Michael D. Jain ◽

Hisao Nagaya ◽

Annalyn Gilchrist ◽

Miroslaw Cygler ◽

John J.M. Bergeron

Keyword(s):

Endoplasmic Reticulum ◽

Protein Folding ◽

Protein Synthesis ◽

Protein Function ◽

Protein Translocation ◽

Spatial Localization ◽

Predict Protein Function ◽

Insight Into ◽

Soluble Fractions ◽

Er Membrane

Protein synthesis, folding and degradation functions are spatially segregated in the endoplasmic reticulum (ER) with respect to the membrane and the ribosome (rough and smooth ER). Interrogation of a proteomics resource characterizing rough and smooth ER membranes subfractionated into cytosolic, membrane, and soluble fractions gives a spatial map of known proteins involved in ER function. The spatial localization of 224 identified unknown proteins in the ER is predicted to give insight into their function. Here we provide evidence that the proteomics resource accurately predicts the function of new proteins involved in protein synthesis (nudilin), protein translocation across the ER membrane (nicalin), co-translational protein folding (stexin), and distal protein folding in the lumen of the ER (erlin-1, TMX2). Proteomics provides the spatial localization of proteins and can be used to accurately predict protein function.

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Coaction of Electrostatic and Hydrophobic Interactions: Dynamic Constraints on Disordered TrkA Juxtamembrane Domain

10.26434/chemrxiv.9847190 ◽

2019 ◽

Author(s):

Zichen Wang ◽

Huaxun Fan ◽

Xiao Hu ◽

John Khamo ◽

Jiajie Diao ◽

...

Keyword(s):

Single Molecule ◽

Protein Function ◽

Hydrophobic Interactions ◽

Transmembrane Helix ◽

Point Mutations ◽

Salt Bridge ◽

Receptor Activation ◽

Membrane Dynamics ◽

Juxtamembrane Domain ◽

Joint Work

<p>The receptor tyrosine kinase family transmits signals into cell via a single transmembrane helix and a flexible juxtamembrane domain (JMD). Membrane dynamics makes it challenging to study the structural mechanism of receptor activation experimentally. In this study, we employ all-atom molecular dynamics with Highly Mobile Membrane-Mimetic to capture membrane interactions with the JMD of tropomyosin receptor kinase A (TrkA). We find that PIP<sub>2 </sub>lipids engage in lasting binding to multiple basic residues and compete with salt bridge within the peptide. We discover three residues insertion into the membrane, and perturb it through computationally designed point mutations. Single-molecule experiments indicate the contribution from hydrophobic insertion is comparable to electrostatic binding, and in-cell experiments show that enhanced TrkA-JMD insertion promotes receptor ubiquitination. Our joint work points to a scenario where basic and hydrophobic residues on disordered domains interact with lipid headgroups and tails, respectively, to restrain flexibility and potentially modulate protein function.</p>

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