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Lundstrom, K.

Publications and source records attributed to Lundstrom, K..

13 recordsLinked to original sources

Methuselah Proteins in Longevity: Unraveling Their Impact Through Mathematical Genomics

This study provides a quantitative and comprehensive analysis of 18 Methuselah (mth) protein variants from fruit flies, focusing on their evolutionary relationships, structural features, and functional roles in aging and longevity. Phylogenetic analysis identified two major clades of mth proteins, with the first clade indicating conserved functions across Drosophila species and the second clade reflecting gene duplication and diversification. The study found five distinct functional subclasses of mth proteins through amino acid frequency and poly-string analyses, linked to their structural diversity and role in longevity. Structural topology and post-translational modifications reveal similarities with G-protein-coupled receptors (GPCRs), suggesting that mth proteins are crucial for signal transduction and cellular health. Variability in propeptide cleavage sites and intrinsic protein disorder further highlight adaptive roles in signaling. The findings underscore the importance of a quantitative and comprehensive approach to studying Methuselah genes, offering insights into their functional versatility and evolutionary dynamics. This enhanced quantitative understanding contributes to advancing research on aging and longevity.

genomics↗

Molecular Genomic Insights into Melanoma Associated Proteins PRAME and BAP1

BackgroundMelanoma, a worldwide widespread skin cancer with over 325,000 yearly incidences, demands a thorough understanding of its molecular components to create effective therapeutics. This study looks at the PRAME (cutaneous melanoma-associated antigen) and BAP1 (gene controlling gene-environment interactions) proteins, which are important in melanoma development and are important for understanding the molecular landscape of melanoma. IntroductionWhile playing a crucial role in melanoma, the structural and functional characteristics of PRAME and BAP1 remain unidentified. This work tries to unravel their complexities by investigating conserved residues, sequence invariance, and other molecular characteristics that contribute to their importance in melanoma. Promising therapeutic targets for melanoma therapy are identified by analyzing these proteins at the molecular level. MethodsThe study makes extensive use of bioinformatics methods to analyze PRAME and BAP1, including sequence conservation, inherent disorder, polyglutamic acid presence, and polarity alterations. Established approaches are used to investigate residue changes and their effects on protein folding, aggregation, and interactions. ResultsPRAME and BAP1 conserved residues highlight their critical roles in protein function and interaction. Sequence invariance indicates the possibility of functional relevance and evolutionary conservation. In intrinsically disordered proteins (IDPRs), PRAME has enhanced intrinsic disorder and flexibility, whereas BAP1 has changed disorder-promoting residue sequences. Polyglutamic acid strings are found in both proteins, emphasizing their modulatory involvement in protein interactions. Protein folding and aggregation are influenced by polarity shifts, with a balanced distribution of acidic and basic residues preserving native structures. The ratios and distributions of amino acids, particularly neutral residues, have a profound influence on interactions and gene dysregulation. ConclusionPRAME and BAP1 structural and functional understanding pave the way for diagnostic and tailored treatment options in melanoma. Differences in residue alterations, polarity distributions, and amino acid ratios provide intriguing drug design options. This research contributes to a better knowledge of melanoma-associated two proteins, opening the path for novel diagnostic and therapy techniques in skin cancer and beyond.

bioinformatics↗

Unveiling the Genetic Tapestry: Rare Disease Genomics of Spinal Muscular Atrophy and Phenylketonuria Proteins

Rare diseases, defined by their low prevalence, present significant challenges, including delayed detection, expensive treatments, and limited research. This study delves into the genetic basis of two noteworthy rare diseases in Saudi Arabia: Phenylketonuria (PKU) and Spinal Muscular Atrophy (SMA). PKU, resulting from mutations in the phenylalanine hydroxylase (PAH) gene, exhibits geographical variability and impacts intellectual abilities. SMA, characterized by motor neuron loss, is linked to mutations in the survival of motor neuron 1 (SMN1) gene. Recognizing the importance of unveiling signature genomics in rare diseases, we conducted a quantitative study on PAH and SMN1 proteins of multiple organisms by employing various quantitative techniques to assess genetic variations. The derived signature-genomics contributes to a deeper understanding of these critical genes, paving the way for enhanced diagnostics and treatments for disorders associated with PAH and SMN1.

genomics↗

The Distal-Proximal Relationships Among the Human Moonlighting Proteins: Evolutionary hotspots and Darwinian checkpoints

Moonlighting proteins, known for their ability to perform multiple, often unrelated functions within a single polypeptide chain, challenge the traditional "one gene, one protein, one function" paradigm. As organisms evolved, their genomes remained relatively stable in size, but the introduction of post-translational modifications and sub-strategies like protein promiscuity and intrinsic disorder enabled multifunctionality. Enzymes, in particular, exemplify this phenomenon, engaging in unrelated processes alongside their primary catalytic roles. This study employs a systematic, quantitative informatics approach to shed light on human moonlighting protein sequences. Phylogenetic analyses of human moonlighting proteins are presented, elucidating the distal-proximal relationships among these proteins based on sequence-derived quantitative features. The findings unveil the captivating world of human moonlighting proteins, urging further investigations in the emerging field of moonlighting proteomics, with the potential for significant contributions to our understanding of multifunctional proteins and their roles in diverse cellular processes and diseases.

genomics↗

SARS-CoV-2 NSP14 governs mutational instability and assists in making new SARS-CoV-2 variants

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the rapidly evolving RNA virus behind the COVID-19 pandemic, has spawned numerous variants since its 2019 emergence. The multifunctional NSP14 enzyme, possessing exonuclease and mRNA capping capabilities, serves as a key player. Notably, single and co-occurring mutations within NSP14 significantly influence replication fidelity and drive variant diversification. This study comprehensively examines 120 co-mutations, 68 unique mutations, and 160 conserved residues across NSP14 homologs, shedding light on their implications for phylogenetic patterns, pathogenicity, and residue interactions. Quantitative physicochemical analysis categorizes 3953 NSP14 variants into three clusters, revealing genetic diversity. This research underscores the dynamic nature of SARS-CoV-2 evolution, primarily governed by NSP14 mutations. Understanding these genetic dynamics provides valuable insights for therapeutic and vaccine development.

bioinformatics↗

Biology of Coital Behavior: Looking Through the Lens of Mathematical Genomics

Research has shown that genetics and epigenetics regulate mating behavior across multiple species. Previous studies have generally focused on the signaling pathways involved and spatial distribution of the associated receptors. However a thorough quantitative characterization of the receptors involved may offer deeper insight into mating behavioral patterns. Here oxytocin, arginine-vasopressin 1a, dopamine 1, and dopamine 2 receptors were investigated across 76 vertebrate species. The receptor sequences were characterized by polarity-based randomness, amino acid frequency-based Shannon entropy and Shannon sequence variability, intrinsic protein disorder, binding affinity, stability and pathogenicity of homology-based SNPs, structural and physicochemical features. Hierarchical clustering of species was derived based on structural and physicochemical features of the four receptor sequences separately, which eventually led to proximal relationships among 29 species. Humans were found to be significantly distant phylogenetically from the prairie voles, a representative of monogamous species based on coital behavior. Furthermore, the mouse (polygamous), the prairie deer mouse (polygamous), and the prairie vole (monogamous) although being proximally related (based on quantitative genomics of receptors), differed in their coital behavioral pattern, mostly, due to behavioral epigenetic regulations. This study adds a perspective that receptor genomics does not directly translate to behavioral patterns.

genomics↗

SARS-CoV-2 variants show a gradual declining pathogenicity and pro-inflammatory cytokine stimulation and an increasing antigenic and anti-inflammatory cytokine induction

Hyper-transmissibility with decreased disease severity are typical characteristics of Omicron variant. To understand this phenomenon, we used various bioinformatics approaches to analyze randomly selected genome sequences (one each) of the Gamma, Delta, and Omicron variants submitted to NCBI from 15 to 31 December 2021. We show that: (i) Pathogenicity of SARS-CoV-2 variants decreases in the order: Wuhan > Gamma > Delta > Omicron; however, the antigenic property follows the order: Omicron > Gamma > Wuhan > Delta. (ii) Omicron Spike RBD has lower pathogenicity but higher antigenicity than other variants. (iii) Decreased disease severity by Omicron variant may be due to its decreased pro-inflammatory and IL-6 stimulation and increased IFN-{gamma} and IL-4 induction efficacy. (iv) Mutations in N protein are associated with decreased IL-6 induction and human DDX21-mediated increased IL-4 production in Omicron. (v) Due to mutations, the stability of S, M, N, and E proteins decreases in the order: Omicron > Gamma > Delta > Wuhan. (vi) Stronger Spike RBD-hACE2 binding in Omicron is associated with increased transmissibility. However, the lowest stability of the Omicron Spike protein makes Spike RBD-hACE2 interaction weak for systemic infection and for causing severe disease. Finally (vii), the highest instability of Omicron E protein may also be associated with decreased viral maturation and low viral load leading to less severe disease and faster recovery. Our method may be used for other similar viruses, and these findings will contribute to the understanding of the dynamics of SARS-CoV-2 variants and the management of emerging variants.

bioinformatics↗

An Issue of Concern: Unique Truncated ORF8 Protein Variants of SARS-CoV-2

Open reading frame 8 (ORF8) protein is one of the most evolving accessory proteins in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19). It was previously reported that the ORF8 protein inhibits presentation of viral antigens by the major histocompatibility complex class I (MHC-I) and interacts with host factors involved in pulmonary inflammation. The ORF8 protein assists SARS-CoV-2 to evade immunity and replication. Among many contributing mutations, Q27STOP, a mutation in the ORF8 protein defines the B.1.1.7 lineage of SARS-CoV-2, which is engendering the second wave of COVID-19. In the present study, 47 unique truncated ORF8 proteins (T-ORF8) due to the Q27STOP mutations were identified among 49055 available B.1.1.7 SARS-CoV-2 sequences. The results show that only one of the 47 T-ORF8 variants spread to over 57 geo-locations in North America, and other continents which includes Africa, Asia, Europe and South America. Based on various quantitative features such as amino acid homology, polar/non-polar sequence homology, Shannon entropy conservation, and other physicochemical properties of all specific 47 T-ORF8 protein variants, a collection of nine possible T-ORF8 unique variants were defined. The question of whether T-ORF8 variants work similarly to ORF8 has yet to be investigated. A positive response to the question could exacerbate future COVID-19 waves, necessitating severe containment measures.

bioinformatics↗

Implications Derived from S-Protein Variants of SARS-CoV-2 from Six Continents

Spike (S) proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critical determinants of the infectivity and antigenicity of the virus. Several mutations in the spike protein of SARS-CoV-2 have already been detected, and their effect in immune system evasion and enhanced transmission as a cause of increased morbidity and mortality are being investigated. From pathogenic and epidemiological perspectives, spike proteins are of prime interest to researchers. This study focused on the unique variants of S proteins from six continents Asia, Africa, Europe, Oceania, South America, and North America. In comparison to the other five continents, Africa (29.065%) had the highest percentage of unique S proteins. Notably, only North America had 87% (14046) of the total (16143) specific S proteins available in the NCBI database(across all continents). Based on the amino acid frequency distributions in the S protein variants from all the continents, the phylogenetic relationship implies that unique S proteins from North America were significantly different from those of the other five continents. Overtime, the unique variants originating from North America are most likely to spread to the other geographic locations through international travel or naturally by emerging mutations. Hence it is suggested that restriction of international travel should be considered, and massive vaccination as an utmost measure to combat the spread of COVID-19 pandemic. It is also further suggested that the efficacy of existing vaccines and future vaccine development must be reviewed with careful scrutiny, and if needed, further re-engineered based on requirements dictated by new emerging S protein variants.

bioinformatics↗

Variability of Accessory Proteins Rules the SARS-CoV-2 Pathogenicity

The coronavirus disease 2019 (COVID-19) is caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) which is pandemic with an estimated fatality rate less than 1% is ongoing. SARS-CoV-2 accessory proteins ORF3a, ORF6, ORF7a, ORF7b, ORF8, and ORF10 with putative functions to manipulate host immune mechanisms such as interferons, immune signaling receptor NLRP3 (NOD-, LRR-, and pyrin domain-containing 3) inflammasome, inflammatory cytokines such as interleukin 1{beta} (IL-1{beta}) are critical in COVID-19 pathology. Outspread variations of each of the six accessory proteins of all complete proteomes (available as of October 26, 2020, in the National Center for Biotechnology Information depository) of SARS-CoV-2, were observed across six continents. Across all continents, the decreasing order of percentage of unique variations in the accessory proteins was found to be ORF3a>ORF8>ORF7a>ORF6>ORF10>ORF7b. The highest and lowest unique variations of ORF3a were observed in South America and Oceania, respectively. This finding suggests that the wide variations of accessory proteins seem to govern the pathogenicity of SARS-CoV-2, and consequently, certain propositions and recommendations can be made in the public interest.

bioinformatics↗

Possible transmission flow of SARS-CoV-2 based on ACE2 features

Angiotensin-converting enzyme 2 (ACE2) is the cellular receptor for the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that is engendering the severe coronavirus disease 2019 (COVID-19) pandemic. The spike (S) protein receptor-binding domain (RBD) of SARS-CoV-2 binds to the three sub-domains viz. amino acids (aa) 22-42, aa 79-84, and aa 330-393 of ACE2 on human cells to initiate entry. It was reported earlier that the receptor utilization capacity of ACE2 proteins from different species, such as cats, chimpanzees, dogs, and cattle, are different. A comprehensive analysis of ACE2 receptors of nineteen species was carried out in this study, and the findings propose a possible SARS-CoV-2 transmission flow across these nineteen species.

bioinformatics↗

Notable sequence homology of the ORF10 protein introspects the architecture of SARS-COV-2

The global public health is endangered due to COVID-19 pandemic, which is caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Despite having similar pathology to MERS and SARS-CoV, the infection fatality rate of SARS-CoV-2 is likely lower than 1%. SARS-CoV-2 has been reported to be uniquely characterized by the accessory protein ORF10, which contains eleven cytotoxic T lymphocyte (CTL) epitopes of nine amino acids length each, across various human leukocyte antigen (HLA) subtypes. In this study, all missense mutations found in sequence databases were examined across twnety-two unique SARS-CoV-2 ORF10 variants that could possibly alter viral pathogenicity. Some of these mutations decrease the stability of ORF10, e.g. I4L and V6I were found in the MoRF region of ORF10 which may also possibly contribute to Intrinsic protein disorder. Furthermore, a physicochemical and structural comparative analysis was carried out on SARS-CoV-2 and Pangolin-CoV ORF10 proteins, which share 97.37% amino acid homology. The high degree of physicochemical and structural similarity of ORF10 proteins of SARS-CoV-2 and Pangolin-CoV open questions about the architecture of SARS-CoV-2 due to the disagreement of these two ORF10 proteins over their sub-structure (loop/coil region), solubility, antigenicity and change from the strand to coil at amino acid position 26, where tyrosine is present. Altogether, SARS-CoV-2 ORF10 is a promising pharmaceutical target and a protein which should be monitored for changes which correlate to change pathogenesis and clinical course of COVID-19 infection.

bioinformatics↗

A unique view of SARS-CoV-2 through the lens of ORF8 protein

Immune evasion is one of the unique characteristics of COVID-19 attributed to the ORF8 protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This protein is involved in modulating the host adaptive immunity through downregulating MHC (Major Histocompatibility Complex) molecules and innate immune responses by surpassing the interferon mediated antiviral response of the host. To understand the immune perspective of the host with respect to the ORF8 protein, a comprehensive study of the ORF8 protein as well as mutations possessed by it, is performed. Chemical and structural properties of ORF8 proteins from different hosts, that is human, bat and pangolin, suggests that the ORF8 of SARS-CoV-2 and Bat RaTG13-CoV are very much closer related than that of Pangolin-CoV. Eighty-seven mutations across unique variants of ORF8 (SARS-CoV-2) are grouped into four classes based on their predicted effects. Based on geolocations and timescale of collection, a possible flow of mutations was built. Furthermore, conclusive flows of amalgamation of mutations were endorsed upon sequence similarity and amino acid conservation phylogenies. Therefore, this study seeks to highlight the uniqueness of rapid evolving SARS-CoV-2 through the ORF8.

molecular biology↗