ijms-logo

Journal Browser

Journal Browser

Molecular Mechanisms and Treatment of Infectious Diseases

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Molecular Microbiology".

Deadline for manuscript submissions: closed (28 February 2025) | Viewed by 10003

Special Issue Editor

Special Issue Information

Dear Colleagues,

Infection triggers robust immune reactions aimed at eliminating invading pathogens. These combined innate and adaptive immune responses culminate in the eventual restoration of health in most infected individuals. This intricate process entails the engagement of diverse proteins sourced from the pathogens themselves, signaling molecules and receptors, as well as cytokines and chemokines, all of which have been recognized for their pivotal roles in orchestrating this series of events. Understanding the intricate molecular mechanisms underlying host–pathogen interactions is crucial for developing effective treatments. In this Special Issue, we will target the fundamental molecular processes involved in infectious diseases, highlighting recent advancements in treatment strategies and potential therapeutic options.

Dr. João R. Mesquita
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • infectious diseases
  • host–pathogen
  • infection
  • immune responses

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

19 pages, 5613 KiB  
Article
Proteomic Analysis of Differentially Expressed Proteins in A549 Cells Infected with H9N2 Avian Influenza Virus
by Conghui Zhao, Xiaoxuan Zhang, Huanhuan Wang, Haoxi Qiang, Sha Liu, Chunping Zhang, Jiacheng Huang, Yang Wang, Peilin Li, Xinhui Chen, Ziyi Zhang and Shujie Ma
Int. J. Mol. Sci. 2025, 26(2), 657; https://doi.org/10.3390/ijms26020657 - 14 Jan 2025
Viewed by 3210
Abstract
Influenza A viruses (IAVs) are highly contagious pathogens that cause zoonotic disease with limited availability of antiviral therapies, presenting ongoing challenges to both public health and the livestock industry. Unveiling host proteins that are crucial to the IAV life cycle can help clarify [...] Read more.
Influenza A viruses (IAVs) are highly contagious pathogens that cause zoonotic disease with limited availability of antiviral therapies, presenting ongoing challenges to both public health and the livestock industry. Unveiling host proteins that are crucial to the IAV life cycle can help clarify mechanisms of viral replication and identify potential targets for developing alternative host-directed therapies. Using a four-dimensional (4D), label-free methodology coupled with bioinformatics analysis, we analyzed the expression patterns of cellular proteins that changed following H9N2 virus infection. Compared to the control group, the H9N2 infected group displayed 732 differentially expressed proteins (DEPs), with 298 proteins showing upregulation and 434 proteins showing downregulation. Gene Ontology (GO) functional analysis showed that DEPs were catalog in 11 biological processes, three cellular components, and eight molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that DEPs were involved in processes including cytokine signaling pathways induced by virus infection and protein digestion and absorption. Proteins including TP53, DDX58, and STAT3 were among the top hub proteins in the protein–protein interaction (PPI) analysis, suggesting that these signaling cascades could be essential for the propagation of IAVs. Furthermore, the host protein SNAPIN was chosen to ascertain the accuracy of expression changes identified through a proteomic analysis. The results indicated that SNAPIN was downregulated following infection with IAVs both in vitro and in vivo, which is consistent with the proteomics results, suggesting that SNAPIN may serve as a key regulatory factor in the viral life cycle of IAVs. Our research delineates an extensive interaction map of IAV infection within the A549 cells, facilitating the discovery of pivotal proteins that contribute to the virus’s propagation, potentially offering target candidates to screen for antiviral therapeutics. Full article
(This article belongs to the Special Issue Molecular Mechanisms and Treatment of Infectious Diseases)
Show Figures

Figure 1

28 pages, 4912 KiB  
Article
Characterization of the First Secreted Sorting Nexin Identified in the Leishmania Protists
by Olympia Tziouvara, Marina Petsana, Drosos Kourounis, Amalia Papadaki, Efthimia Basdra, Georgia G. Braliou and Haralabia Boleti
Int. J. Mol. Sci. 2024, 25(7), 4095; https://doi.org/10.3390/ijms25074095 - 7 Apr 2024
Cited by 1 | Viewed by 2111
Abstract
Proteins of the sorting nexin (SNX) family present a modular structural architecture with a phox homology (PX) phosphoinositide (PI)-binding domain and additional PX structural domains, conferring to them a wide variety of vital eukaryotic cell’s functions, from signal transduction to membrane deformation and [...] Read more.
Proteins of the sorting nexin (SNX) family present a modular structural architecture with a phox homology (PX) phosphoinositide (PI)-binding domain and additional PX structural domains, conferring to them a wide variety of vital eukaryotic cell’s functions, from signal transduction to membrane deformation and cargo binding. Although SNXs are well studied in human and yeasts, they are poorly investigated in protists. Herein, is presented the characterization of the first SNX identified in Leishmania protozoan parasites encoded by the LdBPK_352470 gene. In silico secondary and tertiary structure prediction revealed a PX domain on the N-terminal half and a Bin/amphiphysin/Rvs (BAR) domain on the C-terminal half of this protein, with these features classifying it in the SNX-BAR subfamily of SNXs. We named the LdBPK_352470.1 gene product LdSNXi, as it is the first SNX identified in Leishmania (L.) donovani. Its expression was confirmed in L. donovani promastigotes under different cell cycle phases, and it was shown to be secreted in the extracellular medium. Using an in vitro lipid binding assay, it was demonstrated that recombinant (r) LdSNXi (rGST-LdSNXi) tagged with glutathione-S-transferase (GST) binds to the PtdIns3P and PtdIns4P PIs. Using a specific a-LdSNXi antibody and immunofluorescence confocal microscopy, the intracellular localization of endogenous LdSNXi was analyzed in L. donovani promastigotes and axenic amastigotes. Additionally, rLdSNXi tagged with enhanced green fluorescent protein (rLdSNXi-EGFP) was heterologously expressed in transfected HeLa cells and its localization was examined. All observed localizations suggest functions compatible with the postulated SNX identity of LdSNXi. Sequence, structure, and evolutionary analysis revealed high homology between LdSNXi and the human SNX2, while the investigation of protein–protein interactions based on STRING (v.11.5) predicted putative molecular partners of LdSNXi in Leishmania. Full article
(This article belongs to the Special Issue Molecular Mechanisms and Treatment of Infectious Diseases)
Show Figures

Figure 1

18 pages, 2537 KiB  
Article
Differential Ability of Spike Protein of SARS-CoV-2 Variants to Downregulate ACE2
by Yosuke Maeda, Mako Toyoda, Takeo Kuwata, Hiromi Terasawa, Umiru Tokugawa, Kazuaki Monde, Tomohiro Sawa, Takamasa Ueno and Shuzo Matsushita
Int. J. Mol. Sci. 2024, 25(2), 1353; https://doi.org/10.3390/ijms25021353 - 22 Jan 2024
Cited by 3 | Viewed by 2408
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 19 (COVID-19) and employs angiotensin-converting enzyme 2 (ACE2) as the receptor. Although the expression of ACE2 is crucial for cellular entry, we found that the interaction between ACE2 and [...] Read more.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 19 (COVID-19) and employs angiotensin-converting enzyme 2 (ACE2) as the receptor. Although the expression of ACE2 is crucial for cellular entry, we found that the interaction between ACE2 and the Spike (S) protein in the same cells led to its downregulation through degradation in the lysosomal compartment via the endocytic pathway. Interestingly, the ability of the S protein from previous variants of concern (VOCs) to downregulate ACE2 was variant-dependent and correlated with disease severity. The S protein from the Omicron variant, associated with milder disease, exhibited a lower capacity to downregulate ACE2 than that of the Delta variant, which is linked to a higher risk of hospitalization. Chimeric studies between the S proteins from the Delta and Omicron variants revealed that both the receptor-binding domain (RBD) and the S2 subunit played crucial roles in the reduced ACE2 downregulation activity observed in the Omicron variant. In contrast, three mutations (L452R/P681R/D950N) located in the RBD, S1/S2 cleavage site, and HR1 domain were identified as essential for the higher ACE2 downregulation activity observed in the Delta variant compared to that in the other VOCs. Our results suggested that dysregulation of the renin–angiotensin system due to the ACE2 downregulation activity of the S protein of SARS-CoV-2 may play a key role in the pathogenesis of COVID-19. Full article
(This article belongs to the Special Issue Molecular Mechanisms and Treatment of Infectious Diseases)
Show Figures

Figure 1

Review

Jump to: Research

28 pages, 5112 KiB  
Review
Cyclophilin A Regulates Tripartite Motif 5 Alpha Restriction of HIV-1
by Tingting Wang, Daniel Becker, Augustin Penda Twizerimana, Tom Luedde, Holger Gohlke and Carsten Münk
Int. J. Mol. Sci. 2025, 26(2), 495; https://doi.org/10.3390/ijms26020495 - 9 Jan 2025
Viewed by 1226
Abstract
The peptidyl-prolyl isomerase A (PPIA), also known as cyclophilin A (CYPA), is involved in multiple steps of the HIV-1 replication cycle. CYPA regulates the restriction of many host factors by interacting with the CYPA-binding loop on the HIV-1 capsid (CA) surface. TRIM5 (tripartite [...] Read more.
The peptidyl-prolyl isomerase A (PPIA), also known as cyclophilin A (CYPA), is involved in multiple steps of the HIV-1 replication cycle. CYPA regulates the restriction of many host factors by interacting with the CYPA-binding loop on the HIV-1 capsid (CA) surface. TRIM5 (tripartite motif protein 5) in primates is a key species-specific restriction factor defining the HIV-1 pandemic. The incomplete adaptation of HIV-1 to humans is due to the different utilization of CYPA by pandemic and non-pandemic HIV-1. The enzymatic activity of CYPA on the viral core is likely an important reason for regulating the TRIM5 restriction activity. Thus, the HIV-1 capsid and its CYPA interaction may serve as new targets for future anti-AIDS therapeutic agents. This article will describe the species-specificity of the restriction factor TRIM5, understand the role of CYPA in regulating restriction factors in retroviral infection, and discuss important future research issues. Full article
(This article belongs to the Special Issue Molecular Mechanisms and Treatment of Infectious Diseases)
Show Figures

Figure 1

Back to TopTop