Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
6.7
4.2
Journals
JoF
Special Issues
Molecular and Genetic Tools for Studying Cryptococcus spp.
share announcement

Molecular and Genetic Tools for Studying Cryptococcus spp.

A special issue of Journal of Fungi (ISSN 2309-608X). This special issue belongs to the section "Fungal Genomics, Genetics and Molecular Biology".

Deadline for manuscript submissions: closed (31 July 2021) | Viewed by 31120

Special Issue Editor

Prof. Dr. Brian L. Wickes

E-Mail Website
Guest Editor
Department of Microbiology, Immunology, and Molecular Genetics, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
Interests: molecular diagnostics; fungal pathogenesis; Cryptococcus neoformans morphology and development; Candida glabrata and Candida auris drug resistance
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear colleagues,

Cryptococcosis, caused by C. neoformans and C. gattii, is a major fungal disease of HIV and other immunosuppressed patients. The identification of the sexual phase of Cryptococcus neoformans in 1975 provided the first tool for studying this fungus. Fifteen years later, transformation laid the foundation for the molecular genetic era of Cryptococcus research. Saccharomyces cerevisiae genetic and molecular tools have served as a road map for the development of crucial research tools for studying all fungi. Unfortunately, medically important fungi have proven difficult to manipulate with S. cerevisiae efficiency, and Cryptococcus is no exception. However, through extraordinary community effort and collaboration, the genomes of multiple Cryptococcus species and strains have been sequenced which, combined with existing genetic and transformation systems, have paved the way for the development of more sophisticated molecular tools. Cryptococcus is now one of the most molecularly amenable human fungal pathogens. The goal of this Special Issue is to provide an update on the most current molecular and genetic methodologies for studying Cryptococcus through reviews and original research articles.

Prof. Dr. Brian L. Wickes
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. Journal of Fungi is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). 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

  • Cryptococcosis
  • Cryptococcus spp.
  • Molecular and genetic methodologies

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 polices can be found here.

Published Papers (8 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

Jump to: Review

13 pages, 2322 KiB  
Article
Simplified All-In-One CRISPR-Cas9 Construction for Efficient Genome Editing in Cryptococcus Species
by Ping Zhang, Yu Wang, Chenxi Li, Xiaoyu Ma, Lan Ma and Xudong Zhu
J. Fungi 2021, 7(7), 505; https://doi.org/10.3390/jof7070505 - 24 Jun 2021
Cited by 7 | Viewed by 3685
Abstract
Cryptococcus neoformans and Cryptococcus deneoformans are opportunistic fungal pathogens found worldwide that are utilized to reveal mechanisms of fungal pathogenesis. However, their low homologous recombination frequency has greatly encumbered genetic studies. In preliminary work, we described a ‘suicide’ CRISPR-Cas9 system for use in [...] Read more.
Cryptococcus neoformans and Cryptococcus deneoformans are opportunistic fungal pathogens found worldwide that are utilized to reveal mechanisms of fungal pathogenesis. However, their low homologous recombination frequency has greatly encumbered genetic studies. In preliminary work, we described a ‘suicide’ CRISPR-Cas9 system for use in the efficient gene editing of C. deneoformans, but this has not yet been used in the C. neoformans strain. The procedures involved in constructing vectors are time-consuming, whether they involve restriction enzyme-based cloning of donor DNA or the introduction of a target sequence into the gRNA expression cassette via overlap PCR, as are sophisticated, thus impeding their widespread application. Here, we report the optimized and simplified construction method for all-in-one CRISPR-Cas9 vectors that can be used in C. neoformans and C. deneoformans strains respectively, named pNK003 (Genbank: MW938321) and pRH003 (Genbank: KX977486). Taking several gene manipulations as examples, we also demonstrate the accuracy and efficiency of the new simplified all-in-one CRISPR-Cas9 genome editing tools in both Serotype A and Serotype D strains, as well as their ability to eliminate Cas9 and gDNA cassettes after gene editing. We anticipate that the availability of new vectors that can simplify and streamline the technical steps for all-in-one CRISPR-Cas9 construction could accelerate genetic studies of the Cryptococcus species. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
►▼ Show Figures

Figure 1

12 pages, 1652 KiB  
Article
Influence of Galectin-3 on the Innate Immune Response during Experimental Cryptococcosis
by Caroline Patini Rezende, Patricia Kellen Martins Oliveira Brito, Thiago Aparecido Da Silva, Andre Moreira Pessoni, Leandra Naira Zambelli Ramalho and Fausto Almeida
J. Fungi 2021, 7(6), 492; https://doi.org/10.3390/jof7060492 - 20 Jun 2021
Cited by 2 | Viewed by 2438
Abstract
Cryptococcus neoformans, the causative agent of cryptococcosis, is the primary fungal pathogen that affects the immunocompromised individuals. Galectin-3 (Gal-3) is an animal lectin involved in both innate and adaptive immune responses. The present study aimed to evaluate the influence of Gal-3 on [...] Read more.
Cryptococcus neoformans, the causative agent of cryptococcosis, is the primary fungal pathogen that affects the immunocompromised individuals. Galectin-3 (Gal-3) is an animal lectin involved in both innate and adaptive immune responses. The present study aimed to evaluate the influence of Gal-3 on the C. neoformans infection. We performed histopathological and gene profile analysis of the innate antifungal immunity markers in the lungs, spleen, and brain of the wild-type (WT) and Gal-3 knockout (KO) mice during cryptococcosis. These findings suggest that Gal-3 absence does not cause significant histopathological alterations in the analyzed tissues. The expression profile of the genes related to innate antifungal immunity showed that the presence of cryptococcosis in the WT and Gal-3 KO animals, compared to their respective controls, promoted the upregulation of the pattern recognition receptor (PRR) responsive to mannose/chitin (mrc1) and a gene involved in inflammation (ccr5), as well as the downregulation of the genes related to signal transduction (card9, fos, ikbkb, jun) and PRRs (cd209a, colec12, nptx1). The absence of Gal-3, in fungal infection, a positively modulated gene involved in phagocytosis (sftpd) and negatively genes involved in signal transduction (syk and myd88), proinflammatory cytokines il-1β and il-12b and cd209a receptor. Therefore, our results suggest that Gal-3 may play an essential role in the development of antifungal immune responses against cryptococcosis. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
►▼ Show Figures

Figure 1

24 pages, 1894 KiB  
Article
What Are the Best Parents for Hybrid Progeny? An Investigation into the Human Pathogenic Fungus Cryptococcus
by Man You and Jianping Xu
J. Fungi 2021, 7(4), 299; https://doi.org/10.3390/jof7040299 - 15 Apr 2021
Cited by 5 | Viewed by 2403
Abstract
Hybridization between more divergent organisms is likely to generate progeny with more novel genetic interactions and genetic variations. However, the relationship between parental genetic divergence and progeny phenotypic variation remains largely unknown. Here, using strains of the human pathogenic Cryptococcus, we investigated [...] Read more.
Hybridization between more divergent organisms is likely to generate progeny with more novel genetic interactions and genetic variations. However, the relationship between parental genetic divergence and progeny phenotypic variation remains largely unknown. Here, using strains of the human pathogenic Cryptococcus, we investigated the patterns of such a relationship. Twenty-two strains with up to 15% sequence divergence were mated. Progeny were genotyped at 16 loci. Parental strains and their progeny were phenotyped for growth ability at two temperatures, melanin production at seven conditions, and susceptibility to the antifungal drug fluconazole. We observed three patterns of relationships between parents and progeny for each phenotypic trait, including (i) similar to one of the parents, (ii) intermediate between the parents, and (iii) outside the parental phenotypic range. We found that as genetic distance increases between parental strains, progeny showed increased fluconazole resistance and growth at 37 °C but decreased melanin production under various oxidative and nitrosative stresses. Our findings demonstrate that, depending on the traits, both evolutionarily more similar strains and more divergent strains may be better parents to generate progeny with hybrid vigor. Together, the results indicate the enormous potential of Cryptococcus hybrids in their evolution and adaptation to diverse conditions. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
►▼ Show Figures

Figure 1

Review

Jump to: Research

14 pages, 593 KiB  
Review
Methods for Manipulating Cryptococcus Spores
by Anna B. Frerichs, Mingwei Huang, Sébastien C. Ortiz and Christina M. Hull
J. Fungi 2022, 8(1), 4; https://doi.org/10.3390/jof8010004 - 22 Dec 2021
Cited by 6 | Viewed by 7541
Abstract
Spores are essential for the long-term survival of many diverse organisms, due to their roles in reproduction and stress resistance. In the environmental human fungal pathogen, Cryptococcus, basidiospores are robust cells with the ability to cause disease in animal models of infection. [...] Read more.
Spores are essential for the long-term survival of many diverse organisms, due to their roles in reproduction and stress resistance. In the environmental human fungal pathogen, Cryptococcus, basidiospores are robust cells with the ability to cause disease in animal models of infection. Here we describe methods for producing and purifying Cryptococcus basidiospores in quantities sufficient for large-scale analyses. The production of high numbers of pure spores has facilitated the development of new assays, including quantitative germination assays, and enabled transcriptomic, proteomic, and virulence studies, leading to discoveries of behaviors and properties unique to spores and spore-mediated disease. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
►▼ Show Figures

Figure 1

14 pages, 1443 KiB  
Review
Optimizing Transformation Frequency of Cryptococcus neoformans and Cryptococcus gattii Using Agrobacterium tumefaciens
by Jianmin Fu, Nohelli E. Brockman and Brian L. Wickes
J. Fungi 2021, 7(7), 520; https://doi.org/10.3390/jof7070520 - 29 Jun 2021
Cited by 2 | Viewed by 2337
Abstract
The transformation of Cryptococcus spp. by Agrobacterium tumefaciens has proven to be a useful genetic tool. A number of factors affect transformation frequency. These factors include acetosyringone concentration, bacterial cell to yeast cell ratio, cell wall damage, and agar concentration. Agar concentration was [...] Read more.
The transformation of Cryptococcus spp. by Agrobacterium tumefaciens has proven to be a useful genetic tool. A number of factors affect transformation frequency. These factors include acetosyringone concentration, bacterial cell to yeast cell ratio, cell wall damage, and agar concentration. Agar concentration was found to have a significant effect on the transformant number as transformants increased with agar concentration across all four serotypes. When infection time points were tested, higher agar concentrations were found to result in an earlier transfer of the Ti-plasmid to the yeast cell, with the earliest transformant appearing two h after A. tumefaciens contact with yeast cells. These results demonstrate that A. tumefaciens transformation efficiency can be affected by a variety of factors and continued investigation of these factors can lead to improvements in specific A. tumefaciens/fungus transformation systems. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
►▼ Show Figures

Figure 1

21 pages, 1608 KiB  
Review
Cryptococcus neoformans and Cryptococcus gattii Species Complexes in Latin America: A Map of Molecular Types, Genotypic Diversity, and Antifungal Susceptibility as Reported by the Latin American Cryptococcal Study Group
by Carolina Firacative, Wieland Meyer and Elizabeth Castañeda
J. Fungi 2021, 7(4), 282; https://doi.org/10.3390/jof7040282 - 9 Apr 2021
Cited by 27 | Viewed by 5246
Abstract
Cryptococcosis, a potentially fatal mycosis, is caused by members of the Cryptococcus neoformans and Cryptococcus gattii species complexes. In Latin America, cryptococcal meningitis is still an important health threat with a significant clinical burden. Analysis of publicly available molecular data from 5686 clinical, [...] Read more.
Cryptococcosis, a potentially fatal mycosis, is caused by members of the Cryptococcus neoformans and Cryptococcus gattii species complexes. In Latin America, cryptococcal meningitis is still an important health threat with a significant clinical burden. Analysis of publicly available molecular data from 5686 clinical, environmental, and veterinary cryptococcal isolates from member countries of the Latin American Cryptococcal Study Group showed that, as worldwide, C. neoformans molecular type VNI is the most common cause of cryptococcosis (76.01%) in HIV-infected people, followed by C. gattii molecular type VGII (12.37%), affecting mostly otherwise healthy hosts. These two molecular types also predominate in the environment (68.60% for VNI and 20.70% for VGII). Among the scarce number of veterinary cases, VGII is the predominant molecular type (73.68%). Multilocus sequence typing analysis showed that, in Latin America, the C. neoformans population is less diverse than the C. gattii population (D of 0.7104 vs. 0.9755). Analysis of antifungal susceptibility data showed the presence of non-wild-type VNI, VGI, VGII, and VGIII isolates in the region. Overall, the data presented herein summarize the progress that has been made towards the molecular epidemiology of cryptococcal isolates in Latin America, contributing to the characterization of the genetic diversity and antifungal susceptibility of these globally spreading pathogenic yeasts. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
►▼ Show Figures

Figure 1

14 pages, 2555 KiB  
Review
Tools for Assessing Translation in Cryptococcus neoformans
by Corey M. Knowles, Kelcy M. McIntyre and John C. Panepinto
J. Fungi 2021, 7(3), 159; https://doi.org/10.3390/jof7030159 - 24 Feb 2021
Cited by 5 | Viewed by 3028
Abstract
Cryptococcus neoformans is a ubiquitous environmental fungus capable of establishing an infection in a human host. Rapid changes in environments and exposure to the host immune system results in a significant amount of cellular stress, which is effectively combated at the level of [...] Read more.
Cryptococcus neoformans is a ubiquitous environmental fungus capable of establishing an infection in a human host. Rapid changes in environments and exposure to the host immune system results in a significant amount of cellular stress, which is effectively combated at the level of translatome reprogramming. Repression of translation following stress allows for the specific reallocation of limited resources. Understanding the mechanisms involved in regulating translation in C. neoformans during host infection is critical in the development of new antifungal drugs. In this review, we discuss the main tools available for assessing changes in translation state and translational output during cellular stress. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
►▼ Show Figures

Figure 1

10 pages, 264 KiB  
Review
Genetic Transformation in Cryptococcus Species
by Ping Wang
J. Fungi 2021, 7(1), 56; https://doi.org/10.3390/jof7010056 - 15 Jan 2021
Cited by 7 | Viewed by 3490
Abstract
Genetic transformation plays an imperative role in our understanding of the biology in unicellular yeasts and filamentous fungi, such as Saccharomyces cerevisiae, Aspergillus nidulans, Cryphonectria parasitica, and Magnaporthe oryzae. It also helps to understand the virulence and drug resistance mechanisms of [...] Read more.
Genetic transformation plays an imperative role in our understanding of the biology in unicellular yeasts and filamentous fungi, such as Saccharomyces cerevisiae, Aspergillus nidulans, Cryphonectria parasitica, and Magnaporthe oryzae. It also helps to understand the virulence and drug resistance mechanisms of the pathogenic fungus Cryptococcus that causes cryptococcosis in health and immunocompromised individuals. Since the first attempt at DNA transformation in this fungus by Edman in 1992, various methods and techniques have been developed to introduce DNA into this organism and improve the efficiency of homology-mediated gene disruption. There have been many excellent summaries or reviews covering the subject. Here we highlight some of the significant achievements and additional refinements in the genetic transformation of Cryptococcus species. Full article
(This article belongs to the Special Issue Molecular and Genetic Tools for Studying Cryptococcus spp.)
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-8
Back to TopTop