Genetic basis for coordination of meiosis and sexual structure maturation in Cryptococcus neoformans
- Institute of Microbiology, Chinese Academy of Sciences, China
- Southwest University, China
- School of Basic Medical Sciences, Peking University Health Science Center, China
Abstract
In the human fungal pathogen Cryptococcus neoformans, sex can benefit its pathogenicity through production of meiospores, which are believed to offer both physical and meiosis-created lineage advantages for its infections. Cryptococcus sporulation occurs following two parallel events, meiosis and differentiation of the basidium, the characteristic sexual structure of the basidiomycetes. However, the circuit integrating these events to ensure subsequent sporulation is unclear. Here, we show the spatiotemporal coordination of meiosis and basidial maturation by visualizing event-specific molecules in developing basidia defined by a quantitative approach. Monitoring of gene induction timing together with genetic analysis reveals co-regulation of the coordinated events by a shared regulatory program. Two RRM family regulators, Csa1 and Csa2, are crucial components that specifically bridge meiosis and basidial maturation, further determining sporulation. We propose that the regulatory coordination of meiosis and basidial development serves as a determinant underlying the production of infectious meiospores in C. neoformans.
Data availability
The GEO accession number for the RNA-seq data reported in this study is GSE111975.
Article and author information
Author details
Funding
Ministry of Science and Technology of the People's Republic of China (2018ZX10101004)
- Linqi Wang
National Natural Science Foundation of China (31622004,31570138,31770163)
- Linqi Wang
Chinese Academy of Sciences Key Project (QYZDB-SSW-SSMC040)
- Linqi Wang
National Natural Science Foundation of China (31501008)
- Guang-Jun He
National Natural Science Foundation of China (31501009)
- Xiuyun Tian
The funders had roles in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Liu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Genetic basis for coordination of meiosis and sexual structure maturation in Cryptococcus neoformans
eLife 7:e38683.
https://doi.org/10.7554/eLife.38683
Further reading
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Background:
Under which conditions antibiotic combination therapy decelerates rather than accelerates resistance evolution is not well understood. We examined the effect of combining antibiotics on within-patient resistance development across various bacterial pathogens and antibiotics.
Methods:
We searched CENTRAL, EMBASE, and PubMed for (quasi)-randomised controlled trials (RCTs) published from database inception to 24 November 2022. Trials comparing antibiotic treatments with different numbers of antibiotics were included. Patients were considered to have acquired resistance if, at the follow-up culture, a resistant bacterium (as defined by the study authors) was detected that had not been present in the baseline culture. We combined results using a random effects model and performed meta-regression and stratified analyses. The trials’ risk of bias was assessed with the Cochrane tool.
Results:
42 trials were eligible and 29, including 5054 patients, qualified for statistical analysis. In most trials, resistance development was not the primary outcome and studies lacked power. The combined odds ratio for the acquisition of resistance comparing the group with the higher number of antibiotics with the comparison group was 1.23 (95% CI 0.68–2.25), with substantial between-study heterogeneity (I2=77%). We identified tentative evidence for potential beneficial or detrimental effects of antibiotic combination therapy for specific pathogens or medical conditions.
Conclusions:
The evidence for combining a higher number of antibiotics compared to fewer from RCTs is scarce and overall compatible with both benefit or harm. Trials powered to detect differences in resistance development or well-designed observational studies are required to clarify the impact of combination therapy on resistance.
Funding:
Support from the Swiss National Science Foundation (grant 310030B_176401 (SB, BS, CW), grant 32FP30-174281 (ME), grant 324730_207957 (RDK)) and from the National Institute of Allergy and Infectious Diseases (NIAID, cooperative agreement AI069924 (ME)) is gratefully acknowledged.
