Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.

Calcineurin is a highly conserved Ca2+/calmodulin-dependent serine/threonine-specific protein phosphatase that orchestrates cellular Ca2+ signaling responses. In Cryptococcus neoformans, calcineurin is activated by multiple stresses including high temperature, and is essential for stress adaptation...

Full description

Bibliographic Details
Main Authors: Eve W L Chow, Shelly A Clancey, R Blake Billmyre, Anna Floyd Averette, Joshua A Granek, Piotr Mieczkowski, Maria E Cardenas, Joseph Heitman
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-04-01
Series:PLoS Genetics
Online Access:http://europepmc.org/articles/PMC5380312?pdf=render
_version_ 1819211443352895488
author Eve W L Chow
Shelly A Clancey
R Blake Billmyre
Anna Floyd Averette
Joshua A Granek
Piotr Mieczkowski
Maria E Cardenas
Joseph Heitman
author_facet Eve W L Chow
Shelly A Clancey
R Blake Billmyre
Anna Floyd Averette
Joshua A Granek
Piotr Mieczkowski
Maria E Cardenas
Joseph Heitman
author_sort Eve W L Chow
collection DOAJ
description Calcineurin is a highly conserved Ca2+/calmodulin-dependent serine/threonine-specific protein phosphatase that orchestrates cellular Ca2+ signaling responses. In Cryptococcus neoformans, calcineurin is activated by multiple stresses including high temperature, and is essential for stress adaptation and virulence. The transcription factor Crz1 is a major calcineurin effector in Saccharomyces cerevisiae and other fungi. Calcineurin dephosphorylates Crz1, thereby enabling Crz1 nuclear translocation and transcription of target genes. Here we show that loss of Crz1 confers phenotypes intermediate between wild-type and calcineurin mutants, and demonstrate that deletion of the calcineurin docking domain results in the inability of Crz1 to translocate into the nucleus under thermal stress. RNA-sequencing revealed 102 genes that are regulated in a calcineurin-Crz1-dependent manner at 37°C. The majority of genes were down-regulated in cna1Δ and crz1Δ mutants, indicating these genes are normally activated by the calcineurin-Crz1 pathway at high temperature. About 58% of calcineurin-Crz1 target genes have unknown functions, while genes with known or predicted functions are involved in cell wall remodeling, calcium transport, and pheromone production. We identified three calcineurin-dependent response element motifs within the promoter regions of calcineurin-Crz1 target genes, and show that Crz1 binding to target gene promoters is increased upon thermal stress in a calcineurin-dependent fashion. Additionally, we found a large set of genes independently regulated by calcineurin, and Crz1 regulates 59 genes independently of calcineurin. Given the intermediate crz1Δ mutant phenotype, and our recent evidence for a calcineurin regulatory network impacting mRNA in P-bodies and stress granules independently of Crz1, calcineurin likely acts on factors beyond Crz1 that govern mRNA expression/stability to operate a branched transcriptional/post-transcriptional stress response network necessary for fungal virulence. Taken together, our findings reveal the core calcineurin-Crz1 stress response cascade is maintained from ascomycetes to a pathogenic basidiomycete fungus, but its output in C. neoformans appears to be adapted to promote fungal virulence.
first_indexed 2024-12-23T06:27:09Z
format Article
id doaj.art-dfe7e5afecf14621a9f0266cad3d30f9
institution Directory Open Access Journal
issn 1553-7390
1553-7404
language English
last_indexed 2024-12-23T06:27:09Z
publishDate 2017-04-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Genetics
spelling doaj.art-dfe7e5afecf14621a9f0266cad3d30f92022-12-21T17:57:02ZengPublic Library of Science (PLoS)PLoS Genetics1553-73901553-74042017-04-01134e100666710.1371/journal.pgen.1006667Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.Eve W L ChowShelly A ClanceyR Blake BillmyreAnna Floyd AveretteJoshua A GranekPiotr MieczkowskiMaria E CardenasJoseph HeitmanCalcineurin is a highly conserved Ca2+/calmodulin-dependent serine/threonine-specific protein phosphatase that orchestrates cellular Ca2+ signaling responses. In Cryptococcus neoformans, calcineurin is activated by multiple stresses including high temperature, and is essential for stress adaptation and virulence. The transcription factor Crz1 is a major calcineurin effector in Saccharomyces cerevisiae and other fungi. Calcineurin dephosphorylates Crz1, thereby enabling Crz1 nuclear translocation and transcription of target genes. Here we show that loss of Crz1 confers phenotypes intermediate between wild-type and calcineurin mutants, and demonstrate that deletion of the calcineurin docking domain results in the inability of Crz1 to translocate into the nucleus under thermal stress. RNA-sequencing revealed 102 genes that are regulated in a calcineurin-Crz1-dependent manner at 37°C. The majority of genes were down-regulated in cna1Δ and crz1Δ mutants, indicating these genes are normally activated by the calcineurin-Crz1 pathway at high temperature. About 58% of calcineurin-Crz1 target genes have unknown functions, while genes with known or predicted functions are involved in cell wall remodeling, calcium transport, and pheromone production. We identified three calcineurin-dependent response element motifs within the promoter regions of calcineurin-Crz1 target genes, and show that Crz1 binding to target gene promoters is increased upon thermal stress in a calcineurin-dependent fashion. Additionally, we found a large set of genes independently regulated by calcineurin, and Crz1 regulates 59 genes independently of calcineurin. Given the intermediate crz1Δ mutant phenotype, and our recent evidence for a calcineurin regulatory network impacting mRNA in P-bodies and stress granules independently of Crz1, calcineurin likely acts on factors beyond Crz1 that govern mRNA expression/stability to operate a branched transcriptional/post-transcriptional stress response network necessary for fungal virulence. Taken together, our findings reveal the core calcineurin-Crz1 stress response cascade is maintained from ascomycetes to a pathogenic basidiomycete fungus, but its output in C. neoformans appears to be adapted to promote fungal virulence.http://europepmc.org/articles/PMC5380312?pdf=render
spellingShingle Eve W L Chow
Shelly A Clancey
R Blake Billmyre
Anna Floyd Averette
Joshua A Granek
Piotr Mieczkowski
Maria E Cardenas
Joseph Heitman
Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.
PLoS Genetics
title Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.
title_full Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.
title_fullStr Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.
title_full_unstemmed Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.
title_short Elucidation of the calcineurin-Crz1 stress response transcriptional network in the human fungal pathogen Cryptococcus neoformans.
title_sort elucidation of the calcineurin crz1 stress response transcriptional network in the human fungal pathogen cryptococcus neoformans
url http://europepmc.org/articles/PMC5380312?pdf=render
work_keys_str_mv AT evewlchow elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans
AT shellyaclancey elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans
AT rblakebillmyre elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans
AT annafloydaverette elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans
AT joshuaagranek elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans
AT piotrmieczkowski elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans
AT mariaecardenas elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans
AT josephheitman elucidationofthecalcineurincrz1stressresponsetranscriptionalnetworkinthehumanfungalpathogencryptococcusneoformans