TY - JOUR
T1 - The DEAD-box RNA helicase Vad1 regulates multiple virulence-associated genes in Cryptococcus neoformans
AU - Panepinto, John
AU - Liu, Lide
AU - Ramos, Jeanie
AU - Zhu, Xudong
AU - Valyi-Nagy, Tibor
AU - Eksi, Saliha
AU - Fu, Jianmin
AU - Jaffe, H. Ari
AU - Wickes, Brian
AU - Williamson, Peter R.
PY - 2005/3
Y1 - 2005/3
N2 - The study of fungal regulatory networks is essential to the understanding of how these pathogens respond to host environmental signals with effective virulence-associated traits. In this study, a virulence-associated DEAD-box RNA helicase-encoding gene (VAD1) was isolated from a mutant defective in the virulence factor laccase. A Δvad1 mutant exhibited a profound reduction in virulence in a mouse model that was restored after reconstitution with WT VAD1. Loss of VAD1 resulted in upregulation of NOT1, a gene encoding a global repressor of transcription. NOT1 was found to act as an intermediary transcriptional repressor of laccase. Vad1 was located within macromolecular complexes that formed cytoplasmic granular bodies in mature cells and during infection of mouse brain. In addition, VAD1 was shown by in situ hybridization to be expressed in the brain of an AIDS patient coinfected with C. neoformans. To understand the role of VAD1 in virulence, a functional genomics approach was used to identify 3 additional virulence determinants dependent on VAD1: PCK1, TUF1, and MPF3, involved in gluconeogenesis, mitochondrial protein synthesis, and cell wall integrity, respectively. These data show that fungal virulence-associated genes are coordinately regulated and that an analysis of such transcriptomes allows for the identification of important new genes involved in the normal growth and virulence of fungal pathogens.
AB - The study of fungal regulatory networks is essential to the understanding of how these pathogens respond to host environmental signals with effective virulence-associated traits. In this study, a virulence-associated DEAD-box RNA helicase-encoding gene (VAD1) was isolated from a mutant defective in the virulence factor laccase. A Δvad1 mutant exhibited a profound reduction in virulence in a mouse model that was restored after reconstitution with WT VAD1. Loss of VAD1 resulted in upregulation of NOT1, a gene encoding a global repressor of transcription. NOT1 was found to act as an intermediary transcriptional repressor of laccase. Vad1 was located within macromolecular complexes that formed cytoplasmic granular bodies in mature cells and during infection of mouse brain. In addition, VAD1 was shown by in situ hybridization to be expressed in the brain of an AIDS patient coinfected with C. neoformans. To understand the role of VAD1 in virulence, a functional genomics approach was used to identify 3 additional virulence determinants dependent on VAD1: PCK1, TUF1, and MPF3, involved in gluconeogenesis, mitochondrial protein synthesis, and cell wall integrity, respectively. These data show that fungal virulence-associated genes are coordinately regulated and that an analysis of such transcriptomes allows for the identification of important new genes involved in the normal growth and virulence of fungal pathogens.
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U2 - 10.1172/JCI200523048
DO - 10.1172/JCI200523048
M3 - Article
C2 - 15765146
AN - SCOPUS:20044375362
SN - 0021-9738
VL - 115
SP - 632
EP - 641
JO - Journal of Clinical Investigation
JF - Journal of Clinical Investigation
IS - 3
ER -