Unraveling the Pathobiological Role of the Fungal KEOPS Complex in Cryptococcus neoformans

Choi, Yeseul; Jeong, Eun-Ji; Lee, Dong-Gi; Jin, Jae-Hyung; So, Yee-Seul; Yu, Seong-Ryong; Ha, Hye-Jeong; Lin, Chih-Wei; Chen, Ying-Lien; Park, Jun Bae; Cho, Hyun-Soo; Averette, Anna Floyd; Heitman, Joseph; Lee, Kyung-Jo; Lee, Kangseok; Bahn, Yong-Sun

doi:10.1128/mbio.02944-22

Cited by 5 publications

(14 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1D ), mirroring that of its S. cerevisiae counterpart, which is known to localize in the cytoplasm, nucleus, and mitochondria ( 15 ). This uniform distribution is also consistent with earlier observations regarding the C. neoformans KEOPS complex ( 14 ). Importantly, reintroducing the SUA5-mRuby3 allele into the sua5 Δ mutant successfully restored the wild-type primer extension pattern at position 39 of the Ile tRNA ( Fig.…”

Section: Resultssupporting

confidence: 92%

“…We then examined whether Sua5 plays an expected role in t 6 A tRNA modification via its involvement in TC-AMP biosynthesis. Building upon our previous work, which highlighted the role of the KEOPS complex in t 6 A tRNA modification ( 14 ), we conducted a primer extension analysis using t 6 A-containing tRNA (Ile AAU) extracted from wild-type, bud32 Δ, and sua5 Δ strains. The primer extension profiles revealed that the sua5 Δ mutant closely resembled the bud32 Δ but markedly diverged from the wild-type strain at nucleotide position 39, corresponding to position 37 in the S. cerevisiae tRNA (Ile AAU) ( Fig.…”

Section: Resultsmentioning

confidence: 99%

“…Recently, we conducted an in-depth analysis of the various biological roles of the KEOPS complex in Cryptococcus neoformans (Cn), a fungal pathogen notorious for causing meningoencephalitis worldwide ( 14 ). Structurally, the CnKEOPS complex is linearly organized as Pcc1-Kae1-Bud32-Cgi121 but notably lacks a Gon7-like ortholog found in S. cerevisiae .…”

Section: Introductionmentioning

confidence: 99%

“…Structurally, the CnKEOPS complex is linearly organized as Pcc1-Kae1-Bud32-Cgi121 but notably lacks a Gon7-like ortholog found in S. cerevisiae . When any component of the CnKEOPS complex is deleted, we observed significant abnormalities in multiple aspects of the fungal biology, including vegetative growth, cell cycle control, sexual differentiation, production of protective structures like capsule and melanin, as well as in t 6 A tRNA modification ( 14 ). Furthermore, the CnKEOPS complex acts as a significant transcriptional regulator, influencing hundreds of genes related to carbon and nitrogen metabolism, sterol biosynthesis, mating, and other vital cellular functions.…”

Section: Introductionmentioning

confidence: 99%

“…Furthermore, the CnKEOPS complex acts as a significant transcriptional regulator, influencing hundreds of genes related to carbon and nitrogen metabolism, sterol biosynthesis, mating, and other vital cellular functions. Given its wide-ranging impacts, the absence of any KEOPS component significantly diminishes the virulence of C. neoformans ( 14 ). However, it remains an open question whether the diverse functionalities of the CnKEOPS complex stem from its role in tRNA modification or other cellular activities.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Sua5 catalyzing universal t ⁶ A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans

Choi,

Hyeon,

Lee

et al. 2024

mSphere

Self Cite

View full text Add to dashboard Cite

The N 6 -threonylcarbamoyl adenosine (t 6 A) tRNA modification is critical for ensuring translation fidelity across three domains of life. Our prior work highlighted the KEOPS complex, organized in a Pcc1-Kae1-Bud32-Cgi121 linear arrangement, not only serves an evolutionarily conserved role in t 6 A tRNA modification but also exerts diverse functional impacts on pathobiological characteristics in Cryptococcus neoformans , a leading cause of fungal meningitis worldwide. However, the extent to which the pleiotropic functions of the KEOPS complex are specifically tied to tRNA modification remains uncertain. To address this, we undertook a functional characterization of Sua5, responsible for generating the precursor threonylcarbamoyl-adenylate (TC-AMP) for t 6 A tRNA modification, using a reverse genetics approach. Comparative phenotypic analyses with KEOPS mutants revealed that Sua5 plays a vital role in multiple cellular processes, such as t 6 A tRNA modification, growth, sexual development, stress response, and virulence factor production, thus reflecting the multifaceted functions of the KEOPS complex. In support of this, sua5 Δ bud32 Δ double mutants showed phenotypes comparable to those of the corresponding single mutants. Intriguingly, a SUA5 allele lacking a mitochondria targeting sequence ( SUA5 MTS Δ ) was sufficient to restore the wild-type phenotypes in the sua5 Δ mutant, suggesting that Sua5’s primary functional locus may be cytosolic, akin to the KEOPS complex. Further supporting this, the deletion of Qri7, a mitochondrial paralog of Kae1, had no discernible phenotypic impact on C. neoformans . We concluded that cytosolic t 6 A tRNA modifications, orchestrated by Sua5 and the KEOPS complex, are central to the regulation of diverse pathobiological functions in C. neoformans . IMPORTANCE Understanding cellular functions at the molecular level is crucial for advancing disease treatments. Our research reveals a critical connection between the KEOPS complex and Sua5 in Cryptococcus neoformans , a significant cause of fungal meningitis. While the KEOPS complex is known for its versatile roles in cellular processes, Sua5 is specialized in t 6 A tRNA modification. Our key finding is that the diverse roles of the KEOPS complex, ranging from cell growth and stress response to virulence, are fundamentally linked to its function in t 6 A tRNA modification. This conclusion is supported by the remarkable similarities between the impacts of Sua5 and KEOPS on these processes, despite their roles in different steps of the t 6 A modification pathway. This newfound understanding deepens our insight into fungal biology and opens new avenues for developing potential therapies against dangerous fungal diseases.

show abstract

Section: Resultssupporting

confidence: 92%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Sua5 catalyzing universal t ⁶ A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans

Choi,

Hyeon,

Lee

et al. 2024

mSphere

Self Cite

View full text Add to dashboard Cite

show abstract

Molecular basis of A. thaliana KEOPS complex in biosynthesizing tRNA t6A

Zheng,

Su,

Duan

et al. 2024

Nucleic Acids Research

View full text Add to dashboard Cite

In archaea and eukaryotes, the evolutionarily conserved KEOPS is composed of four core subunits―Kae1, Bud32, Cgi121 and Pcc1, and a fifth Gon7/Pcc2 that is found in fungi and metazoa. KEOPS cooperates with Sua5/YRDC to catalyze the biosynthesis of tRNA N6-threonylcarbamoyladenosine (t6A), an essential modification needed for fitness of cellular organisms. Biochemical and structural characterizations of KEOPSs from archaea, yeast and humans have determined a t6A-catalytic role for Kae1 and auxiliary roles for other subunits. However, the precise molecular workings of KEOPSs still remain poorly understood. Here, we investigated the biochemical functions of A. thaliana KEOPS and determined a cryo-EM structure of A. thaliana KEOPS dimer. We show that A. thaliana KEOPS is composed of KAE1, BUD32, CGI121 and PCC1, which adopts a conserved overall arrangement. PCC1 dimerization leads to a KEOPS dimer that is needed for an active t6A-catalytic KEOPS–tRNA assembly. BUD32 participates in direct binding of tRNA to KEOPS and modulates the t6A-catalytic activity of KEOPS via its C-terminal tail and ATP to ADP hydrolysis. CGI121 promotes the binding of tRNA to KEOPS and potentiates the t6A-catalytic activity of KEOPS. These data and findings provide insights into mechanistic understanding of KEOPS machineries.

show abstract

tRNA hypomodification facilitates 5-fluorocytosine resistance via cross-pathway control system activation inAspergillus fumigatus

Bruch,

Lazarova,

Berg

et al. 2024

Preprint

View full text Add to dashboard Cite

Increasing antifungal drug resistance is a major concern associated with human fungal infections. Genetic mutation and epimutation mechanisms are clear drivers of resistance, yet the epitranscriptome remains relatively untested regarding resistance. Here, deletion of theAspergillus fumigatustRNA-modifying isopentenyl transferase ortholog, Mod5, led to altered stress response and unexpected resistance against the antifungal drug 5-fluorocytosine (5-FC). Simultaneous profiling of transcriptomes and proteomes revealed comparable general adaptation to 5-FC stress; however, a premature activation of cross-pathway control (CPC) genes in the knockout was further increased after antifungal treatment. By associating codon usage patterns with proteomics abundances, we observed a negative correlation with the number of tRNATyrGΨA-decoded codons in the knockout, indicative of modification-tuneable transcripts. Subsequent overexpression of tRNATyrGΨAin the ∆mod5strain rescued select phenotypes but failed to reverse 5-FC resistance. Investigation of the purported tRNA gene-mediated silencing function of Mod5 uncovered a negative correlation between tRNA proximity and gene induction under normal growth, indicating an active pathway. In conclusion, 5-FC resistance in the absence of Mod5 likely originates from multifaceted transcriptional and translational changes that skew the fungus towards starvation responses over optimal growth, offering a mechanism reliant on RNA modification and tRNA gene-mediated silencing to facilitate transient antifungal resistance.

show abstract

Unraveling the Pathobiological Role of the Fungal KEOPS Complex in Cryptococcus neoformans

Cited by 5 publications

References 44 publications

Sua5 catalyzing universal t ⁶ A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans

Sua5 catalyzing universal t ⁶ A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans

Molecular basis of A. thaliana KEOPS complex in biosynthesizing tRNA t6A

tRNA hypomodification facilitates 5-fluorocytosine resistance via cross-pathway control system activation inAspergillus fumigatus

Contact Info

Product

Resources

About

Unraveling the Pathobiological Role of the Fungal KEOPS Complex in Cryptococcus neoformans

Cited by 5 publications

References 44 publications

Sua5 catalyzing universal t 6 A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans

Sua5 catalyzing universal t 6 A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans

Molecular basis of A. thaliana KEOPS complex in biosynthesizing tRNA t6A

tRNA hypomodification facilitates 5-fluorocytosine resistance via cross-pathway control system activation inAspergillus fumigatus

Contact Info

Product

Resources

About

Sua5 catalyzing universal t ⁶ A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans

Sua5 catalyzing universal t ⁶ A tRNA modification is responsible for multifaceted functions of the KEOPS complex in Cryptococcus neoformans