The Region in a Subunit of the<i>Aspergillus</i>CCAAT-Binding Protein Similar to the HAP4p-Recruiting Domain of<i>Saccharomyces cerevisiae</i>Hap5p Is Not Essential for Transcriptional Enhancement

Tanoue, Shinjiro; Kamei, Kaeko; Goda, Hideya; Tanaka, Akimitsu; Kobayashi, Tetsuo; Tsukagoshi, Norihiro; Kato, Masashi

doi:10.1271/bbb.70.782

Cited by 4 publications

(3 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast, domain A is only conserved among fungal HapE orthologs and has been shown to be required for the recruitment of Hap4p in S. cerevisiae . Recently, Tanoue et al (2006) reported that only the B‐domain is required for CBC‐mediated transcriptional activation in A. nidulans . Here, we found that deletion of the non‐conserved N‐terminal region and the A‐domain phenocopies hapX deletion, that is, wild type‐like growth during +Fe conditions, but decreased growth rate, reduced TAFC production, and increased accumulation of FC and PpIX during −Fe conditions (Figure 4B).…”

Section: Resultsmentioning

confidence: 99%

“…( B ) Growth rates and production of TAFC, FC and PpIX after growth for 48 h during+Fe and −Fe conditions. For induction of amylase promoter‐driven genes (Tanoue et al , 2006), strains were grown in medium containing starch as the sole carbon source. During +Fe conditions, production of TAFC, FC and PpIX was wild type‐like in all strains (data not shown).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Interaction of HapX with the CCAAT-binding complex—a novel mechanism of gene regulation by iron

Hortschansky

Eisendle

Abdallah

et al. 2007

EMBO J

Self Cite

209

316

View full text Add to dashboard Cite

Iron homeostasis requires subtle control systems, as iron is both essential and toxic. In Aspergillus nidulans, iron represses iron acquisition via the GATA factor SreA, and induces iron-dependent pathways at the transcriptional level, by a so far unknown mechanism. Here, we demonstrate that iron-dependent pathways (e.g., heme biosynthesis) are repressed during iron-depleted conditions by physical interaction of HapX with the CCAAT-binding core complex (CBC). Proteome analysis identified putative HapX targets. Mutual transcriptional control between hapX and sreA and synthetic lethality resulting from deletion of both regulatory genes indicate a tight interplay of these control systems. Expression of genes encoding CBC subunits was not influenced by iron availability, and their deletion was deleterious during iron-depleted and iron-replete conditions. Expression of hapX was repressed by iron and its deletion was deleterious during irondepleted conditions only. These data indicate that the CBC has a general role and that HapX function is confined to iron-depleted conditions. Remarkably, CBC-mediated regulation has an inverse impact on the expression of the same gene set in A. nidulans, compared with Saccharomyces cerevisae.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Interaction of HapX with the CCAAT-binding complex—a novel mechanism of gene regulation by iron

Hortschansky

Eisendle

Abdallah

et al. 2007

EMBO J

Self Cite

209

316

View full text Add to dashboard Cite

show abstract

“…The complex is a transcription factor that specifically recognizes the regulatory CCAAT element found in the forward or reverse orientation in promoter regions of numerous eukaryotic genes [70]. The hapE gene contains four exons and the mutation is situated in the fourth exon, in the evolutionary conserved core domain [62], [63], [71], suggesting that P88 is an important amino acid for the function of the protein. Moreover, in the human NF-YC (the mammalian HapE homologue) deletion of residues 43–45 (homologous to A. fumigatus residues 87–89), are deleterious for DNA binding [72], indicating that P88 is needed for the Hap-complex to bind the regulatory CCAAT element and initiate transcription.…”

Section: Discussionmentioning

confidence: 99%

Discovery of a hapE Mutation That Causes Azole Resistance in Aspergillus fumigatus through Whole Genome Sequencing and Sexual Crossing

et al. 2012

View full text Add to dashboard Cite

Azole compounds are the primary therapy for patients with diseases caused by Aspergillus fumigatus. However, prolonged treatment may cause resistance to develop, which is associated with treatment failure. The azole target cyp51A is a hotspot for mutations that confer phenotypic resistance, but in an increasing number of resistant isolates the underlying mechanism remains unknown. Here, we report the discovery of a novel resistance mechanism, caused by a mutation in the CCAAT-binding transcription factor complex subunit HapE. From one patient, four A. fumigatus isolates were serially collected. The last two isolates developed an azole resistant phenotype during prolonged azole therapy. Because the resistant isolates contained a wild type cyp51A gene and the isolates were isogenic, the complete genomes of the last susceptible isolate and the first resistant isolate (taken 17 weeks apart) were sequenced using Illumina technology to identify the resistance conferring mutation. By comparing the genome sequences to each other as well as to two A. fumigatus reference genomes, several potential non-synonymous mutations in protein-coding regions were identified, six of which could be confirmed by PCR and Sanger sequencing. Subsequent sexual crossing experiments showed that resistant progeny always contained a P88L substitution in HapE, while the presence of the other five mutations did not correlate with resistance in the progeny. Cloning the mutated hapE gene into the azole susceptible akuB KU80 strain showed that the HapE P88L mutation by itself could confer the resistant phenotype. This is the first time that whole genome sequencing and sexual crossing strategies have been used to find the genetic basis of a trait of interest in A. fumigatus. The discovery may help understand alternate pathways for azole resistance in A. fumigatus with implications for the molecular diagnosis of resistance and drug discovery.

show abstract

Unique C-terminal region of Hap3 is required for methanol-regulated gene expression in the methylotrophic yeast Candida boidinii

et al. 2016

View full text Add to dashboard Cite

The Hap complex of the methylotrophic yeast Candida boidinii was found to be required for methanol-regulated gene expression. In this study, we performed functional characterization of CbHap3p, one of the Hap complex components in C. boidinii. Sequence alignment of Hap3 proteins revealed the presence of a unique extended C-terminal region, which is not present in Hap3p from Saccharomyces cerevisiae (ScHap3p), but is found in Hap3p proteins of methylotrophic yeasts. Deletion of the C-terminal region of CbHap3p (D256-292 or D107-237) diminished activation of methanol-regulated genes and abolished the ability to grow on methanol, but did not affect nuclear localization or DNA-binding ability. However, deletion of the N-terminal region of CbHap3p (D1-20) led to not only a growth defect on methanol and a decreased level of methanol-regulated gene expression, but also impaired nuclear localization and binding to methanol-regulated gene promoters. We also revealed that CbHap3p could complement the growth defect of the Schap3D strain on glycerol, although ScHap3p could not complement the growth defect of a Cbhap3D strain on methanol. We conclude that the unique C-terminal region of CbHap3p contributes to maximum activation of methanol-regulated genes, whilst the N-terminal region is required for nuclear localization and binding to DNA.

show abstract

The Region in a Subunit of theAspergillusCCAAT-Binding Protein Similar to the HAP4p-Recruiting Domain ofSaccharomyces cerevisiaeHap5p Is Not Essential for Transcriptional Enhancement

Cited by 4 publications

References 27 publications

Interaction of HapX with the CCAAT-binding complex—a novel mechanism of gene regulation by iron

Interaction of HapX with the CCAAT-binding complex—a novel mechanism of gene regulation by iron

Discovery of a hapE Mutation That Causes Azole Resistance in Aspergillus fumigatus through Whole Genome Sequencing and Sexual Crossing

Unique C-terminal region of Hap3 is required for methanol-regulated gene expression in the methylotrophic yeast Candida boidinii

Contact Info

Product

Resources

About