Identification of members of the Aspergillus nidulans SREA regulon: genes involved in siderophore biosynthesis and utilization

Iron is an essential trace element for almost all organisms. However, an excess of this metal within cells can be deleterious on account of catalysis of cell-damaging hydroxyl radicals. Therefore, the concentration of iron within cells is tightly regulated and the primary control occurs by regulating its uptake. Under conditions of low iron availability, most fungi mobilize extracellular iron by excretion of low-molecular-mass ferric iron chelators, termed siderophores. Due to the potential impact of iron metabolism on fungal pathogenicity, a better insight into siderophore-mediated iron uptake is needed. In Aspergillus nidulans, siderophore biosynthesis and uptake are negatively regulated by the GATA-type transcription factor SREA. Hence, genes involved in siderophore biosynthesis and uptake are characterized by transcriptional induction under iron limitation in wild-type strain and de-repression in an sreA-deletion strain under conditions of sufficient iron supply. Such genes have been searched for using different strategies, e.g. differential mRNA display and expression analysis of candidate genes from various A. nidulans sequence databases. The identified genes presumably encode enzymes needed for siderophore biosynthesis, and transporters involved in siderophore uptake and/or excretion. The functional characterization of these genes will help to unravel the pathways involved in siderophore biosynthesis and uptake.

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Identification of Thyroid Hormones and Functional Characterization of Thyroid Hormone Receptor in the Pacific Oyster Crassostrea gigas Provide Insight into Evolution of the Thyroid Hormone System

PLoS ONE ◽

10.1371/journal.pone.0144991 ◽

2015 ◽

Vol 10 (12) ◽

pp. e0144991 ◽

Cited By ~ 22

Author(s):

Wen Huang ◽

Fei Xu ◽

Tao Qu ◽

Rui Zhang ◽

Li Li ◽

...

Keyword(s):

Thyroid Hormone ◽

Thyroid Hormones ◽

Hormone Receptor ◽

Pacific Oyster ◽

Thyroid Hormone Receptor ◽

Functional Characterization ◽

The Pacific ◽

Hormone System ◽

Insight Into

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Structural and functional characterization of a highly secreted α- l -arabinofuranosidase (GH62) from Aspergillus nidulans grown on sugarcane bagasse

Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics ◽

10.1016/j.bbapap.2017.09.001 ◽

2017 ◽

Vol 1865 (12) ◽

pp. 1758-1769 ◽

Cited By ~ 11

Author(s):

Fabiano Jares Contesini ◽

Marcelo Vizoná Liberato ◽

Marcelo Ventura Rubio ◽

Felipe Calzado ◽

Mariane Paludetti Zubieta ◽

...

Keyword(s):

Aspergillus Nidulans ◽

Sugarcane Bagasse ◽

Functional Characterization

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Structural and functional characterization of mouse U7 small nuclear RNA active in 3' processing of histone pre-mRNA.

Molecular and Cellular Biology ◽

10.1128/mcb.8.4.1518 ◽

1988 ◽

Vol 8 (4) ◽

pp. 1518-1524 ◽

Cited By ~ 41

Author(s):

D Soldati ◽

D Schümperli

Keyword(s):

Sea Urchin ◽

Functional Characterization ◽

Rnase H ◽

Primer Extension ◽

Small Nuclear Rna ◽

Nuclear Rna ◽

Processing Signal ◽

Insight Into

Oligonucleotides derived from the spacer element of the histone RNA 3' processing signal were used to characterize mouse U7 small nuclear RNA (snRNA), i.e., the snRNA component active in 3' processing of histone pre-mRNA. Under RNase H conditions, such oligonucleotides inhibited the processing reaction, indicating the formation of a DNA-RNA hybrid with a functional ribonucleoprotein component. Moreover, these oligonucleotides hybridized to a single nuclear RNA species of approximately 65 nucleotides. The sequence of this RNA was determined by primer extension experiments and was found to bear several structural similarities with sea urchin U7 snRNA. The comparison of mouse and sea urchin U7 snRNA structures yields some further insight into the mechanism of histone RNA 3' processing.

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Phylogenetic analysis of fungal aquaporins provides insight into their possible role in water transport of mycorrhizal associations

Botany ◽

10.1139/cjb-2013-0041 ◽

2013 ◽

Vol 91 (8) ◽

pp. 495-504 ◽

Cited By ~ 21

Author(s):

Hao Xu ◽

Janice E.K. Cooke ◽

Janusz J. Zwiazek

Keyword(s):

Water Transport ◽

Mycorrhizal Fungi ◽

Functional Characterization ◽

Arbuscular Mycorrhizal ◽

Gene Families ◽

Fungal Species ◽

Comparative Genomic ◽

Mycorrhizal Associations ◽

Insight Into

In mycorrhizal associations, water transport properties of the fungal hyphae may have a profound effect on water transport of the host plant. The importance of aquaporins, water-transporting members of the major intrinsic protein (MIP) family, in facilitating water transport has been widely acknowledged and extensively studied in plants. However, until recently, relatively little was known about the structure, function, and regulation of fungal MIPs. The rapid increase in the number of sequenced fungal genomes, including Laccaria bicolor and other mycorrhizal fungi, has enabled functional and comparative genomic investigations to delineate the role that fungal MIPs play in mycorrhizal-facilitated plant water transport. Phylogenic analysis of 229 fungal MIPs from 88 species revealed that MIPs of mycorrhizal fungal species fall into four clusters delineated by functionally characterized fungal MIPs: the orthodox aquaporins, the aquaglyceroporins, the facultative fungal aquaporins, and the X intrinsic proteins. This comparative genomics analysis, together with in silico structural characterization of predicted MIPs and recently published functional characterization of MIPs from a small number of ectomycorrhizal and arbuscular mycorrhizal species, provide new insight into MIP gene families of mycorrhizal fungi and possible roles for fungal aquaporins in water relations of mycorrhizal plant–fungus symbioses.

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Functional characterization of canine wild type glucocorticoid receptor and an insertional mutation in a dog

BMC Veterinary Research ◽

10.1186/s12917-019-2129-9 ◽

2019 ◽

Vol 15 (1) ◽

Author(s):

Kosei Yamanaka ◽

Masaru Okuda ◽

Takuya Mizuno

Keyword(s):

Glucocorticoid Receptor ◽

Cushing Syndrome ◽

Functional Characterization ◽

Wild Type ◽

Key Factors ◽

Truncated Form ◽

Glucocorticoid Sensitivity ◽

Almost All

Abstract Background Glucocorticoids, among the most widely utilized drugs in veterinary medicine, are employed to treat a wide variety of diseases; however, their use often induces adverse events in dogs. The efficacy of glucocorticoids usually depends on dosage, although differences in sensitivity to glucocorticoids in individual animals have been reported. Glucocorticoids bind to the cytoplasmic glucocorticoid receptor (GR), which is expressed in almost all cells. These receptors are key factors in determining individual sensitivity to glucocorticoids. This study examined individual differences in glucocorticoid sensitivity in dogs, focusing on reactivity of the GR to prednisolone. Results We first molecularly cloned the GR gene from a healthy dog. We discovered a mutant GR in a dog suspected to have iatrogenic Cushing syndrome. The mutant GR had extra nucleotides between exons 6 and 7, resulting in a truncated form of GR that was 98 amino acids shorter than the wild-type dog GR. The truncated GR exhibited very low reactivity to prednisolone, irrespective of concentration. Conclusions We have identified the truncated form of canine GR in a dog with iatrogenic Cushing syndrome. This truncated form showed the very less sensitivity to glucocorticoid in vitro, unfortunately, we could not elucidate its clinical significance. However, our data is a first report about the function of canine GR, and will facilitate the analysis of canine glucocorticoid sensitivity.

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Discovery and characterization of Hv1-type proton channels in reef-building corals.

10.1101/2021.04.08.439075 ◽

2021 ◽

Author(s):

Gisela Rangel-Tescas ◽

Cecilia Cervantes ◽

Miguel A Cervantes-Rocha ◽

Esteban Suarez-Delgado ◽

Anastazia T Banaszak ◽

...

Keyword(s):

Voltage Dependence ◽

Ph Regulation ◽

Functional Characterization ◽

Gene Encoding ◽

Proton Channels ◽

Gating Model ◽

Mechanistic Insight ◽

Voltage Dependent ◽

Insight Into

Voltage-dependent proton-permeable channels are membrane proteins mediating a number of important physiological functions. Here we report the presence of a gene encoding for Hv1 voltage-dependent, proton-permeable channels in two species of reef-building corals. We performed a characterization of their biophysical properties and found that these channels are fast-activating and modulated by the pH gradient in a manner that makes them interesting models for studying these processes more easily. We have also developed an allosteric gating model that provides mechanistic insight into the modulation of voltage-dependence by protons. This work also represents the first functional characterization of any ion channel in scleractinian corals. We discuss the implications of the presence of these channels in the membranes of coral cells in the calcification and pH regulation processes and possible consequences of ocean acidification related to the function of these channels.

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Urine Proteomics Profiling and Functional Characterization of Knee Osteoarthritis Using iTRAQ Technology

Hormone and Metabolic Research ◽

10.1055/a-1012-8571 ◽

2019 ◽

Vol 51 (11) ◽

pp. 735-740 ◽

Cited By ~ 1

Author(s):

Ke Xiao ◽

Lingjia Yu ◽

Lisi Zhu ◽

Zhihong Wu ◽

Xisheng Weng ◽

...

Keyword(s):

Functional Characterization ◽

Joint Function ◽

Urine Protein ◽

Western Blots ◽

Urine Proteomics ◽

Protein Levels ◽

Mass Spectrometry Technology ◽

Proteome Profile ◽

Insight Into

AbstractOsteoarthritis (OA) is a degenerative chronic disease affecting the whole joint structures. With the increment in life expectancy and aging population, OA has become one of the largest socioeconomic burdens, associated with pain and loss of joint function. However, early laboratory tests of OA are still lacking. Therefore, new diagnostic tests for this disease are urgently needed. In this study, to gain an insight into the pathogenesis and the potential biomarkers of OA, we implemented a comparative urine proteomics study on OA patients and health people using iTRAQ-based mass spectrometry technology. Western blotting was used to validate the relative changes in urine protein levels for four of the identified proteins. We constructed a comprehensive urine proteome profile of the OA patients and identified 102 proteins differently changed in abundance. Forty-six proteins were upregulated and 56 proteins were significantly downregulated in OA patients. Furthermore, the proteins, COL-4, MMP9, adiponectin, and BBOX1 were validated through Western blots, which can serve as valuable candidate biomarkers and help to illustrate the pathogenesis of OA. These findings may provide clues for promising biomarkers for the early diagnosis and also offer a theoretical basis for the early treatment of OA.

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Faculty Opinions recommendation of Functional characterization of Aspergillus nidulans homologues of Saccharomyces cerevisiae Spa2 and Bud6.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1032746.374439 ◽

2006 ◽

Author(s):

Gerhard Braus

Keyword(s):

Saccharomyces Cerevisiae ◽

Aspergillus Nidulans ◽

Functional Characterization

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AcpA, a member of the GPR1/FUN34/YaaH membrane protein family, is essential for acetate permease activity in the hyphal fungus Aspergillus nidulans

Biochemical Journal ◽

10.1042/bj20080124 ◽

2008 ◽

Vol 412 (3) ◽

pp. 485-493 ◽

Cited By ~ 19

Author(s):

Xavier Robellet ◽

Michel Flipphi ◽

Sylvine Pégot ◽

Andrew P. MacCabe ◽

Christian Vélot

Keyword(s):

Membrane Protein ◽

Aspergillus Nidulans ◽

Functional Characterization ◽

Protein Family ◽

Genome Data ◽

Low Concentrations ◽

Genes Encoding ◽

Acetate Utilization ◽

Utilization Pathway

In a previous study, alcS, a gene of the Aspergillus nidulans alc cluster, was shown to encode a protein that belongs to the GPR1/FUN34/YaaH membrane protein family. BLAST screening of the A. nidulans genome data identified additional genes encoding hypothetical proteins that could belong to this family. In this study we report the functional characterization of one of them, AN5226. Its expression is induced by ethanol and ethyl acetate (two inducers of the alc genes) and is mediated by the specific transcriptional activator of genes of the acetate-utilization pathway FacB. Growth of a null mutant (ΔAN5226) is notably affected when acetate is used as sole carbon source at low concentration and in a high pH medium, i.e. when protonated acetate, the form that can enter the cell by passive diffusion, is present in low amounts. Consistently, expression of AN5226 is also induced by acetate, but only when the latter is present at low concentrations. 14C-labelled acetate uptake experiments using germinating conidia demonstrate an essential role for AN5226 in mediated acetate transport. To our knowledge this report is the first to provide evidence for the identification of an acetate transporter in filamentous fungi. We have designated AN5226 as acpA (for acetate permease A).

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