title: Transcription of the Hsp30, Hsp70, and Hsp90 heat shock protein genes is modulated by the PalA protein in response to acid pH-sensing in the fungus Aspergillus nidulans.
abstract: Heat shock proteins are molecular chaperones linked to a myriad of physiological functions in both prokaryotes and eukaryotes. In this study, we show that the Aspergillus nidulans hsp30 (ANID_03555.1), hsp70 (ANID_05129.1), and hsp90 (ANID_08269.1) genes are preferentially expressed in an acidic milieu, whose expression is dependent on the palA (+) background under optimal temperature for fungal growth. Heat shock induction of these three hsp genes showed different patterns in response to extracellular pH changes in the palA(+) background. However, their accumulation upon heating for 2 h was almost unaffected by ambient pH changes in the palA (-) background. The PalA protein is a member of a conserved signaling cascade that is involved in the pH-mediated regulation of gene expression. Moreover, we identified several genes whose expression at pH 5.0 is also dependent on the palA (+) background. These results reveal novel aspects of the heat- and pH-sensing networks of A. nidulans.
authors.affiliation: Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Janaína S
authors.initials: JS
authors.lastname: Freitas
authors.forename: Emiliana M
authors.initials: EM
authors.lastname: Silva
authors.forename: Juliana
authors.initials: J
authors.lastname: Leal
authors.forename: Diana E
authors.initials: DE
authors.lastname: Gras
authors.forename: Nilce M
authors.initials: NM
authors.lastname: Martinez-Rossi
authors.forename: Lucilene Delazari
authors.initials: LD
authors.lastname: Dos Santos
authors.forename: Mario S
authors.initials: MS
authors.lastname: Palma
authors.forename: Antonio
authors.initials: A
authors.lastname: Rossi
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics* / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D050890:HSP30 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D014158:Transcription, Genetic
chemical_list: D005656:Fungal Proteins; D050890:HSP30 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins