Analysis of a novel calcium auxotrophy in Aspergillus nidulans
| Autor: | Herbert N. Arst, Ane Markina-Iñarrairaegui, Helen Findon, Eduardo A. Espeso, Ana-Maria Calcagno-Pizarelli, José Ramos, Anja Spielvogel, Miguel A. Peñalva, Tanya Indrakumar, José L. Martínez |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Vacuolar Proton-Translocating ATPases
Saccharomyces cerevisiae Proteins Antiporter Auxotrophy Saccharomyces cerevisiae chemistry.chemical_element Calcium Cation homeostasis Microbiology Aspergillus nidulans Article Ion pump 03 medical and health sciences Transcriptional regulation Genetics Vacuolation 030304 developmental biology 0303 health sciences biology 030306 microbiology Membrane transport protein Cell Membrane Membrane Transport Proteins Biological Transport Zinc Fingers biology.organism_classification Aspergillus Calcium transport Biochemistry chemistry Mutation Vacuoles biology.protein Transcription Factors |
| Zdroj: | Fungal Genetics and Biology |
| ISSN: | 1087-1845 |
| Popis: | In Aspergillus nidulans a combination of null mutations in halA, encoding a protein kinase, and sltA, encoding a zinc-finger transcription factor having no yeast homologues, results in an elevated calcium requirement ('calcium auxotrophy') without impairing net calcium uptake. sltA(-) (+/-halA(-)) mutations result in hypertrophy of the vacuolar system. In halA(-)sltA(-) (and sltA(-)) strains, transcript levels for pmcA and pmcB, encoding vacuolar Ca(2+)-ATPase homologues, are highly elevated, suggesting a regulatory relationship between vacuolar membrane area and certain vacuolar membrane ATPase levels. Deletion of both pmcA and pmcB strongly suppresses the 'calcium auxotrophy'. Therefore the 'calcium auxotrophy' possibly results from excessive vacuolar calcium sequestration, causing cytosolic calcium deprivation. Null mutations in nhaA, homologous to Saccharomyces cerevisiae NHA1, encoding a plasma membrane Na(+)/H(+) antiporter effluxing Na(+) and K(+), and a non-null mutation in trkB, homologous to S. cerevisiae TRK1, encoding a plasma membrane high affinity K(+) transporter, also suppress the calcium auxotrophy. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect