Proline 146 is critical to the structure, function and targeting of sod2, the Na+/H+ exchanger of Schizosaccharomyces pombe

Autor: Nicolas Touret, Larry Fliegel, Maxime Ndayizeye
Rok vydání: 2009
Předmět:
Models
Molecular
Mutant
medicine.disease_cause
Biochemistry
Protein Structure
Secondary
Green fluorescent protein
0302 clinical medicine
Trypsin
DNA
Fungal
Fluorescent Antibody Technique
Indirect
skin and connective tissue diseases
Site-directed mutagenesis
chemistry.chemical_classification
0303 health sciences
Mutation
Microscopy
Confocal
medicine.diagnostic_test
Recombinant Proteins
Amino acid
sod2
cardiovascular system
Cation binding
Sodium-Hydrogen Exchangers
Proline
Genes
Fungal
Molecular Sequence Data
Biophysics
Site specific mutagenesis
Biology
Biophysical Phenomena
03 medical and health sciences
Na+/H+ exchanger
Western blot
Schizosaccharomyces
medicine
Amino Acid Sequence
030304 developmental biology
salt tolerance
Ion Transport
Base Sequence
Sequence Homology
Amino Acid
Spectrophotometry
Atomic
Sodium
Wild type
Cell Biology
biology.organism_classification
Molecular biology
Amino Acid Substitution
chemistry
Schizosaccharomyces pombe
Mutagenesis
Site-Directed
Schizosaccharomyces pombe Proteins
030217 neurology & neurosurgery
Zdroj: Biochimica et Biophysica Acta (BBA) - Biomembranes. 1788:983-992
ISSN: 0005-2736
DOI: 10.1016/j.bbamem.2009.01.001
Popis: Sod2 is the Na + /H + exchanger of the fission yeast Schizosaccharomyces pombe that is principally responsible for salt tolerance. We examined the role of nine polar, membrane associated amino acids in the ability of the protein to confer salt tolerance in S. pombe . Wild type sod2 protein with a C-terminal GFP tag effectively rescued salt tolerance in S. pombe with deleted endogenous sod2. Sod2 protein with the mutations P163A, P183A, D298N, D389N, E390Q, E392Q and E397Q also conveyed salt tolerance as effectively as the wild type sod2 protein. In contrast, the mutation P146A resulted in a protein that did not convey salt tolerance nearly as effectively as the wild type and did not extrude Na + as well as the wild type. Mutation of Pro 146 to Ser, Asp or Lys had an intermediate effect. Mutation of Thr 142 to Ser resulted in a slightly defective protein. Western blot analysis showed that all mutant proteins were expressed at similar levels as wild type sod2 protein. Examination of the localization of the proteins showed that wild type and most sod2 mutants were present in the plasma membrane while the P146A mutant had an intracellular localization. Limited tryptic digestion suggested that the P146A sod2 protein had a change in conformation in comparison to the wild type protein. The results suggest that Pro 146 is an amino acid critical to sod2 structure, function and localization.
Databáze: OpenAIRE
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