Reference: Marini AM, et al. (2000) Cross-talk between ammonium transporters in yeast and interference by the soybean SAT1 protein. Mol Microbiol 35(2):378-85

Reference Help

Abstract

Ammonium uptake in the yeast Saccharomyces cerevisiae involves three membrane transporters (Mep1, -2 and -3) belonging to an evolutionarily conserved protein family that also includes the rhesus (Rh) blood group polypeptides of erythrocytes. We show here that, in the 26972c mutant defective in NH4+ transport, the Mep1 protein carrying an amino acid substitution in its cytoplasmic C-terminus trans-inhibits the closely related Mep3 protein. The same mutation introduced into Mep3 leads to loss of transport activity and this inactive form also trans-inhibits native Mep3. Inhibition of Mep3 is post-translational and can be overcome by overexpression. These results are consistent with a direct interaction between Mep proteins, as is the case for the Rh polypeptides. The soybean GmSAT1 gene, recently cloned for its ability to complement the NH4+ transport defect of strain 26972c, has been described as an NH4+ channel protein involved in the transfer of fixed nitrogen from the bacteroid to the host plant. We show here that GmSAT1 contains a sequence homologous to the DNA-binding domain of basic helix-loop-helix (bHLH) transcription factors. We also show that GmSAT1 restores NH4+ uptake in the yeast mutant by interfering with the inhibition of Mep3. Our results are not consistent with a direct role of GmSAT1 in ammonium transport.

Reference Type
Journal Article
Authors
Marini AM, Springael JY, Frommer WB, Andre B
Primary Lit For
Additional Lit For
Review For

Interaction Annotations

Increase the total number of rows showing on this page by using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details about experiment type and any other genes involved in the interaction.

Interactor Interactor Type Assay Annotation Action Modification Phenotype Source Reference

Gene Ontology Annotations

Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table.

Gene Gene Ontology Term Qualifier Aspect Method Evidence Source Assigned On Annotation Extension Reference

Phenotype Annotations

Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details.

Gene Phenotype Experiment Type Mutant Information Strain Background Chemical Details Reference

Regulation Annotations

Increase the total number of rows displayed on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; to filter the table by a specific experiment type, type a keyword into the Filter box (for example, “microarray”); download this table as a .txt file using the Download button or click Analyze to further view and analyze the list of target genes using GO Term Finder, GO Slim Mapper, SPELL, or YeastMine.

Regulator Target Experiment Assay Construct Conditions Strain Background Reference