Reference: Aström SU, et al. (1999) Genetic interactions between a null allele of the RIT1 gene encoding an initiator tRNA-specific modification enzyme and genes encoding translation factors in Saccharomyces cerevisiae. Mol Gen Genet 261(6):967-76

Reference Help

Abstract


The Saccharomyces cerevisiae gene RIT1 encodes a phospho-ribosyl transferase that exclusively modifies the initiator tRNA (tRNAMet(i)) by the addition of a 2'-O-ribosyl phosphate group to Adenosine 64. As a result, tRNAMet(i) is prevented from participating in the elongation steps of protein synthesis. We previously showed that the modification is not essential for the function of tRNAMet(i) in the initiation of translation, since rit1 null strains are viable and show no obvious growth defects. Here, we demonstrate that yeast strains in which a rit1 null allele is combined with mutations in any of the genes for the three subunits of eukaryotic initiation factor-2 (eIF-2), or with disruption alleles of two of the four initiator methionine tRNA (IMT) genes, show synergistic growth defects. A multicopy plasmid carrying an IMT gene can alleviate these defects. On the other hand, introduction of a high-copy-number plasmid carrying the TEF2 gene, which encodes the eukaryotic elongation factor 1alpha (eEF-1alpha), into rit1 null strains with two intact IMT genes had the opposite effect, indicating that increased levels of eEF-1alpha are deleterious to these strains, presumably due to sequestration of the unmodified met-tRNAMet(i) for elongation. Thus, under conditions in which the components of the ternary met-tRNAMet(i):GTP:eIF-2 complex become limiting or are functionally impaired, the presence of the 2'-O-ribosyl phosphate modification in tRNAMet(i) is important for the provision of adequate amounts of tRNAMet(i) for formation of this ternary complex.

Reference Type
Journal Article | Research Support, Non-U.S. Gov't | Research Support, U.S. Gov't, Non-P.H.S.
Authors
Aström SU, Nordlund ME, Erickson FL, Hannig EM, Byström AS
Primary Lit For
Additional Lit For
Review For

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

Disease 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 Disease Ontology Term Qualifier Evidence Method Source Assigned On 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 Direction Regulation Of Happens During Method Evidence

Post-translational Modifications


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 its 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.

Site Modification Modifier Reference

Interaction Annotations


Genetic Interactions

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 Allele Assay Annotation Action Phenotype SGA score P-value Source Reference

Physical Interactions

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 Assay Annotation Action Modification Source Reference

Functional Complementation 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 its 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 Species Gene ID Strain background Direction Details Source Reference