Reference: Kominami K and Toda T (1997) Fission yeast WD-repeat protein pop1 regulates genome ploidy through ubiquitin-proteasome-mediated degradation of the CDK inhibitor Rum1 and the S-phase initiator Cdc18. Genes Dev 11(12):1548-60

Reference Help

Abstract


In fission yeast, maintenance of genome ploidy is controlled by at least two mechanisms. One operates through the Cdc2/Cdc13 kinase, which also involves the CDK inhibitor Rum1, and the other through the S-phase regulator Cdc18. By screening for sterile mutants that show increased ploidy, we have identified a new gene, pop1+, in mutants that become polyploid. The pop1 mutation shows a synthetic lethal interaction with the temperature-sensitive cdc2 or cdc13 mutation. In a pop1 mutant Rum1 and Cdc18 proteins become accumulated to high levels. The high ploidy phenotype in the pop1 mutant is dependent on the presence of the rum1+ gene, whereas the accumulation of Cdc18 is independent of Rum1. The predicted sequence of the Pop1 protein indicates that it belongs to a WD-repeat family with highest homology to budding yeast Cdc4, which participates in the ubiquitin-dependent pathway. Consistent with this notion, in a mutant of the 26S proteasome, higher molecular weight forms of Rum1 and Cdc18 are accumulated corresponding to polyubiquitination of these proteins. In the pop1 mutant, however, no ubiquitinated forms of these proteins are detected. Finally we show that Pop1 binds Cdc18 in vivo. We propose that Pop1 functions as a recognition factor for Rum1 and Cdc18, which are subsequently ubiquitinated and targeted to the 26S proteasome for degradation.

Reference Type
Comparative Study | Journal Article | Research Support, Non-U.S. Gov't
Authors
Kominami K, Toda T
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, or SPELL.

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