Characterization of a cdc14 null allele in Drosophila melanogaster

Cdc14 and PP2A Phosphatases Cooperate to Shape Phosphoproteome Dynamics during Mitotic Exit

Temporal control over protein phosphorylation and dephosphorylation is crucial for accurate chromosome segregation and for completion of the cell division cycle during exit from mitosis. In budding yeast, the Cdc14 phosphatase is thought to be a major regulator at this time, while in higher eukaryotes PP2A phosphatases take a dominant role. Here, we use time-resolved phosphoproteome analysis in budding yeast to evaluate the respective contributions of Cdc14, PP2A^Cdc55, and PP2A^Rts1. This reveals an overlapping requirement for all three phosphatases during mitotic progression. Our time-resolved phosphoproteome resource reveals how Cdc14 instructs the sequential pattern of phosphorylation changes, in part through preferential recognition of serine-based cyclin-dependent kinase (Cdk) substrates. PP2A^Cdc55 and PP2A^Rts1 in turn exhibit a broad substrate spectrum with some selectivity for phosphothreonines and a role for PP2A^Rts1 in sustaining Aurora kinase activity. These results illustrate synergy and coordination between phosphatases as they orchestrate phosphoproteome dynamics during mitotic progression.

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Cdc14, PP2A^Cdc55, and PP2A^Rts1 phosphatases cooperate during budding yeast mitosis

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Cdc14 targets serine Cdk motifs for rapid dephosphorylation

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PP2A^Cdc55 dephosphorylates Cdk and Plk substrates on threonine residues

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PP2A^Rts1 displays regulatory crosstalk with Aurora kinase

Conservation of Cdc14 phosphatase specificity in plant fungal pathogens: implications for antifungal development

Cdc14 protein phosphatases play an important role in plant infection by several fungal pathogens. This and other properties of Cdc14 enzymes make them an intriguing target for development of new antifungal crop treatments. Active site architecture and substrate specificity of Cdc14 from the model fungus Saccharomyces cerevisiae (ScCdc14) are well-defined and unique among characterized phosphatases. Cdc14 appears absent from some model plants. However, the extent of conservation of Cdc14 sequence, structure, and specificity in fungal plant pathogens is unknown. We addressed this by performing a comprehensive phylogenetic analysis of the Cdc14 family and comparing the conservation of active site structure and specificity among a sampling of plant pathogen Cdc14 homologs. We show that Cdc14 was lost in the common ancestor of angiosperm plants but is ubiquitous in ascomycete and basidiomycete fungi. The unique substrate specificity of ScCdc14 was invariant in homologs from eight diverse species of dikarya, suggesting it is conserved across the lineage. A synthetic substrate mimetic inhibited diverse fungal Cdc14 homologs with similar low µM Ki values, but had little effect on related phosphatases. Our results justify future exploration of Cdc14 as a broad spectrum antifungal target for plant protection.

The Multiple Roles of the Cdc14 Phosphatase in Cell Cycle Control

The Cdc14 phosphatase is a key regulator of mitosis in the budding yeast Saccharomyces cerevisiae. Cdc14 was initially described as playing an essential role in the control of cell cycle progression by promoting mitotic exit on the basis of its capacity to counteract the activity of the cyclin-dependent kinase Cdc28/Cdk1. A compiling body of evidence, however, has later demonstrated that this phosphatase plays other multiple roles in the regulation of mitosis at different cell cycle stages. Here, we summarize our current knowledge about the pivotal role of Cdc14 in cell cycle control, with a special focus in the most recently uncovered functions of the phosphatase.

Genetic Factors Influencing Sperm Competition

Females of many different species often mate with multiple males, creating opportunities for competition among their sperm. Although originally unappreciated, sperm competition is now considered a central form of post-copulatory male–male competition that biases fertilization. Assays of differences in sperm competitive ability between males, and interactions between females and males, have made it possible to infer some of the main mechanisms of sperm competition. Nevertheless, classical genetic approaches have encountered difficulties in identifying loci influencing sperm competitiveness while functional and comparative genomic methodologies, as well as genetic variant association studies, have uncovered some interesting candidate genes. We highlight how the systematic implementation of approaches that incorporate gene perturbation assays in experimental competitive settings, together with the monitoring of progeny output or sperm features and behavior, has allowed the identification of genes unambiguously linked to sperm competitiveness. The emerging portrait from 45 genes (33 from fruit flies, 8 from rodents, 2 from nematodes, and 2 from ants) is their remarkable breadth of biological roles exerted through males and females, the non-preponderance of sperm genes, and their overall pleiotropic nature.