Cell Biology: Deciphering the ABCs of SLiMs in G1-CDK Signaling
| Autor: | Martha S. Cyert, Jagoree Roy |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
0301 basic medicine
Saccharomyces cerevisiae Proteins Saccharomyces cerevisiae Cell cycle Biology Sic1 Article General Biochemistry Genetics and Molecular Biology Cell biology 03 medical and health sciences 030104 developmental biology 0302 clinical medicine Docking (molecular) Cyclin-dependent kinase Cyclins biology.protein Substrate specificity Phosphorylation General Agricultural and Biological Sciences 030217 neurology & neurosurgery Signal Transduction |
| Zdroj: | Curr Biol |
| ISSN: | 0960-9822 |
| Popis: | Many protein-modifying enzymes recognize their substrates via docking motifs, but the range of functionally permissible motif sequences is often poorly defined. During eukaryotic cell division, cyclin-specific docking motifs help cyclin-dependent kinases (CDKs) phosphorylate different substrates at different stages, thus enforcing a temporally-ordered series of events. In budding yeast, CDK substrates with Leu/Pro-rich (LP) docking motifs are recognized by Cln1/2 cyclins in late G1 phase, yet the key sequence features of these motifs were unknown. Here we comprehensively analyzed LP motif requirements in vivo by combining a competitive growth assay with deep mutational scanning. We quantified the impact of all single-residue replacements in five different LP motifs, using six distinct G1 cyclins from diverse fungi including medical and agricultural pathogens. The results uncover substantial tolerance for deviations from the consensus sequence, plus requirements at some positions that are contingent on the favorability of other motif residues. They also reveal the basis for variations in functional potency among wild-type motifs, and allow derivation of a quantitative matrix that predicts the strength of other candidate motif sequences. Finally, we find that variation in docking motif potency can advance or delay the time at which CDK substrate phosphorylation occurs, and thereby control the temporal ordering of cell cycle regulation. The overall results provide a general method for surveying viable docking motif sequences and quantifying their potency in vivo, and they reveal how variations in docking strength can tune the degree and timing of regulatory modifications. |
| Databáze: | OpenAIRE |
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