PUBLICATION
Conservation of affinity rather than sequence underlies a dynamic evolution of the motif-mediated p53/MDM2 interaction in ray-finned fishes
- Authors
- Mihalič, F., Arcila, D., Pettersson, M.E., Farkhondehkish, P., Andersson, E., Andersson, L., Betancur-R, R., Jemth, P.
- ID
- ZDB-PUB-240202-3
- Date
- 2024
- Source
- Molecular Biology and Evolution 41(2): (Journal)
- Registered Authors
- Keywords
- none
- MeSH Terms
-
- Animals
- Protein Structure, Tertiary
- Humans
- Protein Binding
- Proto-Oncogene Proteins c-mdm2/chemistry
- Proto-Oncogene Proteins c-mdm2/genetics
- Proto-Oncogene Proteins c-mdm2/metabolism
- Phylogeny
- Zebrafish*
- Tumor Suppressor Protein p53*/chemistry
- Tumor Suppressor Protein p53*/genetics
- Tumor Suppressor Protein p53*/metabolism
- PubMed
- 38301272 Full text @ Mol Bio Evol
Citation
Mihalič, F., Arcila, D., Pettersson, M.E., Farkhondehkish, P., Andersson, E., Andersson, L., Betancur-R, R., Jemth, P. (2024) Conservation of affinity rather than sequence underlies a dynamic evolution of the motif-mediated p53/MDM2 interaction in ray-finned fishes. Molecular Biology and Evolution. 41(2):.
Abstract
The transcription factor and cell cycle regulator p53 is marked for degradation by the ubiquitin ligase MDM2. The interaction between these two proteins is mediated by a conserved binding motif in the disordered p53 transactivation domain (p53TAD) and the folded SWIB domain in MDM2. The conserved motif in p53TAD from zebrafish displays a 20-fold weaker interaction with MDM2, compared to the interaction in human and chicken. To investigate this apparent difference, we tracked the molecular evolution of the p53TAD/MDM2 interaction among ray-finned fishes (Actinopterygii), the largest vertebrate clade. Intriguingly, phylogenetic analyses, ancestral sequence reconstructions, and binding experiments showed that different loss-of-affinity changes in the canonical binding motif within p53TAD have occurred repeatedly and convergently in different fish lineages, resulting in relatively low extant affinities (KD = 0.5-5 μM). However, for eleven different fish p53TAD/MDM2 interactions, non-conserved regions flanking the canonical motif increased the affinity 4 to 73-fold to be on par with the human interaction. Our findings suggest that compensating changes at conserved and non-conserved positions within the motif, as well as in flanking regions of low conservation, underlie a stabilizing selection of "functional affinity" in the p53TAD/MDM2 interaction. Such interplay complicates bioinformatic prediction of binding and call for experimental validation. Motif-mediated protein-protein interactions involving short binding motifs and folded interaction domains are very common across multicellular life. It is likely that evolution of affinity in motif-mediated interactions often involves an interplay between specific interactions made by conserved motif residues and non-specific interactions by non-conserved disordered regions.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping