Evolution of an Amniote-Specific Mechanism for Modulating Ubiquitin Signaling via Phosphoregulation of the E2 Enzyme UBE2D3.
Abstract
Genetic variation in the enzymes that catalyze posttranslational modification of proteins is a potentially important source of phenotypic variation during evolution. Ubiquitination is one such modification that affects turnover of virtually all of the proteins in the cell in addition to roles in signaling and epigenetic regulation. UBE2D3 is a promiscuous E2 enzyme, which acts as an ubiquitin donor for E3 ligases that catalyze ubiquitination of developmentally important proteins. We have used protein sequence comparison of UBE2D3 orthologs to identify a position in the C-terminal α-helical region of UBE2D3 that is occupied by a conserved serine in amniotes and by alanine in anamniote vertebrate and invertebrate lineages. Acquisition of the serine (S138) in the common ancestor to modern amniotes created a phosphorylation site for Aurora B. Phosphorylation of S138 disrupts the structure of UBE2D3 and reduces the level of the protein in mouse embryonic stem cells (ESCs). Substitution of S138 with the anamniote alanine (S138A) increases the level of UBE2D3 in ESCs as well as being a gain of function early embryonic lethal mutation in mice. When mutant S138A ESCs were differentiated into extraembryonic primitive endoderm, levels of ...Continue Reading
References
Protein tyrosine kinase regulation by ubiquitination: critical roles of Cbl-family ubiquitin ligases
Methods Mentioned
Software Mentioned
Related Concepts
Related Feeds
Adult Stem Cells
Adult stem cells reside in unique niches that provide vital cues for their survival, self-renewal, and differentiation. They hold great promise for use in tissue repair and regeneration as a novel therapeutic strategies. Here is the latest research.