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Biology subjects

Hayward, P.

Publications and source records attributed to Hayward, P..

4 recordsLinked to original sources

Systematic molecular glue drug discovery with a high-throughput effector protein remodeling platform

Realising the promise of new medicines that operate through a targeted molecular glue-induced degradation mechanism requires systematic tools that can uncover the relevant principles of neomorphic protein-protein interactions. Whilst some monovalent glue degraders have been found through serendipity, the rules for small molecule attributes and the pairs or complexes of proteins that are amenable to drug-induced proximity control remain poorly articulated. Here we introduce a new approach to address this by using programmed libraries of intramolecularly edited proteins to expand protein surface landscapes and trigger new druggable interactions. We show that effector proteins, such as the E3 ligase Cereblon, can be engineered to provoke neomorphic activity by inducing the degradation of new client proteins and that these de novo interactions provide a blueprint from which new small molecule degraders can be built. As a demonstration of the approach, we use the platform to identify new non-IMiD molecular glue degraders of the oncology target GSPT1. SUMMARYO_LIMolecular glues are a highly important and promising new form of therapeutic agent, but rationalising their discovery has so far been impossible C_LIO_LIGlueSEEKER screening enables prospective monovalent drug discovery by using high-throughput deep mutational scanning to re-engineer the function of effector proteins like E3 ligases C_LIO_LIWe used this approach to enable the computational discovery of small molecule glues which degrade the oncology target GSPT1 and show how the technology can be used across new targets C_LI

bioengineering↗

Emergence of a node-like population within an in vitro derived Neural Mesodermal Progenitors (NMPs) population

The mammalian embryos Caudal Lateral Epiblast (CLE) harbours bipotent progenitors, called Neural Mesodermal Progenitors (NMPs), that contribute to the spinal cord and the paraxial mesoderm throughout axial elongation. Here we performed a single cell analysis of different in vitro NMPs populations produced either from embryonic stem cells (ESCs) or epiblast stem cells (EpiSCs) and compared them to E8.25 CLE mouse embryos. In our analysis of this region our findings challenge the notion that NMPs should coexpress Sox2 and T. We built a Support Vector Machine (SVM) based on the embryo CLE and use it as a classification model to analyse the in vitro NMP-like populations. We showed that ESCs derived NMPs are heterogeneous and contain few NMP-like cells, whereas EpiSCs derived NMPs, produce a high proportion of cells with the embryo NMP signature. Importantly, we found that the population from which the Epi-NMPs are derived in culture, contains a nodelike population, which is responsible for maintaining the expression of T in vitro. These results mimic the events in vivo and suggest a sequence of events for the NMPs emergence.

developmental biology↗

The chick caudo-lateral epiblast acts as a permissive niche for generating neuromesodermal progenitor behaviours

Neuromesodermal progenitors (NMps) are a population of bipotent progenitors that maintain competence to generate both spinal cord and paraxial mesoderm throughout the elongation of the posterior body axis. Recent studies have generated populations of NMp-like cells in culture and have been shown to differentiate to both neural and mesodermal cell fates when transplanted into either mouse or chick embryos. Here, we aim to compare the potential of mouse embryonic stem (ES) cell-derived progenitor populations to generate NMp behavior against both undifferentiated and differentiated populations. We define NMp behaviour as the ability of cells to i) contribute to a significant proportion of the anterior-posterior body axis, ii) enter into both posterior neural and somitic compartments and, iii) retain a proportion of the progenitor population within the posterior growth zone. We compare previously identified ES cell-derived NMp-like populations to undifferentiated mouse ES cells and find that they all display similar potentials to generate NMp behaviour in vivo. To assess whether this competence is lost upon further differentiation, we generated anterior and posterior embryonic cell types through the generation of 3D gastruloids and show that NMp competence is lost within the anterior (Brachyury negative) portion of the gastruloid. Taken together, this demonstrates that the chick caudo-lateral epiblast is a highly permissive environment for testing NMp competence and is therefore not suitable as a positive test of neuromesodermal progenitor identity (ie. specification). However, it does act as an appropriate system to test for the loss of NMp potential, and therefore offers insight as a functional test for the regulation of NMp competence in vivo.

developmental biology↗

An Epiblast Stem Cell derived multipotent progenitor population for axial extension

The Caudal Lateral Epiblast of mammalian embryos harbours bipotent progenitors that contribute to the spinal cord and the paraxial mesoderm in concert with the elongation of the body axis. These progenitors, called Neural Mesodermal Progenitors (NMPs) are identified as cells coexpressing Sox2 and T/Brachyury, a criterion used to derive NMP-like cells from Embryonic Stem Cells in vitro. However, these progenitors do not self renew, as embryonic NMPs do. Here we find that protocols that yield NMP-like cells in vitro first produce a multipotent population that, additional to NMPs, generates progenitors for the lateral plate and intermediate mesoderm. We show that Epiblast Stem Cells (EpiSCs) are an effective source for these multipotent progenitors that are further differentiated by a balance between BMP and Nodal signalling. Importantly, we show that NMP-like cells derived from EpiSCs self renew in vitro and exhibit a gene expression signature similar to that of their embryo counterparts.

developmental biology↗