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Zollman, D.

Publications and source records attributed to Zollman, D..

3 recordsLinked to original sources

A method for the detection and enrichment of endogenous cereblon substrates

C-Terminal cyclic imides are posttranslational modifications on proteins that are recognized and removed by the E3 ligase substrate adapter cereblon (CRBN). Despite the observation of these modifications across the proteome by mass spectrometry-based proteomics, an orthogonal and generalizable method to visualize the C-terminal cyclic imide would enhance detection, sensitivity, and throughput of endogenous CRBN substrate characterization. Here we develop an antibody-like reagent, termed "cerebody," for visualizing and enriching C-terminal cyclic imide-modified proteins. We describe the engineering of CRBN derivatives to produce cerebody and use it to identify CRBN substrates by Western blot and enrichment from whole cell and tissue lysates. CRBN substrates identified by cerebody enrichment are mapped, validated, and further characterized for dependence on the C-terminal cyclic imide modification. These methods will accelerate the characterization of endogenous CRBN substrates and their regulation.

biochemistry↗

Design of a Cereblon construct for crystallographic and biophysical studies of protein degraders

The ubiquitin E3 ligase cereblon (CRBN) is the target of therapeutic drugs thalidomide and lenalidomide and is recruited by most targeted protein degraders (PROTACs and molecular glues) in clinical development. Biophysical and structural investigation of CRBN has been limited by current constructs that either require co-expression with the adaptor DDB1 or inadequately represent full-length protein, with high-resolution structures of degraders ternary complexes remaining rare. We present the design of CRBNmidi, a construct that readily expresses from E. coli with high yields as soluble, stable protein without DDB1. We benchmark CRBNmidi for wild-type functionality through a suite of biophysical techniques and solve high-resolution co-crystal structures of its binary and ternary complexes with degraders. We qualify CRBNmidi as an enabling tool to accelerate structure-based discovery of the next generation of CRBN based therapeutics. One sentence summaryA novel Cereblon construct (CRBNmidi) allows structural and biophysical enablement of ligand and degrader design

biochemistry↗

Targeting cancer with small molecule pan-KRAS degraders

Despite the high prevalence of cancers driven by KRAS mutations, to date only the G12C mutation has been clinically proven to be druggable via covalent targeting of the mutated cysteine amino acid residue (1). However, in many cancer indications other KRAS mutations, such as G12D and -V, are far more prevalent and small molecule concepts that can address a wider variety of oncogenic KRAS alleles are in high clinical demand (2). Here we show that a single small molecule can be used to simultaneously and potently degrade 13 out of 17 of the most prevalent oncogenic KRAS alleles, including those not yet tractable by inhibitors. Compared with inhibition, degradation of oncogenic KRAS results in more profound and sustained pathway modulation across a broad range of KRAS mutant cell lines. As a result, KRAS degraders inhibit growth of the majority of cancer cell lines driven by KRAS mutations while sparing models without genetic KRAS aberrations. Finally, we demonstrate that pharmacological degradation of oncogenic KRAS leads to tumour regression in vivo. Together, these findings unveil a new path towards addressing KRAS driven cancers with small molecule degraders. One-Sentence SummaryThe most prevalent KRAS variants which drive tumour growth in a major share of cancer patients can be targeted with a single small molecule degrader.

pharmacology and toxicology↗