Structural analysis of neurofibromin by crosslinking mass spectrometry
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Orbitrap Fusion
ORGANISM(S): Homo Sapiens (human)
TISSUE(S): Cell Culture
SUBMITTER: 
Ralf Schittenhelm
LAB HEAD: Andrew Ellisdon
PROVIDER: PXD023593 | Pride | 2022-08-12
REPOSITORIES: Pride
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| HF1RS20200630_NF1_1.csv | Csv | |||
| HF1RS20200630_NF1_1_BS3.raw | Raw | |||
| HF1RS20200630_NF1_1_Ctl.raw | Raw | |||
| HF1RS20201126_NF1_23.csv | Csv | |||
| HF1RS20201126_NF1_2_BS3.raw | Raw |
Items per page: 5 1 - 5 of 16 |
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Project description:Aims/hypothesis AGEs are considered environmental contributors of type 1 diabetes, but the exact role AGEs play early in pathogenesis of the disease, remains unidentified. We aimed to reduce AGEs with the pharmacotherapy alagebrium chloride in MIN6N8 cells and early in life in NOD mice to determine its impact on beta cell immunogenicity, function, and disease progression. Methods MIN6N8 cells were cultured with AGEs with or without short-term alagebrium therapy to determine the effect on ER stress and beta cell antigen presentation via a reporter assay for protein responses in the unfolded protein response, the enzymatic activity of endoplasmic reticulum aminopeptidase-1 (ERAP1) and the immunopeptidome. To determine the effect of short-term alagebrium therapy on beta cells in vivo, female NOD mice were treated with alagebrium and insulin secretion, insulitis, and immune cell repertoire were studied. Adoptive transfer studies and diabetes progression studies were used to consider the impact of alagebrium on immune cell function and disease outcome. Results In MIN6N8 cells, alagebrium therapy inhibited the induction of endoplasmic reticulum (ER) stress and the activity of ERAP1 by AGE-modified proteins. Alagebrium treated-MIN6N8 cells did not change the MHC Class I presentation of known beta cell antigens but did induce proteomic changes related to ER homeostatic pathways. Prior to overt autoimmune diabetes, female NOD mice treated with alagebrium for 30-40 days had improved insulin secretion, reduced insulitis and amplified proportions of pancreatic CD8+ T cells, mature B cells and F4/80+ macrophages. Splenocytes from alagebrium-treated mice adoptively transferred disease to NODscid recipients and maintained interferon production in vitro. While partial protection of islets by alagebrium was seen following the adoptive transfer of activated NOD G9C8 transgenic TCR CD8+ T cells, alagebrium therapy in NOD mice did not reduce diabetes progression. Conclusions/interpretation Our data suggests that in experimental models of diabetes, short-term alagebrium treatment allows for beta cell improvement, and maintenance of immune cell function, which does not fully mitigate diabetes progression.
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2020-10-26 | PXD017958 | Pride
Project description:Cancer treatment decisions are increasingly guided by which specific genes are mutated within each patient’s tumor. For example, agents inhibiting the epidermal growth factor receptor (EGFR) benefit many colorectal cancer (CRC) patients, with the general exception of those whose tumor includes a KRAS mutation. However, among the various KRAS mutations, the G13D mutation behaves differently; for unknown reasons, CRC patients with the KRAS G13D mutation (also written KRASG13D) appear to benefit from the EGFR-blocking antibody cetuximab. Controversy surrounds this observation, because it appears to contradict the well-established mechanisms of EGFR signaling and of RAS mutations. Here, we identified a systems-level, mechanistic basis that explains why KRASG13D cancers respond to EGFR inhibition. We first investigated the problem with a computational model of RAS signaling, which unexpectedly revealed that the known biophysical differences between the three most common KRAS mutant proteins are sufficient to generate different sensitivities to inhibition. Computation and experimentation together revealed a non-intuitive, mutant-specific dependency of wild-type RAS activation by EGFR that is determined by the interaction strength between KRAS and the tumor suppressor neurofibromin (NF1). KRAS mutants that strongly interact with NF1 drive wild-type RAS activation in an EGFR independent manner through competitive inhibition of NF1, whereas KRAS G13D cells remain dependent upon EGFR for wild-type Ras activation because they cannot competitively inhibit NF1 due to a weak interaction between these two proteins. Overall, our work demonstrates how systems approaches enable mechanism-based inference in genomic medicine and can help identify patients for selective therapeutic strategies.
2020-05-27 | PXD014755 | Pride