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Moorhead, G.

Publications and source records attributed to Moorhead, G..

2 recordsLinked to original sources

Mechanistic modeling and machine learning identifies optimum radiotherapy schedules to prevent treatment-induced metastasis

Lung cancer patients often experience increased metastasis formation after radiotherapy. However, it is incompletely understood whether radiation affects the migratory behavior of tumor cells and how altered radiotherapy schedules might mitigate this risk. To address these questions, we performed live-cell microscopy experiments to profile changes in cell migration during radiation across 12 cancer cell lines and developed a predictive computational modeling platform describing tumor volume and dissemination during radiotherapy. Using this platform, we identified optimal fractionation schedules and then performed extensive in silico clinical trials, establishing that our optimized schedules substantially reduce metastatic seeding relative to the standard of care schedule. Training transformer models on the in silico clinical trial data enabled us to recover mechanistic parameters with high accuracy, demonstrating that the features determining optimal radiotherapy can be inferred from longitudinal tumor data. Our integrative predictive approach enables the rational design of optimum clinical trials across indications.

bioinformatics↗

Phospho-proteomics identifies D-group MAP kinases as substrates of the Arabidopsis tyrosine phosphatase RLPH2

Despite being one of the few bona fide plant tyrosine phosphatases, RLPH2 has no known substrates. Utilizing phospho-proteomics, we identified the activation loop phospho-tyrosine of several D-group mitogen activated protein kinases (MPKs) as potential RLPH2 substrates. All Arabidopsis D-Group MPKs possess a TDY activation loop phosphorylation motif, whereas other MPKs (Groups A, B and C) contain a TEY motif. Our findings reveal that RLPH2 has a strong preference for aspartate (D) in the TXY motif, providing specificity for RLPH2 to exclusively target and dephosphorylate the D-Group MPKs. Additionally, D-Group MPKs contain a unique activation loop insertion that conforms to a protein phosphatase 1 (PP1) binding motif, with findings presented here confirming Arabidopsis PP1 phosphatases dock at this site. Intriguingly, only D-group MPKs among all identified Arabidopsis protein kinases possess this PP1 recruiting motif. Using multiple RLPH2 deficient plant lines, we demonstrate that RLPH2 represses seed dormancy release. Overall, this work highlights the power of phospho-proteomics in identifying substrates of this novel plant tyrosine phosphatase, while also revealing new complexities in the interactions between MPK activation loops and multiple phospho-mediated cell signaling events. One sentence summaryPhospho-proteomic analysis reveals Arabidopsis tyrosine phosphatase RLPH2 dephosphorylates the activation loop of D-Group mitogen activated protein kinases.

plant biology↗