Discovery of a potent deubiquitinase (DUB) small molecule activity‐based probe enables broad spectrum DUB activity profiling in living cells

Deubiquitinases (DUBs) are a family of >100 proteases that hydrolyze isopeptide bonds linking ubiquitin to protein substrates. This leads to reduced substrate degradation through the ubiquitin proteasome system. Deregulation of DUB activity has been implicated in many diseases, including cancer, neurodegeneration and auto-inflammation, and several have been recognized as attractive targets for therapeutic intervention. Ubiquitin-derived covalent activity-based probes (ABPs) provide a powerful tool for DUB activity profiling, but their large recognition element impedes cellular permeability and presents an unmet need for small molecule ABPs which can account for regulation of DUB activity in intact cells or organisms. Here, through comprehensive chemoproteomic warhead profiling, we identify cyanopyrrolidine (CNPy) probe IMP-2373 (12) as a small molecule pan-DUB ABP to monitor DUB activity in physiologically relevant live cells. Through proteomics and targeted assays, we demonstrate that IMP-2373 quantitatively engages more than 35 DUBs across a range of non-toxic concentrations in diverse cell lines. We further demonstrate its application to quantification of changes in intracellular DUB activity during pharmacological inhibition and during MYC deregulation in a model of B cell lymphoma. IMP-2373 thus offers a complementary tool to ubiquitin ABPs to monitor dynamic DUB activity in the context of disease-relevant phenotypes

Software Radar

This paper describes the design and implementation of a software defined phased radar receiver array developed for MIT Lincoln Laboratory. This receiver array was constructed with the USRP2, an inexpensive software defined radio to allow for scalability to larger receiver arrays. The team worked closely with Lincoln Laboratory staff to conduct time synchronization testing between the receivers in the array in order to characterize the internal oscillator drift of the radios. The team was able to get the receiver array synchronized within less than 2 ns. In addition to building the array, the team implemented radar processing algorithms in Matlab which had the ability to detect a target's range, radial velocity and direction from the receiver with an angular resolution of 20 degrees

Resources for Cycling-Interested Tourists in Copenhagen

The goal of this project was to develop material that aided in the creation of an accessible and dynamic compendium of cycling resources to make cycling more attractive and available to short-term tourists to Copenhagen. As part of the Danish Cyclists Federation's effort to develop a comprehensive information gateway to encourage Denmark's tourists to cycle, we collected and assessed information regarding bike rentals, safety, culture, routes, and guided tours, conducted interviews with cycling and tourism professionals, and researched Copenhagen tourist demographics. In addition to fully documenting our results in this report, our research helped us create a model information gateway with example content and recommendations for further improvement and development

Activation of the renal Na+:Cl- cotransporter by angiotensin II is a WNK4-dependent process

Pseudohypoaldosteronism type II is a salt-sensitive form of hypertension with hyperkalemia in humans caused by mutations in the with-no-lysine kinase 4 (WNK4). Several studies have shown that WNK4 modulates the activity of the renal Na(+)Cl(−) cotransporter, NCC. Because the renal consequences of WNK4 carrying pseudoaldosteronism type II mutations resemble the response to intravascular volume depletion (promotion of salt reabsorption without K(+) secretion), a condition that is associated with high angiotensin II (AngII) levels, it has been proposed that AngII signaling might affect WNK4 modulation of the NCC. In Xenopus laevis oocytes, WNK4 is required for modulation of NCC activity by AngII. To demonstrate that WNK4 is required in the AngII-mediated regulation of NCC in vivo, we used a total WNK4-knockout mouse strain (WNK4(−/−)). WNK4 mRNA and protein expression were absent in WNK4(−/−) mice, which exhibited a mild Gitelman-like syndrome, with normal blood pressure, increased plasma renin activity, and reduced NCC expression and phosphorylation at T-58. Immunohistochemistry revealed normal morphology of the distal convoluted tubule with reduced NCC expression. Low-salt diet or infusion of AngII for 4 d induced phosphorylation of STE20/SPS1-related proline/alanine-rich kinase (SPAK) and of NCC at S-383 and T-58, respectively, in WNK4(+/+) but not WNK4(−/−) mice. Thus, the absence of WNK4 in vivo precludes NCC and SPAK phosphorylation promoted by a low-salt diet or AngII infusion, suggesting that AngII action on the NCC occurs via a WNK4-SPAK–dependent signaling pathway. Additionally, stimulation of aldosterone secretion by AngII, but not by a high-K(+) diet, was impaired in WNK4(−/−) mice