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Weinberg, B. H.

Publications and source records attributed to Weinberg, B. H..

3 recordsLinked to original sources

Programmable Mixed-Signal Biocomputers in Mammalian Cells

Living cells perform sophisticated computations that guide them toward discrete states. Synthetic genetic circuits are powerful tools for programing these computations, where transcription-regulatory networks and DNA recombination are the two dominant paradigms for implementing these systems. While each strategy exhibits unique strengths and weaknesses, integrating both into one seamless design framework would enable advanced gene circuit designs intractable with either approach alone. Here, we present Computation via Recombinase Assisted Transcriptional Effectors (CREATE), which leverages site-specific recombination to perform robust logic on discreet computational layers and programmable transcription factors that connect these layers, allowing individual calculations to contribute toward larger operations. We demonstrate the functionality of CREATE by producing sophisticated circuits using a simple plug- and-play framework, including 189 2-input-3-output circuits, modular digital-to-analog signal converters, a 2-bit multiplier circuit, and a digital and analog mixed-signal generator. This work establishes CREATE as a versatile platform for programming complex signal processing systems capable of high-fidelity logic computation and tunable control over circuit output levels. One-Sentence SummaryWe present a minimal and robust genetic circuit platform for programming cells with sophisticated signal processing capabilities.

synthetic biology↗

High-performance chemical and light-inducible recombinases in mammalian cells and mice

Site-specific DNA recombinases are some of the most powerful genome engineering tools in biology. Chemical and light-inducible recombinases, in particular, enable spatiotemporal control of gene expression. However, the availability of inducible recombinases is scarce due to the challenge of engineering high performance systems with low basal activity and sufficient dynamic range. This limitation constrains the sophistication of genetic circuits and animal models that can be created. To expand the number of available inducible recombinases, here we present a library of >20 orthogonal split recombinases that can be inducibly dimerized and activated by various small molecules, light, and temperature in mammalian cells and mice.\n\nFurthermore, we have engineered inducible split Cre systems with better performance than existing inducible Cre systems. Using our orthogonal inducible recombinases, we created a \"genetic switchboard\" that can independently regulate the expression of 3 different cytokines in the same cell. To demonstrate novel capability with our split recombinases, we created a tripartite inducible Flp and a 4-Input AND gate. We have performed extensive quantitative characterization of the inducible recombinases for benchmarking their performances, including computation of distinguishability of outputs in terms of signal-to-noise ratio (SNR). To facilitate sharing of this set of reagents, we have deposited our library to Addgene. This library thus significantly expands capabilities for precise and multiplexed mammalian gene expression control.

synthetic biology↗

Inducible gene switches with memory in human T cells for cellular immunotherapy

Cell-based therapies that employ engineered T cells--including the expression of chimeric antigen receptors (CARs)--to target cancer cells have demonstrated promising responses in clinical trials. However, engineered T cell responses must be regulated to prevent severe side effects such as cytokine storms and off-target responses. Here we present a class of recombinase-based gene circuits that will enable inducible switching between two states of adoptive T cell therapy using an FDA-approved drug, creating a generalizable platform that can be used to control when and how strongly a gene is expressed. These circuits exhibit memory such that induced T cells will maintain any changes made even when the drug inducer is removed. This memory feature avoids prolonged drug inducer exposure, thus reducing the complexity and potential side effect associated with the drug inducer. We have utilized these circuits to control the expression of an anti-Her2-CAR, demonstrating the ability of these circuits to regulate CAR expression and T cell activity. We envision this platform can be extended to regulate other genes in T cell behavior for various adoptive T cell therapies.

synthetic biology↗