Abstract: Disclosed herein include systems, methods, compositions, and kits for in situ readout of barcodes, such as DNA barcodes. Barcode constructs containing a promoter (e.g., a phage promoter) that is inactive in live cells can be integrated in the genomes of cells. Cells can be fixed, and phage RNA polymerase can be used for transcription of the barcode to RNA transcripts. The RNA transcripts can be detected using, for example, fluorescent imaging and used to determine barcode sequences.

Abstract: Disclosed herein include methods, compositions, and systems suitable for use in delivering a polynucleotide to a target cell of a subject in need thereof. In some embodiments, a viral vector comprises a polynucleotide encoding nucleoprotein (N), phosphoprotein (P), matrix protein (M), RNA-dependent RNA polymerase (L), and one or more transgenes. The viral vector can comprise one or more of a conditionally stable fusion protein, a protease fusion protein, a degron fusion protein, and/or a glycoprotein derived of another species than the viral vector polynucleotide to enable control of viral vector transduction and/or replication.

Abstract: Disclosed herein include systems, methods, compositions, and kits for in situ readout of barcodes, such as DNA barcodes. Barcode constructs containing a promoter (e.g., a phage promoter) that is inactive in live cells can be integrated in the genomes of cells. Cells can be fixed, and phage RNA polymerase can be used for transcription of the barcode to RNA transcripts. The RNA transcripts can be detected using, for example, fluorescent imaging and used to determine barcode sequences.

Abstract: Disclosed herein include circuits, compositions, nucleic acids, populations, systems, and methods enabling single circuits to generate multiple molecularly and functionally distinct states that are each stable across multiple cell division cycles. Synthetic circuits provided herein can stably exist in multiple distinct states characterized by differences in the concentrations and expression levels of its components. In the absence of changes to the external environment, each of these states can be stable. In some embodiments, transcription factors provided herein activate when dimerized, and show much weaker activity as monomers. In some embodiments, each transcription factor homodimer activates expression of its own gene. In some embodiments, transcription factors can form mixed heterodimers with one another that do not strongly activate any genes in the circuit.

Abstract: Disclosed herein include circuits, compositions, nucleic acids, populations, systems, and methods enabling cells to sense, control, and/or respond to their own population size. In some embodiments, an orthogonal communication channel allows specific communication between engineered cells. Also described herein, in some embodiments, is an evolutionarily robust ‘paradoxical’ regulatory circuit architecture in which orthogonal signals both stimulate and inhibit net cell growth at different signal concentrations. In some embodiments, engineered cells autonomously reach designed densities and/or activate therapeutic or safety programs at specific density thresholds. Methods of treatment are also provided in some embodiments.

Abstract: Disclosed herein include methods, compositions, and kits suitable for robust and tunable control of payload gene expression. Some embodiments provide rationally designed circuits, including miRNA-level and/or protein-level incoherent feed-forward loop circuits, that maintain the expression of a payload at an efficacious level. The circuit can comprise a promoter operably linked to a polynucleotide encoding a fusion protein comprising a payload protein, a protease, and one or more self-cleaving peptide sequences. The payload protein can comprise a degron and a cut site the protease is capable of cutting to expose the degron. The circuit can comprise a promoter operably linked to a polynucleotide comprising a payload gene, a silencer effector cassette, and one or more silencer effector binding sequences.

Abstract: Disclosed herein include methods, compositions, and kits suitable for use in thresholding of protein signals. There are provided, in some embodiments, synthetic protein circuits that respond to inputs only above or below a certain threshold concentration. In some embodiments, the threshold value itself is tunable. Methods of treating a disease or disorder characterized by aberrant signaling are provided in some embodiments.

Abstract: Disclosed herein include systems, methods, compositions, and kits for in situ readout of barcodes, such as DNA barcodes. Barcode constructs containing a promoter (e.g., a phage promoter) that is inactive in live cells can be integrated in the genomes of cells. Cells can be fixed, and phage RNA polymerase can be used for transcription of the barcode to RNA transcripts. The RNA transcripts can be detected using, for example, fluorescent imaging and used to determine barcode sequences.

Abstract: Disclosed herein include methods, compositions, and kits suitable for use in detecting the activation level of a signal transducer. In some embodiments, there are provided synthetic protein circuits wherein recruitment of synthetic protein circuit components to an association location upon activation of a signal transducer generates an active effector protein. The effector protein can be configured to carry out a variety of functions when in an active state, such as, for example, inducing cell death. Methods of treating a disease or disorder characterized by aberrant signaling are provided in some embodiments.

Abstract: Disclosed herein include methods, compositions, and systems suitable for use in delivering a polynucleotide to a target cell of a subject in need thereof. In some embodiments, a viral vector comprises a polynucleotide encoding nucleoprotein (N), phosphoprotein (P), matrix protein (M), RNA-dependent RNA polymerase (L), and one or more transgenes. The viral vector can comprise one or more of a conditionally stable fusion protein, a protease fusion protein, a degron fusion protein, and/or a glycoprotein derived of another species than the viral vector polynucleotide to enable control of viral vector transduction and/or replication.

Abstract: Methods and systems for recording and mapping lineage information and molecular events in individual cells are provided. Molecular changes, which may result from random or specific molecular events, are introduced to defined regions in cells over multiple cell cycle generations. Techniques such as fluorescent imaging are applied to track and identify the molecular changes before such information is used for lineage analysis or for identifying key processes and key players in cellular pathways.

Abstract: Methods and systems for recording and mapping lineage information and molecular events in individual cells are provided. Molecular changes, which may result from random or specific molecular events, are introduced to defined regions in cells over multiple cell cycle generations. Techniques such as fluorescent imaging are applied to track and identify the molecular changes before such information is used for lineage analysis or for identifying key processes and key players in cellular pathways.