The invention provides a platform and methods of using the platform for the regulation of the expression of a target gene using exposure to an aptamer ligand (for example, a small molecule). The platform features a polynucleotide gene regulation cassette that is placed in the target gene and includes a synthetic riboswitch positioned in the context of a 5 intron-alternative exon-3 intron. The riboswitch comprises an effector region and a sensor region (e.g., an aptamer that binds a small molecule ligand) such that the alternative exon is spliced into the target gene mRNA when the ligand is not present thereby preventing expression of the target gene. When the ligand is present, the alternative exon is not spliced into the target gene mRNA thereby providing expression of the target gene.

The present disclosure relates to systems, methods and compositions provided herein that include a compound protease. The compound protease can contain a protease domain, a cut site for another enzyme and an association domain. In some embodiments, the compound protease is part of a protein circuit.

The invention relates to the detection of the cofactor reduced nicotinamide adenine dinucleotide phosphate (NADPH). Provided is a sensor molecule for the resonance energy transfer (RET)-based detection of NADPH, the sensor comprising a segment A connected via a linker to a segment B, wherein each of segment A and segment B comprises a member of a RET pair comprising a donor moiety and an acceptor moiety, further characterized in that (i) segment A comprises a binding protein (BP) for NADPH, the BP being dihydrofolate reductase (DHFR; EC 1.5.1.3) or a functional homolog, fragment, derivative or variant thereof, showing the desired NADPH binding properties, and wherein the BP comprises a heterologous protein domain inserted at or replacing at least part of the region corresponding to positions (20) to (27) of E. coli DHFR, said heterologous protein domain comprising the member of the RET pair; (ii) segment B comprises a ligand (L) capable of intramolecular binding to said BP only in the presence of NADPH; such that the donor moiety and the acceptor moiety are in a suitable juxtaposition to yield a RET signal when L is bound to BP, and wherein NADPH-induced binding of L to BP results in an increase in RET efficiency.

The present disclosure relates to mutant polypeptides derived from Escherichia coli dihydrofolate reductase (DHFR) which can be fused to a polypeptide of interest for efficient conditional modulation of its activity. Also disclosed are polynucleotides encoding such mutant polypeptides, vectors comprising such polynucleotides, and the use of such polypeptides, polynucleotides and vectors for treating a disorder.

Methods of inserting genes into defined locations in the chromosomal DNA of cultured mammalian cell lines which are subject to gene amplification are disclosed. In particular, sequences of interest (e.g., genes encoding biotherapeutic proteins) are inserted proximal to selectable genes in amplifiable loci, and the transformed cells are subjected to selection to induce co-amplification of the selectable gene and the sequence of interest. The invention also relates to meganucleases, vectors and engineered cell lines necessary for performing the methods, to cell lines resulting from the application of the methods, and use of the cell lines to produce protein products of interest.

Materials and methods are provided which allowed for increased expression of a transfected gene of interest in a recombinant host cell.

The invention provides compositions including a fusion polypeptide and methods for making a fusion polypeptide that includes a COF1/CRBN-binding polypeptide, COF2/CRBN-binding polypeptide, or COF3/CRBN-binding polypeptide and a heterologous polypeptide of interest.

Provided herein is combination cancer therapy effected by administering a polymer-conjugated hyaluronidase, and a tumor-targeted taxane, and optionally a further chemotherapeutic agent such as a nucleoside analog. The combination therapy can be used in methods of treating cancers, and in particular solid tumor cancers.

Described are compounds of formula (I), or pharmaceutically acceptable salts thereof: (I) that are useful for control of protein expression with eDHFR tags and methods of controlling protein expression with such compounds, as well as kits comprising the compounds.

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The present disclosure relates to mutant polypeptides derived from Escherichia coli dihydrofolate reductase (DHFR) which can be fused to a polypeptide of interest for efficient conditional modulation of its activity. Also disclosed are polynucleotides encoding such mutant polypeptides, vectors comprising such polynucleotides, and the use of such polypeptides, polynucleotides and vectors for treating a disorder.