The invention provides a method for generating a transgenic eukaryotic cell population having a modified human Rosa26 locus, which method includes introducing a functional DNA sequence into the human Rosa26 locus of starting eukaryotic cells. Also provided are targeting vectors useful in the method, as well as a cell population and a transgenic non-human animal comprising a modified human Rosa26 locus. Finally, the invention provides an isolated DNA sequence corresponding to the human Rosa26 locus.

The invention provides compositions and methods for performing mammalian cell genetics, e.g., genetic screens, using near-haploid cells. The invention further provides genes and gene products isolated using the inventive methods and methods of use thereof.

The present invention provides a method and components thereof of performing genetic modification under a drug-free environment. The method comprises the steps of generating a trapped mammalian cell library by trapper constructs (including the element of piggyBac terminal inverted repeats (TIRs)), reporter constructs, and helper constructs (including a sequence of an internal ribosomal entry site (IRES)). The present art allows: (1) to target & identify the silenced loci; (2) to separate genes with low-level expression at certain differentiation stages; (3) to evaluate the efficiency of gene targeting in the silent or repressed loci. The present invention avoids the biased gene targeting observed in the prior arts, and eliminates the needs of introducing antibiotic genes into the host genome which may lead to a potential threat of drifting antibiotic resistant genes into environment.

Methods and compositions for modifying the coding sequence of endogenous genes using rare-cutting endonucleases and transposases. The methods and compositions described herein can be used to modify the coding sequence of endogenous genes.

Provided herein are recombinant nucleic acids and viral vectors thereof encoding a SARS-CoV-2 spike protein that have been optimized for expression in mammalian cells.

Provided is a multicistronic retroviral vector genome having a first nucleic acid sequence upstream of at least one internal regulatory element, such that the level of genomic RNA available for packaging in the absence of rev, or a functional equivalent thereof, is increased.

The disclosure features compositions and methods for the treatment of sensorineural hearing loss and auditory neuropathy, particularly forms of the disease that are associated with a mutation in otoferlin (OTOF), by way of OTOF gene therapy. The disclosure provides a variety of compositions that include a first nucleic acid vector that contains a polynucleotide encoding an N-terminal portion of an OTOF isoform 5 protein and a second nucleic acid vector that contains a polynucleotide encoding a C-terminal portion of an OTOF isoform 5 protein. These vectors can be used to increase the expression of OTOF in a subject, such as a human subject suffering from sensorineural hearing loss.

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.

Provided herein are compositions that include at least two different nucleic acid vectors, where each of the at least two different vectors includes a coding sequence that encodes a different portion of an otoferlin protein, and the use of these compositions to treat hearing loss in a subject.

Provided herein are methods and compositions for expressing Otoferlin, e.g., utilizing adeno-associated viral (AAV) particles. Further provided herein are compositions of AAV particles comprising one or more polynucleotides encoding Otoferlin are codon optimized for expression in human cells. Such methods and compositions may be useful for treatment of diseases and disorders such as Deafness, Autosomal Recessive 9 (DFNB9). Also provided are kits comprising such compositions.