The subject invention pertains to transgenic non-human animals comprising a transgenic nucleotide sequence, integrated into the genome of the animals, comprising a nucleotide sequence encoding human FKBP51 operably linked to a tetracycline response element. In some embodiments, the transgenic animal comprises an additional transgenic nucleotide sequence, integrated into the genome of the animal, comprising a nucleotide sequence encoding a tetracycline transactivator (tTA) operably linked to a promoter; wherein the tTA is expressed upon activation of the promoter and binds the tetracycline response element, thereby causing expression of FKBP51. The invention also pertains to methods for screening for agents for the prevention and/or treatment of psychiatric disorders, such as depression.

Disclosed are methods, compositions, and systems for transforming silkworms to produce spider silk and analogs of spider silk. In certain embodiments, the method may include inserting a DNA sequence coding for at least a portion of a spider silk fibroin polypeptide, or an analog of a spider silk fibroin polypeptide, positioned between at least a portion of the 5′ and 3′ ends of a silkworm fibroin gene to generate a fusion gene construct having a sequence that encodes for a polypeptide comprising both spider silk fibroin and silkworm silk fibroin sequences. In certain embodiments, the fused gene is able to replace a native gene present in the silkworm such that the transformed silkworm expresses a polypeptide comprising a spider silk fibroin polypeptide, or an analog thereof, and expresses significantly less of the native silkworm silk.

A transgenic animal having a genome including a humanized immunoglobulin locus for securing the diversity of an antibody repertoire and a method of producing the same are disclosed. The transgenic non-human animal has two alleles of a humanized immunoglobulin gene, wherein the two alleles are hetero-alleles.

Antibodies comprising unpaired variable domains, e.g., heavy chain variable (VH) domains, for binding antigen. Antibody comprising two immunoglobulin (Ig) chains, wherein a first Ig chain comprises a variable domain and a constant domain, and a second Ig chain comprises a constant domain, wherein the second Ig chain lacks a variable domain, leaving the variable domain of the first Ig chain unpaired. The antibody may comprise two Ig heavy chains and two Ig light chains, each heavy chain comprising a VH domain and a constant region comprising a CH1 domain, and each light chain comprising a CL domain, wherein one or both light chains lack a VL domain, thereby leaving one or both VH domains unpaired. Non-human animals (e.g., mice) engineered to produce antibodies having unpaired VH domains, involving deletion of sequence coding for light chain variable (VL) domains. Use of unpaired VH domains to generate antigen-binding molecules.

The disclosure relates to Bt toxin resistance management. One embodiment relates to the isolation and characterization of polynucleotides and polypeptides corresponding to novel Bt toxin receptors. The polynucleotides and polypeptides are useful in identifying or designing novel Bt toxin receptor ligands including novel insecticidal toxins.

A pharmaceutical composition comprising a canine, feline or equine antibody having a lambda light chain or a functional fragment or functional derivative thereof, and a pharmaceutically acceptable excipient or carrier, for use or suitable for use in the prevention or treatment of disease ion a dog, cat, or horse, respectively.

A genetically modified non-human animal is provided, wherein the non-human animal expresses an antibody repertoire capable of pH dependent binding to antigens upon immunization. A genetically modified non-human animal is provided that expresses a single light chain variable domain derived from a single rearranged light chain variable region gene in the germline of the non-human animal, wherein the single rearranged light chain variable region gene comprises a substitution of at least one non-histidine encoding codon with a histidine encoding codon. Methods of making non-human animals that express antibodies comprising a histidine-containing universal light chain are provided.

Non-human animals, tissues, cells, and genetic material are provided that comprise a modification of an endogenous non-human heavy chain immunoglobulin sequence and that comprise an ADAM6 activity functional in a rodent (e.g., a mouse), wherein the non-human animals rearrange human immunoglobulin light chain gene segments in the context of heavy chain constant regions and express immunoglobulin-like molecules comprising human immunoglobulin light chain variable domains fused to heavy chain constant domains that are cognate with human immunoglobulin light chain variable domains fused to light chain constant domains.

Non-human animals comprising a human or humanized IL-4 and/or IL-4Rα nucleic acid sequence are provided. Non-human animals that comprise a replacement of the endogenous IL-4 gene and/or IL-4Rα gene with a human IL-4 gene and/or IL-4Rα gene in whole or in part, and methods for making and using the non-human animals, are described. Non-human animals comprising a human or humanized IL-4 gene under control of non-human IL-4 regulatory elements is also provided, including non-human animals that have a replacement of non-human IL-4-encoding sequence with human IL-4-encoding sequence at an endogenous non-human IL-4 locus. Non-human animals comprising a human or humanized IL-4Rα gene under control of non-human IL-4Rα regulatory elements is also provided, including non-human animals that have a replacement of non-human IL-4Rα-encoding sequence with human or humanized IL-4Rα-encoding sequence at an endogenous non-human C IL-4Rα locus. Non-human animals comprising human or humanized IL-4 gene and/or IL-4Rα sequences, wherein the non-human animals are rodents, e.g., mice or rats, are provided.

Genetically modified non-human animals and methods and compositions for making and using them are provided, wherein the genetic modification comprises a deletion in an immunoglobulin constant region CH1 gene (optionally a deletion in a hinge region) of an IgG, IgA, IgD, and/or IgE, and wherein the mouse is capable of expressing a functional IgM. Genetically modified mice are described, including mice having a functional IgM gene and modified to have a deletion of a CH1 domain and a hinge region in a heavy chain constant domain that is not an IgM, e.g., in an IgG heavy chain constant domain. Genetically modified mice that make human variable/mouse constant chimeric heavy chain antibodies (antibodies that lack a light chain), fully mouse heavy chain antibodies, or fully human heavy chain antibodies are provided.