Rodent model of mood disorders

Abstract

This disclosure relates to an animal model of human disease. More specifically, this disclosure relates to a rodent model of mood disorders such as unipolar depression and an anxiety disorder. Disclosed herein are genetically modified rodent animals that carry a humanized G protein-coupled receptor 156 (GPR156) gene that encodes a mutant human GPR156 protein comprising Asp at an amino acid position corresponding to position 533 in a full length wild type human GPR156 protein.

What is claimed is: 
     
         1 . A genetically modified rodent, whose genome comprises a humanized G protein-coupled receptor 156 (GPR156) gene at an endogenous rodent Gpr156 locus, wherein the humanized Gpr156 gene comprises a rodent Gpr156 nucleic acid portion and a human GPR156 nucleic acid portion, wherein the humanized Gpr156 gene encodes a wild type human GPR156 protein or a mutant human GPR156 protein comprising Asp at an amino acid position corresponding to position 533 in a full length wild type human GPR156 protein (E533D variation), and wherein expression of the humanized Gpr156 gene is under control of the rodent Gpr156 promoter at the endogenous rodent Gpr156 locus. 
     
     
         2 . The rodent of  claim 1 , wherein the humanized Gpr156 gene encodes a mutant human GPR156 protein comprising an E533D variation. 
     
     
         3 . The rodent of  claim 2 , wherein the human GPR156 nucleic acid portion comprises the ATG start codon through the stop codon of a human GPR156 gene, wherein the human GPR156 gene comprises nucleotides that encode the E533D variation. 
     
     
         4 . The rodent of  claim 3 , wherein the human GPR156 nucleic acid portion further comprises the 3′ UTR of the human GPR156 gene. 
     
     
         5 . The rodent of  claim 3  or  4 , wherein the rodent Gpr156 nucleic acid portion comprises a 5′ non-coding exonic sequence of a rodent Gpr156 gene. 
     
     
         6 . The rodent of  claim 5 , wherein the humanized Gpr156 gene further comprises a 3′ non-coding exonic sequence of a rodent Gpr156 gene. 
     
     
         7 . The rodent of  claim 2 , wherein the humanized Gpr156 gene is formed from a replacement of a rodent genomic fragment of an endogenous rodent Gpr156 gene at the endogenous rodent Gpr156 locus with the human GPR156 nucleic acid portion. 
     
     
         8 . The rodent of  claim 7 , wherein the human GPR156 nucleic acid portion comprises the ATG start codon through the stop codon of a human GPR156 gene, wherein the human GPR156 gene comprises nucleotides that encode the E533D variation. 
     
     
         9 . The rodent of  claim 8 , wherein the human GPR156 nucleic acid portion comprises a human genomic fragment comprising the ATG start codon through the last exon of the human GPR156 gene. 
     
     
         10 . The rodent of  claim 7 , wherein the rodent genomic fragment of the endogenous rodent Gpr156 gene being replaced comprises the ATG start codon through the stop codon of the endogenous rodent Gpr156 gene. 
     
     
         11 . The rodent according to any one of  claims 2 - 10 , wherein the mutant human GPR156 protein comprising an E533D variation comprises an amino acid sequence as set forth in SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8. 
     
     
         12 . The rodent of  claim 1 , wherein the humanized Gpr156 gene encodes a wild type human GPR156 protein. 
     
     
         13 . The rodent of  claim 12 , wherein the human GPR156 nucleic acid portion comprises the ATG start codon through the stop codon of a human GPR156 gene. 
     
     
         14 . The rodent of  claim 13 , wherein the human GPR156 nucleic acid portion further comprises the 3′ UTR of the human GPR156 gene. 
     
     
         15 . The rodent of  claim 13  or  14 , wherein the rodent Gpr156 nucleic acid portion comprises a 5′ non-coding exonic sequence of a rodent Gpr156 gene. 
     
     
         16 . The rodent of  claim 15 , wherein the humanized Gpr156 gene further comprises a 3′ non-coding exonic sequence of a rodent Gpr156 gene. 
     
     
         17 . The rodent of  claim 12 , wherein the humanized Gpr156 gene is formed from a replacement of a rodent genomic fragment of an endogenous rodent Gpr156 gene at the endogenous rodent Gpr156 locus with the human GPR156 nucleic acid portion. 
     
     
         18 . The rodent of  claim 17 , wherein the human GPR156 nucleic acid portion comprises the ATG start codon through the stop codon of a human GPR156 gene. 
     
     
         19 . The rodent of  claim 18 , wherein the human GPR156 nucleic acid portion comprises a human genomic fragment comprising the ATG start codon through the last exon of the human GPR156 gene. 
     
     
         20 . The rodent of  claim 17 , wherein the rodent genomic fragment of the endogenous rodent Gpr156 gene being replaced comprises the ATG start codon through the stop codon of the endogenous rodent Gpr156 gene. 
     
     
         21 . The rodent according to any one of  claims 12 - 20 , wherein the wild type human GPR156 protein comprises an amino acid sequence as set forth in SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4. 
     
     
         22 . The rodent according to any one of  claims 1 - 21 , wherein the rodent is heterozygous for the humanized Gpr156 gene. 
     
     
         23 . The rodent according to any one of  claims 1 - 21 , wherein the rodent is homozygous for the humanized Gpr156 gene. 
     
     
         24 . The rodent according to any one of  claims 1 - 23 , wherein the rodent is incapable of expressing an endogenous rodent Gpr156 protein. 
     
     
         25 . The rodent according to any one of  claims 1 - 24 , wherein the rodent is a mouse or a rat. 
     
     
         26 . An isolated rodent cell or tissue, whose genome comprises a humanized Gpr156 gene at an endogenous rodent Gpr156 locus, wherein the humanized Gpr156 gene comprises a rodent Gpr156 nucleic acid portion and a human GPR156 nucleic acid portion, wherein the humanized Gpr156 gene encodes a wild type human GPR156 protein or a mutant human GPR156 protein comprising an E533D variation, and wherein expression of the humanized Gpr156 gene is under control of the rodent Gpr156 promoter at the endogenous rodent Gpr156 locus. 
     
     
         27 . The isolated rodent cell or tissue of  claim 26 , wherein the human GPR156 nucleic acid portion comprises the ATG start codon through the stop codon of a human GPR156 gene, wherein the human GPR156 gene comprises nucleotides that encode either Glu or Asp at a position corresponding to position 533 in a full length wild type human GRP156 protein. 
     
     
         28 . The isolated rodent cell or tissue of  claim 27 , wherein the human GPR156 nucleic acid portion further comprises the 3′ UTR of the human GPR156 gene. 
     
     
         29 . The isolated rodent cell or tissue of  claim 27  or  28 , wherein the rodent Gpr156 nucleic acid portion comprises a 5′ non-coding exonic sequence of a rodent Gpr156 gene. 
     
     
         30 . The isolated rodent cell or tissue of  claim 29 , wherein the humanized Gpr156 gene further comprises a 3′ non-coding exonic sequence of a rodent Gpr156 gene. 
     
     
         31 . The isolated rodent cell or tissue of  claim 26 , wherein the humanized Gpr156 gene is formed from a replacement of a rodent genomic fragment of an endogenous rodent Gpr156 gene at the endogenous rodent Gpr156 locus with the human GPR156 nucleic acid portion. 
     
     
         32 . The isolated rodent cell or tissue of  claim 31 , wherein the human GPR156 nucleic acid portion comprises the ATG start codon through the stop codon of a human GPR156 gene, wherein the human GPR156 gene comprises nucleotides that encode either Glu or Asp at a position corresponding to position 533 in a full length wild type human GRP156 protein. 
     
     
         33 . The isolated rodent cell or tissue of  claim 32 , wherein the human GPR156 nucleic acid portion comprises a human genomic fragment comprising the ATG start codon through the last exon of the human GPR156 gene. 
     
     
         34 . The isolated rodent cell or tissue of  claim 31 , wherein the rodent genomic fragment of the endogenous rodent Gpr156 gene being replaced comprises the ATG start codon through the stop codon of the endogenous rodent Gpr156 gene. 
     
     
         35 . The isolated rodent cell or tissue of any one of  claims 26 - 34 , wherein the humanized Gpr156 gene encodes a mutant human GPR156 protein comprising an E533D variation, wherein the mutant human GPR156 protein comprises an amino acid sequence as set forth in SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8. 
     
     
         36 . The isolated rodent cell or tissue of any one of  claims 26 - 34 , wherein the humanized Gpr156 gene encodes a wild type human GPR156 protein, wherein the wild type human GPR156 protein comprises an amino acid sequence as set forth in SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4. 
     
     
         37 . The isolated rodent cell or tissue according to any one of  claims 26 - 36 , wherein the isolated rodent cell or tissue is heterozygous for the humanized Gpr156 gene. 
     
     
         38 . The isolated rodent cell or tissue according to any one of  claims 26 - 36 , wherein the isolated rodent cell or tissue is homozygous for the humanized Gpr156 gene. 
     
     
         39 . The isolated rodent cell or tissue according to any one of  claims 26 - 38 , wherein the rodent cell or tissue is incapable of expressing an endogenous rodent Gpr156 protein. 
     
     
         40 . The isolated rodent cell or tissue according to any one of  claims 26 - 39 , wherein the rodent cell is a rodent embryonic stem (ES) cell. 
     
     
         41 . The isolated rodent cell or tissue according to any one of  claims 26 - 40 , wherein the rodent cell or tissue is a mouse cell or tissue, or a rat cell or tissue. 
     
     
         42 . A method of making a genetically modified rodent, comprising:
 modifying a rodent genome so that the modified genome comprises a humanized Gpr156 gene at an endogenous rodent Gpr156 locus, wherein the humanized Gpr156 gene comprises a rodent Gpr156 nucleic acid portion and a human GPR156 nucleic acid portion, wherein the humanized Gpr156 gene encodes a wild type human GPR156 protein or a mutant human GPR156 protein comprising an E533D variation, and wherein expression of the humanized Gpr156 gene is under control of the rodent Gpr156 promoter at the endogenous rodent Gpr156 locus; and   obtaining a genetically modified rodent comprising the modified genome.   
     
     
         43 . The method of  claim 42 , wherein the rodent genome is modified by a process comprising
 (a) introducing a targeting vector into a rodent ES cell, wherein the targeting vector comprises the human GPR156 nucleic acid portion to be integrated into an endogenous rodent Gpr156 locus thereby forming a humanized Gpr156 gene an endogenous rodent Gpr156 locus;   (b) obtaining a genetically modified rodent ES cell whose genome comprises the humanized Gpr156 gene; and   (c) making a rodent using the genetically modified rodent ES cell of (b).   
     
     
         44 . The method of  claim 43 , wherein the human GPR156 nucleic acid portion comprises a human genomic fragment comprising the ATG start codon through the stop codon of a human GPR156 gene, wherein the human GPR156 gene comprises nucleotides that encode either Glu or Asp at an amino acid position corresponding to position 533 in a full length wild type human GPR156 protein. 
     
     
         45 . The method of  claim 44 , wherein the human GPR156 nucleic acid portion further comprises the 3′ UTR of the human GPR156 gene. 
     
     
         46 . The method of  claim 44  or  45 , wherein the rodent Gpr156 nucleic acid portion comprises a 5′ non-coding exonic sequence of the endogenous rodent Gpr156 gene. 
     
     
         47 . The method of  claim 46 , wherein the humanized Gpr156 gene further comprises a 3′ non-coding exonic sequence of a rodent Gpr156 gene. 
     
     
         48 . The method of  claim 43 , wherein the humanized Gpr156 gene is formed from a replacement of a rodent genomic fragment of an endogenous rodent Gpr156 gene at the endogenous rodent Gpr156 locus with the human GPR156 nucleic acid portion. 
     
     
         49 . The method of  claim 48 , wherein the human GPR156 nucleic acid portion comprises a human genomic fragment comprising the ATG start codon through the stop codon of a human GPR156 gene, wherein the human GPR156 gene comprises nucleotides that encode Glu or Asp at an amino acid position corresponding to position 533 in a full length wild type human GPR156 protein. 
     
     
         50 . The method of  claim 49 , wherein the human genomic fragment comprises the ATG start codon through the last exon of the human GPR156 gene. 
     
     
         51 . The method of  claim 48 , wherein the rodent genomic fragment of the endogenous rodent Gpr156 gene being replaced comprises the ATG start codon through the stop codon of the endogenous rodent Gpr156 gene. 
     
     
         52 . The method according to any one of  claims 42 - 51 , wherein the rodent is heterozygous for the humanized Gpr156 gene. 
     
     
         53 . The method according to any one of  claims 42 - 51 , wherein the rodent is homozygous for the humanized Gpr156 gene. 
     
     
         54 . The method according to any one of  claims 42 - 53 , wherein the rodent is incapable of expressing an endogenous rodent Gpr156 protein. 
     
     
         55 . The method according to any one of  claims 42 - 54 , wherein the rodent is a mouse or a rat. 
     
     
         56 . A targeting vector, comprising
 a human GPR156 nucleic acid to be integrated into a rodent Gpr156 gene at an endogenous rodent Gpr156 locus, flanked by a 5′ nucleotide sequence and a 3′ nucleotide sequence that are homologous to nucleotide sequences at the rodent Gpr156 locus,   wherein integration of the human GPR156 nucleic acid into the rodent Gpr156 gene results in a replacement of a rodent genomic fragment of an endogenous rodent Gpr156 gene at the endogenous rodent Gpr156 locus with the human GPR156 nucleic acid to form a humanized Gpr156 gene,   wherein the human GPR156 nucleic acid encodes either a wild type human GPR156 protein or a mutant human GPR156 protein comprising an E533D variation and   wherein expression of the humanized Gpr156 gene is under control of the rodent Gpr156 promoter at the endogenous rodent Gpr156 locus.   
     
     
         57 . The targeting vector of  claim 56 , wherein the human GPR156 nucleic acid comprises the ATG start codon through the stop codon of a human GPR156 gene, wherein the human GPR156 gene comprises nucleotides that encode either Glu or Asp at an amino acid position corresponding to position 533 in a full length wild type human GPR156 protein. 
     
     
         58 . The targeting vector of  claim 47 , wherein the human GPR156 nucleic acid comprises the ATG start codon through the last exon of the human GPR156 gene. 
     
     
         59 . The targeting vector of  claim 58 , wherein the rodent genomic fragment of the endogenous rodent Gpr156 gene being replaced comprises the ATG start codon through the stop codon of the endogenous rodent Gpr156 gene. 
     
     
         60 . The targeting vector according to any one of  claims 56 - 59 , wherein the rodent is a mouse or a rat. 
     
     
         61 . A method, comprising breeding a first rodent whose genome comprises a humanized Gpr156 gene at an endogenous rodent Gpr156 locus with a second rodent, resulting in a progeny mouse whose genome comprises the a humanized Gpr156 gene, wherein the humanized Gpr156 gene encodes a wild type human GPR156 protein or a mutant human GPR156 protein comprising an E533D variation, and wherein expression of the humanized Gpr156 gene is under control of the rodent Gpr156 promoter at the endogenous rodent Gpr156 locus. 
     
     
         62 . The method of  claim 61 , wherein the first rodent and the second rodent are mice, or the first rodent and the second rodent are rats. 
     
     
         63 . A progeny rodent whose genome comprises a humanized Gpr156 gene at an endogenous rodent Gpr156 locus, wherein the progeny rodent is produced by a method comprising breeding a first rodent whose genome comprises the humanized Gpr156 gene with a second rodent, wherein the humanized Gpr156 gene encodes a wild type human GPR156 protein or a mutant human GPR156 protein comprising an E533D variation, and wherein expression of the humanized Gpr156 gene is under control of the rodent Gpr156 promoter at the endogenous rodent Gpr156 locus. 
     
     
         64 . The progeny rodent of  claim 63 , wherein the progeny rodent is heterozygous for the humanized Gpr156 gene. 
     
     
         65 . The progeny rodent of  claim 63 , wherein the progeny rodent is homozygous for the humanized Gpr156 gene. 
     
     
         66 . The progeny rodent according to any one of  claims 63 - 65 , wherein the progeny rodent is a mouse or a rat. 
     
     
         67 . A rodent, whose genome comprises genetically modified Gpr156 locus, wherein the genetic modification comprises a deletion in an endogenous rodent Gpr156 gene and optionally an insertion of a reporter gene, wherein the reporter gene is operably linked to the endogenous rodent Gpr156 promoter at the locus. 
     
     
         68 . The rodent of  claim 67 , wherein the genomic fragment beginning from the nucleotide after the start codon through a subsequent coding exon has been deleted, and wherein the reporter gene is operably linked to the start codon of the endogenous rodent Gpr156 gene. 
     
     
         69 . The rodent of  claim 67  or  68 , wherein the reporter gene is LacZ, or a gene encoding a protein selected the group consisting of luciferase, green fluorescent protein (GFP), enhanced GFP (eGFP), cyan fluorescent protein (CFP), yellow fluorescent protein (YFP), enhanced yellow fluorescent protein (eYFP), blue fluorescent protein (BFP), enhanced blue fluorescent protein (eBFP), DsRed, and MmGFP. 
     
     
         70 . The rodent of any one of  claims 68 - 69 , wherein expression of the reporter gene resembles the expression pattern of an endogenous rodent Gpr156 gene. 
     
     
         71 . The rodent of any one of  claims 67 - 70 , wherein the rodent is homozygous for the genetic modification. 
     
     
         72 . The rodent of any one of  claims 67 - 70 , wherein the rodent is heterozygous for the genetic modification. 
     
     
         73 . The rodent of any one of  claims 67 - 72 , wherein the rodent is a rat or a mouse. 
     
     
         74 . A method of testing the effect of an agent for treating unipolar depression or an anxiety disorder, comprising
 administering the agent to a rodent according to any one of  claim 2 - 11  or  22 - 25 ;   subjecting the rodent to a test to assess behavior in the rodent indicative of unipolar depression or the anxiety disorder, and   determining whether the agent has any effect on the behavior in the rodent.   
     
     
         75 . The method of  claim 74 , wherein the test is a forced swim test. 
     
     
         76 . The method of  claim 74 , wherein the test is a marble burying test. 
     
     
         77 . A rodent model of mood disorders, comprising a genetically modified rodent according to any one of  claim 2 - 11  or  22 - 25 . 
     
     
         78 . The rodent model of  claim 77 , further comprising a genetically modified rodent according to any one of  claim 12 - 21  or  22 - 25 . 
     
     
         79 . The rodent model of  claim 77  or  78 , further comprising a genetically modified rodent according to any one of  claims 67 - 73 .