Abstract: Compositions and methods are provided for enhancing the survival and promoting the maturation of mammalian oocytes, zygotes and preimplantation embryos. BDNF or BDNF agonists may be administered to an individual, or to cells in vitro, to enhance cellular maturation, embryo growth and fertilization. Accordingly, compositions comprising BDNF are herein presented for use in promoting in vivo oocyte maturation as well as for use as a component in culture media for promoting preimplantation maturation of zygotes and embryos, for instance, for use with in vitro fertilization procedures and for the production of stem cells. Additionally, compounds that interfere with the binding of BDNF to its receptor may be administered to an individual to prevent oocyte maturation, thereby acting as a contraceptive. The BNDF receptor, TrkB, and BDNF also find use in the screening and design of agonists and antagonists for use in the methods of the invention.

Abstract: High affinity relaxin receptors, polypeptide compositions related thereto, as well as nucleotide compositions encoding the same, are provided. These proteins, herein termed LGR7 and LGR8, are orphan leucine-repeat-containing, G protein-coupled receptors. These receptors have a wide and a unique tissue expression pattern. The receptors, particularly soluble fragments thereof, are useful as therapeutic agents capable of inhibiting the action of relaxin and lnsL3. The receptors and fragments thereof also find use in the screening and design of relaxin agonists and antagonists. Conditions treatable with relaxin agonists or antagonists include prevention or induction of labor, treatment of endometriosis, treatment of skin conditions such as scleroderma that require collagen or extracellular matrix remodelling. Additionally, relaxin has been implicated in the dilation of blood vessels' smooth muscle cells directly and through release of nitric oxide and atrial natriuretic peptide.

Abstract: A high affinity obestatin receptor is provided; the orphan receptor GPR39. The receptor mediates obestatin activities. The obestatin receptor (GPR39) and fragments thereof, particularly soluble fragments thereof, are useful as therapeutic agents capable of inhibiting the action of obestatin. In addition to use as a therapeutic agent, GPR39 polypeptides are utilized in screening and research methods for the determination of specific analogs, agonists, antagonist mimetics and agents that modulate production, metabolism, and disposition of GPR39 activities. Conditions treatable with GPR39 agonists or antagonists include regulation of weight, blood pressure and heart rate, and gastric empyting.

Abstract: The invention relates to polypeptides referred to herein as obestatin. Obestatin, analogs and mimetics thereof act in signaling pathways, and are shown to modulate hypertension and other cardiovascular parameters, and gastric emptying.

Abstract: The invention relates to nucleic acids and polypeptides referred to herein as cospeptin and cosmedin. Cospeptin, cosmedin, analogs and mimetics thereof act in signaling pathways, and are shown to modulate hypertension and other cardiovascular parameters, and gastric emptying. Cospeptin and cosmedin nucleic acid compositions find use in identifying homologous or related proteins and the DNA sequences encoding such proteins; in producing the polypeptide; and in studying associated physiological pathways.

Abstract: Compositions and methods are provided for modulating the survival and maturation of male and female mammalian germ cells. Compounds that interfere with the binding of INSL3 to its receptor, LGR8, are administered to an individual to prevent oocyte maturation, thereby acting as a contraceptive. INSL3 or INLS3 agonists are administered to an individual, or to cells in vitro, to enhance oocyte maturation, either for infertility treatment or for contraception. Compounds that interfere with the binding of INSL3 to its receptor are administered to an individual to enhance male germ cell apoptosis, thereby acting as a contraceptive. INSL3 or INLS3 agonists are administered to an individual, or to cells in vitro, to enhance sperm cell survival. LGR8 and INSL3 are useul separately or in combination in the screening and design of agonists and antagonists for use in the methods of the invention.

Abstract: Isolated nucleotide compositions and sequences are provided for LGR4, LGR5 and LGR7 genes. The nucleic acid compositions find use in identifying homologous or related genes; in identifying endogenous ligands for these receptors; in producing compositions that modulate the expression or function of its encoded protein; for gene therapy; mapping functional regions of the protein; and in studying associated physiological pathways. In addition, modulation of the gene activity in vivo is used for prophylactic and therapeutic purposes.