Abstract: The invention provides an S1P ligand-binding nucleic acid complex that is delivered to a target organ to regulate expression or editing of a target gene or a transcription or translation product thereof. The S1P ligand-binding nucleic acid complex includes a nucleic acid with an antisense oligonucleotide 12 to 30 nucleotides in length, and has a nucleic acid sequence complementary to a target transcription product, bound to a S1P ligand. The nucleic acid complex is useful for the treatment of a disease caused by such gene. The ligand-binding nucleic acid complex can be delivered to an organ, tissue, or cell in which the S1P receptor is expressed, such as the skeletal muscle, cardiac muscle, liver, kidney, lung, mammary gland, fat, podocyte, lymphocyte, or vascular endothelial cell.

Abstract: An object of the present invention is to provide a double-stranded nucleic acid complex having a reduced number of PS modifications in an antisense strand and maintaining an antisense effect. An optimal PS modification pattern for double-stranded nucleic acid complexes is disclosed. Such a nucleic acid complex comprising an antisense strand having an optimal PS modification pattern has a characteristic of having low toxicity and high bioavailability. The double-stranded nucleic acid complex comprising an antisense strand having an optimal PS modification pattern according to the present invention is useful when used as a nucleic acid drug that utilizes inhibition of expression of a specific gene (knockdown), activity that changes the function of coating or non-coding RNA for a specific gene, or activity that changes the function of RNA by inducing exon skipping during processing of pre-mRNA for a specific gene.

Abstract: A compound or its salts that inhibit the activity of the polypeptide or receptor of the present invention and the antibody of the present invention as well as the antisense DNA of the present invention are useful as, e.g., gastric acid secretion inhibitors, mucosa protectants, mineral absorption promoters, etc., which are less toxic and safe, and can be used as, e.g., agents for preventing/treating upper digestive tract disorders, antibacterial agents to Helicobacter pylori, etc. A compound or its salts that promote the activity of the polypeptide or receptor of the present invention, the polypeptide or receptor of the present invention and the DNA of the present invention can be used as, e.g., gastric acid secretion promoters and can be used as, e.g., agents for preventing/treating dyspepsia, bone metabolism disorders, anemia, etc. A compound or its salts that promote the activity of the polypeptide or receptor of the present invention, the polypeptide of the present invention, etc.

Abstract: A compound or its salts that inhibit the activity of the polypeptide or receptor of the present invention and the antibody of the present invention as well as the antisense DNA of the present invention are useful as, e.g., gastric acid secretion inhibitors, mucosa protectants, mineral absorption promoters, etc., which are less toxic and safe, and can be used as, e.g., agents for preventing/treating upper digestive tract disorders, antibacterial agents to Helicobacter pylori, etc. A compound or its salts that promote the activity of the polypeptide or receptor of the present invention, the polypeptide or receptor of the present invention and the DNA of the present invention can be used as, e.g., gastric acid secretion promoters and can be used as, e.g., agents for preventing/treating dyspepsia, bone metabolism disorders, anemia, etc. A compound or its salts that promote the activity of the polypeptide or receptor of the present invention, the polypeptide of the present invention, etc.