Alternative splicing generates isoforms of human neuron-derived orphan receptor-1 (NOR-1) mRNA.
Neuron-derived orphan receptor-1 (NOR-1) is a novel member of the Nur77/NGFI-B subfamily within the nuclear receptor superfamily. Recently, several proteins closely related to NOR-1 have been described. To elucidate the relationships between NOR-1 and these closely related proteins, we analyzed the human NOR-1 gene and its transcripts by molecular cloning. We identified two variant NOR-1 transcripts in human skeletal muscles. One variant has a different 5'-untranslated region, and the other lacks C-terminal amino acid sequences corresponding to the putative ligand binding domain. These variant sequences share the common exon-intron boundary with NOR-1 mRNA, suggesting that they were generated from a single gene by alternative splicing, with the divergent points conserved between the rat and human. We also examined the promoter activities of the 5'-flanking regions of the two NOR-1 transcripts (NOR-1alpha and NOR-1beta mRNAs) by luciferase gene transfection. We demonstrated that the 5'-flanking region of the previously described NOR-1 gene, which has characteristics of a promoter found in housekeeping genes, showed potent promoter activity although the promoter for NOR-1beta mRNAs could not be determined.
Ohkura
N
N
Institute of Biomedical Science, TERUMO R&D Center, Kanagawa 258-0000, Japan. nohkura@gan2.ncc.go.jp
Ito
M
M
Tsukada
T
T
Sasaki
K
K
Yamaguchi
K
K
Miki
K
K
D017398:Alternative Splicing / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000737:chemistry*; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000737:chemistry*; D009419:Nerve Tissue Proteins / Q000737:chemistry*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear / Q000737:chemistry*; D011987:Receptors, Steroid; D011988:Receptors, Thyroid Hormone; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion / Q000235:genetics; D014162:Transfection / Q000235:genetics
D004268:DNA-Binding Proteins; C490412:NR4A3 protein, human; D009419:Nerve Tissue Proteins; C490411:Nr4a3 protein, mouse; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid; D011988:Receptors, Thyroid Hormone