EMR1, an unusual member in the family of hormone receptors with seven transmembrane segments

• Published in: Genomics (San Diego, Calif.) Calif.), 1995-03, Vol.26 (2), p.334-344
• Main Authors: Baud, Véronique, Chissoe, Stephanie L., Viegas-Péquignot, Evani, Diriong, Sylvie, Van Cong N'guyen, Roe, Bruce A., Lipinski, Marc
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Biological and medical sciences; Chromosomes, Human, Pair 19; Consensus Sequence; Cricetinae; DNA, Complementary - genetics; Epidermal Growth Factor - chemistry; Fundamental and applied biological sciences. Psychology; Genes; Genes. Genome; Humans; Hybrid Cells; Membrane Glycoproteins - chemistry; Membrane Glycoproteins - genetics; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Mucins - chemistry; Mucins - genetics; Multigene Family; Protein Conformation; Receptors, Cell Surface - chemistry; Receptors, G-Protein-Coupled; RNA, Heterogeneous Nuclear - genetics; Sequence Alignment; Sequence Homology, Amino Acid
• ISSN: 0888-7543; 1089-8646
• DOI: 10.1016/0888-7543(95)80218-B

Proteins with seven transmembrane segments (7TM) define a superfamily of receptors (7TM receptors) sharing the same topology: an extracellular N-terminus, three extramembranous loops on either side of the plasma membrane, and a cytoplasmic C-terminal tail. Upon ligand binding, cytoplasmic portions of the activated receptor interact with heterotrimeric G-coupled proteins to induce various second messengers. A small group, recently recognized on the basis of homologous primary amino acid sequences, comprises receptors to hormones of the secretin/vasoactive intestinal peptide/glucagon family, parathyroid hormone and parathyroid hormone-related peptides, growth hormone-releasing factor, corticotropin-releasing factor, and calcitonin. A cDNA, extracted from a neuroectodermal cDNA library, was predicted to encode a new 886-amino-acid protein with three distinct domains. The C-terminal third contains the seven hydrophobic segments and characteristic residues that allow the protein to be readily aligned with the various hormone receptors in the family. Six egf-like modules, at the N-terminus of the predicted mature protein, are separated from the transmembrane segments by a serine/threonine-rich domain, a feature reminiscent of mucin-like, single-span, integral membrane glycoproteins with adhesive properties. Because of its unique characteristics, this putative egf module-containing, mucin-like hormone receptor has been named EMR1. Southern analysis of a panel of somatic cell hybrids and fluorescence in situ hybridization have assigned the EMR1 gene to human chromosome 19p13.3.