title: Targeting of G alpha i2 to the Golgi by alternative spliced carboxyl-terminal region.
abstract: Heterotrimeric guanosine triphosphate (GTP)-binding proteins (G proteins) may participate in membrane traffic events. A complementary DNA (cDNA) was isolated from a mouse pituitary cDNA library that corresponded to an alternatively spliced form of the gene encoding the G protein alpha subunit G alpha i2. The cDNA was identical to that encoding G alpha i2 except that the region encoding for the carboxyl-terminal 24 amino acids was replaced by a longer region encoding 35 amino acids that have no sequence similarity with G alpha i2 or other members of the G protein family. This alternative spliced product and the corresponding protein (sGi2) were present in several tissues. Specific antibodies revealed that sGi2 was localized in the Golgi apparatus, suggesting a role in membrane transport. Thus, alternative splicing may generate from a single gene two G protein alpha subunits with differential cellular localization and function.
authors.affiliation: Laboratoire de Génétique Moléculaire des Eucaryotes, CNRS, INSERM U184, Faculté de Médecine, Strasbourg, France.
authors.forename: J P
authors.initials: JP
authors.lastname: Montmayeur
authors.forename: E
authors.initials: E
authors.lastname: Borrelli
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D020756:Coatomer Protein; D018076:DNA, Complementary / Q000235:genetics; D051960:GTP-Binding Protein alpha Subunit, Gi2; D019206:GTP-Binding Protein alpha Subunits, Gi-Go; D019204:GTP-Binding Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006056:Golgi Apparatus / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000032:analysis; D008969:Molecular Sequence Data; D015513:Oncogene Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins
chemical_list: D020756:Coatomer Protein; D018076:DNA, Complementary; D008869:Microtubule-Associated Proteins; D015513:Oncogene Proteins; D011518:Proto-Oncogene Proteins; D019204:GTP-Binding Proteins; D051960:GTP-Binding Protein alpha Subunit, Gi2; D019206:GTP-Binding Protein alpha Subunits, Gi-Go; C498016:Gnai2 protein, mouse