title: Transforming activity of the RL-akt gene, a c-akt gene activated by long terminal repeat insertion in murine leukemia RL(male symbol)1 cells.
abstract: The unique antigen peptide pRL1 on BALB/c radiation-induced leukemia RL(male symbol)1 cells is derived from the normally untranslated 5' region of the mouse c-akt gene. Insertion of an endogenous long terminal repeat into the first coding exon of the gene resulted in the enhanced production of an altered akt protein, RL-akt, and creation of the tumor rejection antigen peptide pRL1. In this study, we constructed an RL-akt-expressing vector to investigate the transforming ability and anti-apoptotic activity of RK-akt in NIH/3T3 cells. RL-akt-expressing clones formed more colonies than did c-akt-expressing clones in soft agar and exhibited increased saturation density, a lower serum requirement for growth, and tumorigenicity on athymic nude mice. Immunoblot analysis of subcellular protein distribution showed that a considerable proportion of RL-akt was distributed in the membrane fraction. Thus, RL-akt expressed in NIH/3T3 cells appeared to behave like the v-akt oncoprotein. Furthermore, the RL-akt gene conferred resistance to the apoptosis induced by the calcium ionophore A23187 and by ultraviolet irradiation of NIH/3T3 cells. These findings indicate that the RL-akt gene is able to transform cells and exerts an anti-apoptotic effect on recipient cells, thereby implicating the gene in leukemogenesis of RL(male symbol)1 cells.
authors.affiliation: Department of Molecular Genetics, Okayama University Medical School, Okayama, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Tanino
authors.forename: M
authors.initials: M
authors.lastname: Matsuo
authors.forename: A
authors.initials: A
authors.lastname: Uenaka
authors.forename: K
authors.initials: K
authors.lastname: Tsukuda
authors.forename: M
authors.initials: M
authors.lastname: Ouchida
authors.forename: E
authors.initials: E
authors.lastname: Nakayama
authors.forename: K
authors.initials: K
authors.lastname: Shimizu
mesh_terms: D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D000001:Calcimycin / Q000494:pharmacology; D002448:Cell Adhesion; D002455:Cell Division; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D002471:Cell Transformation, Neoplastic; D005260:Female; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009374:Neoplasms, Experimental / Q000235:genetics / Q000473:pathology; D010957:Plasmids; D017346:Protein Serine-Threonine Kinases; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D051057:Proto-Oncogene Proteins c-akt; D011519:Proto-Oncogenes; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D014162:Transfection; D014466:Ultraviolet Rays
chemical_list: D011518:Proto-Oncogene Proteins; D011994:Recombinant Proteins; D000001:Calcimycin; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt