Characterization and expression of the gene encoding En-MAPK1, an intestinal cell kinase (ICK)-like kinase activated by the autocrine pheromone-signaling loop in the Polar Ciliate, Euplotes nobilii

• Published in: International journal of molecular sciences Vol. 14; no. 4; pp. 7457 - 7467
• Main Authors: Candelori, Annalisa, Luporini, Pierangelo, Alimenti, Claudio, Vallesi, Adriana
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 03-04-2013; Molecular Diversity Preservation International (MDPI)
• Subjects: Amino Acid Sequence; Amino acids; Antibodies; Autocrine Communication - physiology; Cell cycle; Cell growth; Cloning, Molecular; Euplotes - enzymology; Euplotes - genetics; Gene Expression Regulation, Enzymologic - physiology; gene structure and expression; Genomes; Growth factors; Humans; Kinases; Male; MAP Kinase Signaling System - physiology; Mitogen-Activated Protein Kinase 1 - biosynthesis; Mitogen-Activated Protein Kinase 1 - genetics; Molecular Sequence Data; Pheromones; Pheromones - secretion; Phosphatase; Phosphorylation; polar ciliates; protein kinase; Proteins; Protozoan Proteins - biosynthesis; Protozoan Proteins - genetics; Signal transduction; translational frameshifting; Arctic region
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms14047457

In the protozoan ciliate Euplotes, a transduction pathway resulting in a mitogenic cell growth response is activated by autocrine receptor binding of cell type-specific, water-borne signaling protein pheromones. In Euplotes raikovi, a marine species of temperate waters, this transduction pathway was previously shown to involve the phosphorylation of a nuclear protein kinase structurally similar to the intestinal-cell and male germ cell-associated kinases described in mammals. In E. nobilii, which is phylogenetically closely related to E. raikovi but inhabits Antarctic and Arctic waters, we have now characterized a gene encoding a structurally homologous kinase. The expression of this gene requires +1 translational frameshifting and a process of intron splicing for the production of the active protein, designated En-MAPK1, which contains amino acid substitutions of potential significance for cold-adaptation.