Activated by the Autocrine Pheromone-Signaling Loop in the

• Main Authors: Annalisa C, Pierangelo Luporini, Claudio Alimenti, Adriana Vallesi
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2013
• Subjects: protein kinase; signal transduction; gene structure and expression; translational frameshifting; polar ciliatesInt. J. Mol. Sci. 2013; 14 7458; Antarctic; Arctic; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.297.8691; http://www.mdpi.com/1422-0067/14/4/7457/pdf/

Abstract: 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.