Primary Structure and Coding Genes of Two Pheromones from the Antarctic Psychrophilic Ciliate, Euplotes focardii

• Published in: Microorganisms (Basel) Vol. 10; no. 6; p. 1089
• Main Authors: Alimenti, Claudio, Candelori, Annalisa, Jiang, Yaohan, Luporini, Pierangelo, Vallesi, Adriana
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 25-05-2022; MDPI
• Subjects: Amino acid sequence; Amino acids; Autocrine signalling; Chromatography; Ciliates; Cloning; Coastal waters; Endemic species; Euplotes; Gene amplification; Genomes; Homology; macronuclear gene structures; Mass spectrometry; Nucleotides; Pheromones; polar microbiology; protein pheromones; Proteins; Scientific imaging; Speciation; water-borne chemical signals; United States > US
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms10061089

In ciliates, diffusible cell type-specific pheromones regulate cell growth and mating phenomena acting competitively in both autocrine and heterologous fashion. In Euplotes species, these signaling molecules are represented by species-specific families of structurally homologous small, disulfide-rich proteins, each specified by one of a series of multiple alleles that are inherited without relationships of dominance at the mat-genetic locus of the germinal micronuclear genome, and expressed as individual gene-sized molecules in the somatic macronuclear genome. Here we report the 85-amino acid sequences and the full-length macronuclear nucleotide coding sequences of two pheromones, designated Ef-1 and Ef-2, isolated from the supernatant of a wild-type strain of a psychrophilic species of Euplotes, E. focardii, endemic to Antarctic coastal waters. An overall comparison of the determined E. focardii pheromone and pheromone-gene structures with their homologs from congeneric species provides an initial picture of how an evolutionary increase in the complexity of these structures accompanies Euplotes speciation.