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

• Published in: Microorganisms
• Main Authors: Alimenti C., Candelori C., Jiang Y., Luporini P., Vallesi A.
• Other Authors: Alimenti, C., Candelori, C., Jiang, Y., Luporini, P., Vallesi, A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: Antarctic; The Antarctic; Antarc*
• Online Access: http://hdl.handle.net/11581/463166; https://doi.org/10.3390/microorganisms10061089; https://www.mdpi.com/2076-2607/10/6/1089

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.