Tyrosine phosphorylation in Tetrahymena thermophila during intercellular communication

Emerging evidence suggests that tyrosine phosphorylation signaling is present in unicellular organisms. There is also emerging evidence suggesting the presence of tyrosine phosphorylation in the unicellular ciliate protozoan, Tetrahymena thermophila. T. thermophila shares a high number of orthologs with humans. Understanding tyrosine phosphorylation in unicells could help us understand how this pathway works in multicells. In this investigation, tyrosine phosphorylation signaling is investigated in T thermophila during starvation and conjugation as it could play a role in mating in this organism. This was done by applying Western blot, indirect immunofluorescence microscopy, bioinformatics, and gene knockout. The immunodetection methods combined with anti-phosphotyrosine antibody suggest the presence of tyrosine phosphorylation in starved and conjugating cells. The bioinformatic data also show proteins that could be tyrosine phosphorylated during starvation and conjugation. In addition, for one of these proteins, its gene was prepared for investigation by knocking out its coding region and replacing it with a neo4 cassette to investigate its role and possible relevance to tyrosine phosphorylation signaling. These data combined with previous work suggest that there is tyrosine phosphorylation signaling in T. thermophila that occurs during mating and preparation for mating.