A computational model capable of predicting whether or not organisms are phagocytotic has been developed. This model is not only useful to study the evolution of complex life it also has utility in DNA sequencing projects that involve multiple unknown microbial species, according to researchers from the American Museum of Natural History.
The model and the researchers' findings related to Asgard archaea microorganisms were published earlier this week in a Nature Ecology & Evolution paper.
"Phagocytosis is a major mechanism of nutritional uptake in many single-celled organisms, and it's vital to immune defenses in a number of living things, including humans," said co-author Eunsoo Kim, an associate curator in the American Museum of Natural History's division of invertebrate zoology. "But lesser known is the idea that phagocytosis dates back some 2 to 3 billion years and played a role in those symbiotic associations that likely started the cascading evolution toward the more diverse and complex life we see on the planet today. Our research provides some hints as to how phagocytosis first arose."
"There's no single set of genes that are strongly predictive of phagocytosis because it's a very complicated process that can involve more than 1,000 genes, and those genes can greatly vary from species to species," said lead author John Burns, a research scientist in the Museum's Sackler Institute for Comparative Genomics." But as we started looking at the genomes of more and more eukaryotes, a genetic pattern emerged, and it exists across diversity, even though it's slightly different in each species. That pattern is the core of our model, and we can use it to very quickly and efficiently predict which cells are likely to be 'eaters' and which are not."
It can be hard to determine if eukaryotes are capable of phagocytosis simply by watching them under a microscope so this new model can help microbiologists make a quick assessment. It may also be valuable for use in large DNA sequencing projects that involve multiple unknown microbial species.
Image: Phagocytosis, or cell eating, is a key feature of eukaryotic cells that is not present in the archaea or bacteria. Current genomic data provides the key to this and other complex processes with hints at how they may have originated. Image courtesy of AMNH/S. Thurston.