Jun 17, 2025 05:20 PM
From single cells to complex creatures: New study points to origins of animal multicellularity
https://www.eurekalert.org/news-releases/1087193
INTRO: Animals, from worms and sponges to jellyfish and whales, contain anywhere from a few thousand to tens of trillions of nearly genetically identical cells. Depending on the organism, these cells arrange themselves into a variety of tissues and organs, such as a gut, muscles, and sensory systems. While not all animals have each of these tissues, they do all have one tissue, the germline, that produces sperm or eggs to propagate the species.
Scientists don’t completely understand how this kind of multicellularity evolved in animals. Cell-cell adhesion, or the ability for individual cells to stick to each other, certainly plays a role, but scientists already know that the proteins that serve these functions evolved in single-celled organisms, well before animal life emerged.
Now, research from the University of Chicago provides a new view into key innovations that allowed modern, multicellular animals to emerge. By analyzing the proteins predicted from the genomes of many animals (and close relatives to the animal kingdom), researchers found that animals evolved a more sophisticated mechanism for cell division that also contributes to developing multicellular tissues and the germline.
“This work strongly suggests that one of the early steps in the evolution of animals was the formation of the germline through the ability of cells to stay connected by incomplete cytokinesis,” said Michael Glotzer, PhD, Professor of Molecular Genetics and Cell Biology at UChicago and author of the new study. “The evolution of these three proteins allowed both multicellularity and the ability to form a germline: two of the key features of animals.” (MORE - details, no ads)
https://www.eurekalert.org/news-releases/1087193
INTRO: Animals, from worms and sponges to jellyfish and whales, contain anywhere from a few thousand to tens of trillions of nearly genetically identical cells. Depending on the organism, these cells arrange themselves into a variety of tissues and organs, such as a gut, muscles, and sensory systems. While not all animals have each of these tissues, they do all have one tissue, the germline, that produces sperm or eggs to propagate the species.
Scientists don’t completely understand how this kind of multicellularity evolved in animals. Cell-cell adhesion, or the ability for individual cells to stick to each other, certainly plays a role, but scientists already know that the proteins that serve these functions evolved in single-celled organisms, well before animal life emerged.
Now, research from the University of Chicago provides a new view into key innovations that allowed modern, multicellular animals to emerge. By analyzing the proteins predicted from the genomes of many animals (and close relatives to the animal kingdom), researchers found that animals evolved a more sophisticated mechanism for cell division that also contributes to developing multicellular tissues and the germline.
“This work strongly suggests that one of the early steps in the evolution of animals was the formation of the germline through the ability of cells to stay connected by incomplete cytokinesis,” said Michael Glotzer, PhD, Professor of Molecular Genetics and Cell Biology at UChicago and author of the new study. “The evolution of these three proteins allowed both multicellularity and the ability to form a germline: two of the key features of animals.” (MORE - details, no ads)
