CELL ADHESION MECHANISMS: A WINDOW INTO THE EVOLUTION OF MULTICELLULARITY

Abstract

Background: The study explores how single-celled organisms evolved into multicellular, focusing on the mechanisms of cell adhesion as a determining factor in this transition. Volvocaceae algae have evolved to form multicellular colonies, where cells communicate via cytoplasmic bridges. In contrast, multicellular animals have evolved complex junctions, such as gap-like junctions and desmosomes, that allow for communication and adhesion between cells. Cell adhesion is crucial for the formation of multicellular structures, ensuring cohesion and communication between cells.

Methodology: A literature review was carried out between 2003 and 2024, using databases such as Web of Science, Zoological Record, and Google Scholar. Search terms included "Cell Adhesion," "Intercellular Junctions," "Tissues," and "Green Algae." Only peer-reviewed articles comparing the evolution of the mechanisms of communication between cells of Volvocaceae algae and multicellular animals were included, excluding narrative and editorial studies.

Results: The results indicate that Volvocaceae animals and algae followed different evolutionary trajectories in the development of cell junctions. Animals have evolved complex junctions, such as desmosomes and gap-like junctions, which are essential for cell communication and adhesion. In comparison, the Volvocaceae algae maintained simpler adhesion mechanisms, using cytoplasmic bridges and connections with the extracellular matrix to maintain cell cohesion in the colonies, without the sophistication of the junctions observed in the animals.

Conclusion: The comparative analysis reveals that, although both the animals and the Volvocaceae algae evolved for multicellularity, the animals developed more advanced cell junctions, while the algae opted for simpler communication and adhesion strategies. This illustrates the diversity of evolutionary pathways that underpin multicellularity in different groups.