Yarrowia lipolytica is a dimorphic fungus used as a model organism to investigate diverse biotechnological and biological processes, such as cell differentiation, heterologous protein production, and bioremediation strategies. However, little is known about the biological processes responsible for cation concentration homeostasis. Metals play pivotal roles in critical biochemical processes, and some are toxic at unbalanced intracellular concentrations. Membrane transport proteins control intracellular cation concentrations. Analysis of the Y. lipolytica genome revealed a characteristic functional domain of the cation efflux protein family, i.e., YALI0F19734g, which encodes YALI0F19734p (a putative Yl-Dmct protein), which is related to divalent metal cation tolerance. We report the in silico analysis of the putative Yl-Dmct protein’s characteristics and the phenotypic response to divalent cations (Ca²⁺, Cu²⁺, Fe²⁺, and Zn²⁺) in the presence of mutant strains, Δdmct and Rdmct, constructed by deletion and reinsertion of the DMCT gene, respectively. The absence of the Yl-Dmct protein induces cellular and growth rate changes, as well as dimorphism differences, when calcium, copper, iron, and zinc are added to the cultured medium. Interestingly, the parental and mutant strains were able to internalize the ions. Our results suggest that the protein encoded by the DMCT gene is involved in cell development and cation homeostasis in Y. lipolytica.

Endosymbiotic interactions in fungi are fundamental to ecological and evolutionary processes; however, despite their potential to elucidate key mechanisms of biological integration, they remain insufficiently explored. This review provides a comprehensive synthesis of the available evidence on these associations across major fungal lineages, encompassing their composition, functional attributes, and breadth across diverse model systems. Additionally, the current state of artificial endosymbiosis is examined, together with its applications in multiple areas of biotechnology, spanning both natural and engineered systems. Finally, a framework of progressive endosymbiosis is proposed to describe the continuum of integration states of endosymbionts within fungal hosts. Together, these insights highlight the central role of fungal endosymbiosis in biological integration and underscore its value as a model for understanding evolutionary transitions and developing innovative biotechnological applications.