The evolution of multicellularity is a large and complex topic, considered a major transition in the history of life.
To be defined as multicellular, an organism must meet two essential criteria: intercellular communication leading to coordinated action, and cell-cell adhesion. These traits, in more complex bodies, become more elaborate and combine with programmed cell death.
Phytoplankton populations often display the characteristics of a multicellular-like community rather than a random collection of individuals. They are thought of as “an evolutionary snapshot toward multicellularity”; an intermediate state between single cells and aggregates of physically attached cells that communicate and cooperate.
Furthermore, some unicellular populations show changes across their life cycle. At some level, these changes may be interpreted as developmental, although they do not involve the differentiation and integration of multiple cell types, sophisticated communication among cells, or cell death. In this sense, the evolution of complex bodies, which requires all these characteristics, was the evolution of development itself.
Which molecular mechanisms supported the evolution of multicellularity? To answer this question, phylogenetically relevant groups with facultative multicellularity have been studied. Among these, in green algae, fungi, slime molds, and choanoflagellates, genes encoding extracellular matrix proteins and cytokinesis regulators have been found to be either necessary or sufficient for their multicellularity. This suggests that the initial evolution of multicellularity on different branches of the tree of life converged from similar mechanisms.
Several observations in key phytoplankton groups (such as diatoms) denote phenotypic heterogeneity: enzymatic activities, structural features, biomineralization processes, biosynthesis of secreted molecules, as well as motility and sexual reproduction. If interpreted in a multicellular context, this division of labor could promote the quick adaptation to environmental changes.
Hence, the study of unicellular species could represent a valuable way to understand the molecular mechanisms at the basis of multicellularity.
To address the multicellularity evolution question, the following themes should be tackled.
How do unicellular organisms:
- share information and give rise to coordinated activity?
- regulate their growth and cell cycle?
- adhere to each other?
The exploration of this topic is prompted by the advent of single cell sequencing technologies to study cell-to-cell variability on a genomic scale, but also through all the other -omics tools and the traditional biochemistry, and cell and molecular biology approaches.
The application of studies both in wet lab and in the environment are encouraged. Moreover, investigations carried on simple forms of multicellularity such as filaments, clusters, balls, or sheets of cells will be considered, as well as those on early branching metazoan development (e.g., sponges, ctenophores, and placozoans).
The integration of all these lines of exploration will shed light on the transition from the microbial world to the vegetable and animal kingdom.
Primary data papers, methods, perspectives, and reviews will be considered.
The evolution of multicellularity is a large and complex topic, considered a major transition in the history of life.
To be defined as multicellular, an organism must meet two essential criteria: intercellular communication leading to coordinated action, and cell-cell adhesion. These traits, in more complex bodies, become more elaborate and combine with programmed cell death.
Phytoplankton populations often display the characteristics of a multicellular-like community rather than a random collection of individuals. They are thought of as “an evolutionary snapshot toward multicellularity”; an intermediate state between single cells and aggregates of physically attached cells that communicate and cooperate.
Furthermore, some unicellular populations show changes across their life cycle. At some level, these changes may be interpreted as developmental, although they do not involve the differentiation and integration of multiple cell types, sophisticated communication among cells, or cell death. In this sense, the evolution of complex bodies, which requires all these characteristics, was the evolution of development itself.
Which molecular mechanisms supported the evolution of multicellularity? To answer this question, phylogenetically relevant groups with facultative multicellularity have been studied. Among these, in green algae, fungi, slime molds, and choanoflagellates, genes encoding extracellular matrix proteins and cytokinesis regulators have been found to be either necessary or sufficient for their multicellularity. This suggests that the initial evolution of multicellularity on different branches of the tree of life converged from similar mechanisms.
Several observations in key phytoplankton groups (such as diatoms) denote phenotypic heterogeneity: enzymatic activities, structural features, biomineralization processes, biosynthesis of secreted molecules, as well as motility and sexual reproduction. If interpreted in a multicellular context, this division of labor could promote the quick adaptation to environmental changes.
Hence, the study of unicellular species could represent a valuable way to understand the molecular mechanisms at the basis of multicellularity.
To address the multicellularity evolution question, the following themes should be tackled.
How do unicellular organisms:
- share information and give rise to coordinated activity?
- regulate their growth and cell cycle?
- adhere to each other?
The exploration of this topic is prompted by the advent of single cell sequencing technologies to study cell-to-cell variability on a genomic scale, but also through all the other -omics tools and the traditional biochemistry, and cell and molecular biology approaches.
The application of studies both in wet lab and in the environment are encouraged. Moreover, investigations carried on simple forms of multicellularity such as filaments, clusters, balls, or sheets of cells will be considered, as well as those on early branching metazoan development (e.g., sponges, ctenophores, and placozoans).
The integration of all these lines of exploration will shed light on the transition from the microbial world to the vegetable and animal kingdom.
Primary data papers, methods, perspectives, and reviews will be considered.
