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Title: Organ Evolution: Emergence of Multicellular Function
Instances of multicellularity across the tree of life have fostered the evolution of complex organs composed of distinct cell types that cooperate, producing emergent biological functions. How organs originate is a fundamental evolutionary problem that has eluded deep mechanistic and conceptual understanding. Here I propose a cell- to organ-level transitions framework, whereby cooperative division of labor originates and becomes entrenched between cell types through a process of functional niche creation, cell-type subfunctionalization, and irreversible ratcheting of cell interdependencies. Comprehending this transition hinges on explaining how these processes unfold molecularly in evolving populations. Recent single-cell transcriptomic studies and analyses of terminal fate specification indicate that cellular functions are conferred by modular gene expression programs. These discrete components of functional variation may be deployed or combined within cells to introduce new properties into multicellular niches, or partitioned across cells to establish division of labor. Tracing gene expression program evolution at the level of single cells in populations may reveal transitions toward organ complexity.  more » « less
Award ID(s):
2047472
PAR ID:
10559574
Author(s) / Creator(s):
Publisher / Repository:
Annual Reviews
Date Published:
Journal Name:
Annual Review of Cell and Developmental Biology
Volume:
40
Issue:
1
ISSN:
1081-0706
Page Range / eLocation ID:
51 to 74
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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