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The colonization of land by plants generated opportunities for the rise of new heterotrophic life forms, including humankind. A unique event underpinned this massive change to earth ecosystems—the advent of eukaryotic green algae. Today, an abundant marine green algal group, the prasinophytes, alongside prasinodermophytes and nonmarine chlorophyte algae, is facilitating insights into plant developments. Genome-level data allow identification of conserved proteins and protein families with extensive modifications, losses, or gains and expansion patterns that connect to niche specialization and diversification. Here, we contextualize attributes according to Viridiplantae evolutionary relationships, starting with orthologous protein families, and then focusing on key elements with marked differentiation, resulting in patchy distributions across green algae and plants. We place attention on peptidoglycan biosynthesis, important for plastid division and walls; phytochrome photosensors that are master regulators in plants; and carbohydrate-active enzymes, essential to all manner of carbohydratebiotransformations. Together with advances in algal model systems, these areas are ripe for discovering molecular roles and innovations within and across plant and algal lineages.
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This content will become publicly available on July 1, 2026
A roadmap to developing unified streptophyte algal model systems
Over the last decade, collaborative efforts in plant evolutionary research have elucidated the phylogenetic relationships in the green plant lineage and provided insights into the emergence of land plants from a group of terrestrial and freshwater streptophyte algae. A foremost finding was that the genetic underpinnings of several key traits emerged much earlier than land plants — they were present in their streptophyte algal pro- genitors. Currently, the field is at a crossroads, transitioning from genomics-informed descriptions of strep- tophyte algae to a functional understanding of molecular mechanisms underlying their unique physiology, as well as to understanding their origin and evolution. Major progress has been made in the development of valuable genomic resources, new tools and new model systems in streptophyte algae. In this review, we high- light community-developed resources to study these closest algal relatives of land plants to gain insights into the evolution of land plant traits.
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- Award ID(s):
- 2129443
- PAR ID:
- 10643500
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Current Biology
- Volume:
- 35
- Issue:
- 14
- ISSN:
- 0960-9822
- Page Range / eLocation ID:
- R725 to R738
- Subject(s) / Keyword(s):
- evolution
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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