Macroalgae are multicellular, aquatic autotrophs that play vital roles in global climate maintenance and have diverse applications in biotechnology and eco-engineering, which are directly linked to their multicellularity phenotypes. However, their genomic diversity and the evolutionary mechanisms underlying multicellularity in these organisms remain uncharacterized. In this study, we sequenced 110 macroalgal genomes from diverse climates and phyla, and identified key genomic features that distinguish them from their microalgal relatives. Genes for cell adhesion, extracellular matrix formation, cell polarity, transport, and cell differentiation distinguish macroalgae from microalgae across all three major phyla, constituting conserved and unique gene sets supporting multicellular processes. Adhesome genes show phylum- and climate-specific expansions that may facilitate niche adaptation. Collectively, our study reveals genetic determinants of convergent and divergent evolutionary trajectories that have shaped morphological diversity in macroalgae and provides genome-wide frameworks to understand photosynthetic multicellular evolution in aquatic environments.

中文翻译：

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大型藻类深度基因组学阐明了实现水生光合多细胞性的多条途径


大型藻类是多细胞、水生自养生物，在全球气候维持中起着至关重要的作用，并在生物技术和生态工程中有多种应用，这与它们的多细胞表型直接相关。然而，它们的基因组多样性和这些生物体中多细胞性的进化机制仍未得到表征。在这项研究中，我们对来自不同气候和门的 110 个大型藻类基因组进行了测序，并确定了将它们与微藻亲属区分开来的关键基因组特征。细胞粘附、细胞外基质形成、细胞极性、运输和细胞分化的基因在所有三个主要门中区分大型藻类和微藻，构成支持多细胞过程的保守和独特基因集。贴红体基因显示出门和气候特异性的扩展，这可能促进生态位适应。总的来说，我们的研究揭示了影响大型藻类形态多样性的趋同和发散进化轨迹的遗传决定因素，并为理解水生环境中的光合多细胞进化提供了全基因组框架。