InStem - Institute for Stem Cell Science and Regenerative Medicine, Bangalore, India.
Simons Centre for the Study of Living Machines, National Center for Biological Sciences, Tata Institute for Fundamental Research, Bangalore, India.
Elife. 2020 Sep 2;9:e57609. doi: 10.7554/eLife.57609.
Previously, we found that in glucose-limited colonies, metabolic constraints drive cells into groups exhibiting gluconeogenic or glycolytic states. In that study, threshold amounts of trehalose - a limiting, produced carbon-resource, controls the emergence and self-organization of cells exhibiting the glycolytic state, serving as a carbon source that fuels glycolysis (Varahan et al., 2019). We now discover that the plasticity of use of a non-limiting resource, aspartate, controls both resource production and the emergence of heterogeneous cell states, based on differential metabolic budgeting. In gluconeogenic cells, aspartate is a carbon source for trehalose production, while in glycolytic cells using trehalose for carbon, aspartate is predominantly a nitrogen source for nucleotide synthesis. This metabolic plasticity of aspartate enables carbon-nitrogen budgeting, thereby driving the biochemical self-organization of distinct cell states. Through this organization, cells in each state exhibit true division of labor, providing growth/survival advantages for the whole community.
此前,我们发现,在葡萄糖受限的菌落中,代谢限制将细胞驱动成表现出糖异生或糖酵解状态的群体。在那项研究中,海藻糖(一种限制产生的碳源)的阈值量控制着表现出糖酵解状态的细胞的出现和自组织,作为糖酵解的碳源(Varahan 等人,2019 年)。现在,我们发现,非限制资源天冬氨酸的使用灵活性基于差异代谢预算控制着资源生产和异质细胞状态的出现。在糖异生细胞中,天冬氨酸是海藻糖生产的碳源,而在使用海藻糖作为碳源的糖酵解细胞中,天冬氨酸主要是核苷酸合成的氮源。这种天冬氨酸的代谢灵活性实现了碳氮预算,从而驱动了不同细胞状态的生化自组织。通过这种组织,每个状态的细胞都表现出真正的分工,为整个群落提供生长/生存优势。