De Bidhan Chandra, Cournoyer Jay, Gao Yang-le, Wallace Catherine L, Bram Stanley, Mehta Angad P
Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S Mathews Avenue, Urbana, IL, US.
The Imaging Technology Group, Beckman Institute for Advanced Science & Technology, University of Illinois at Urbana-Champaign, 405 North Mathews Avenue, Urbana, IL, US.
Nat Commun. 2024 Dec 10;15(1):10622. doi: 10.1038/s41467-024-54051-1.
Cyanobacterial photosynthesis (to produce ATP and NADPH) might have played a pivotal role in the endosymbiotic evolution to chloroplast. However, rather than meeting the ATP requirements of the host cell, the modern-day land plant chloroplasts are suggested to utilize photosynthesized ATP predominantly for carbon assimilation. This is further highlighted by the fact that the plastidic ADP/ATP carrier translocases from land plants preferentially import ATP. Here, we investigate the preferences of plastidic ADP/ATP carrier translocases from key lineages of photosynthetic eukaryotes including red algae, glaucophytes, and land plants. Particularly, we observe that the cyanobacterial endosymbionts expressing plastidic ADP/ATP carrier translocases from red algae and glaucophyte are able to export ATP and support ATP dependent endosymbiosis, whereas those expressing ADP/ATP carrier translocases from land plants preferentially import ATP and are unable to support ATP dependent endosymbiosis. These data are consistent with a scenario where the ancestral plastids may have exported ATP to support the bioenergetic functions of the host cell.
蓝藻光合作用（产生ATP和NADPH）可能在向叶绿体的内共生进化中起到了关键作用。然而，现代陆地植物叶绿体并非满足宿主细胞的ATP需求，而是被认为主要将光合作用产生的ATP用于碳同化。陆地植物的质体ADP/ATP载体转运蛋白优先导入ATP这一事实进一步凸显了这一点。在这里，我们研究了光合真核生物关键谱系（包括红藻、灰胞藻和陆地植物）的质体ADP/ATP载体转运蛋白的偏好。特别是，我们观察到，表达来自红藻和灰胞藻的质体ADP/ATP载体转运蛋白的蓝藻内共生体能够输出ATP并支持依赖ATP的内共生，而那些表达来自陆地植物的ADP/ATP载体转运蛋白的蓝藻内共生体则优先导入ATP且无法支持依赖ATP的内共生。这些数据与这样一种情况相符，即祖先质体可能输出ATP以支持宿主细胞的生物能量功能。
