The red macroalga Pyropia yezoensis is an economically important seaweed widely cultured in Asian countries and is a model organism for molecular biological and commercial research. This species is unique in that it utilizes both phycobilisomes and transmembrane light‐harvesting proteins as its antenna system. Here, one of the genes of P. yezoensis (PyLHCI) was selected for introduction into its genome to overexpress PyLHCI. However, the co‐suppression phenomenon occurred. This is the first documentation of co‐suppression in algae, in which it exhibits a different mechanism from that in higher plants. The transformant (T1) was demonstrated to have higher phycobilisomes and lower LHC binding pigments, resulting in a redder color, higher sensitivity to salt stress, smaller in size, and slower growth rate than the wildtype (WT). The photosynthetic performances of T1 and WT showed similar characteristics; however, P700 reduction was slower in T1. Most importantly, T1 could release a high percentage of carpospores in young blades to switch generation during its life cycle, which was rarely seen in WT. The co‐suppression of PyLHCI revealed its key roles in light harvesting, stress resistance, and generation alternation (generation switch from gametophytes to sporophytes, and reproduction from asexual to sexual).

中文翻译：

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yezoensis（Rhodophyta）中的共抑制揭示了PyLHCI在光收集和世代转换中的作用

红巨藻Pyropia yezoensis是一种在亚洲国家广泛养殖的具有经济意义的海藻，是用于分子生物学和商业研究的模型生物。该物种的独特之处在于，它利用藻胆体和跨膜采光蛋白作为其天线系统。在这里，yezoensis的基因之一选择（PyLHCI）导入其基因组以过表达PyLHCI。但是，发生了共抑制现象。这是藻类共抑制的第一个文献，它展现出与高等植物不同的机制。事实证明，与野生型（WT）相比，转化子（T1）具有更高的藻胆体和更低的LHC结合色素，导致颜色变红，对盐胁迫的敏感性更高，尺寸更小，生长速度更慢。T1和WT的光合性能表现出类似的特征; 但是，T1的P700降低速度较慢。最重要的是，T1可能会在其幼年叶片中释放出很高比例的幼芽，从而切换世代，这在WT中很少见。PyLHCI的共抑制显示了其在光收集，抗逆性，