Nuclear distribution within the extra-radical fungal structures and during spore production in the arbuscular mycorrhizae fungus Glomus intraradices was examined using an in vitro monoxenic culture system. A di-compartmental monoxenic culture system was modified using a nitrocellulose membrane and a coverglass slip for detailed observations. Nuclear distribution was observed using the fluorescent DNA binding probes SYBR Green I and DAPI. Both septate and non-septate mycelial regions were observed, but cytoplasmic contents were only found within non-septate mycelia. Nuclear fluorescent staining revealed that the non-septate hyphal region contained nuclei only with cytoplasm, and that nuclear distribution was limited by septa. Swollen hyphal bodies were often associated with septate and empty-looking hyphae. Cytoplasmic contents filled the swollen hyphal body from the non-septate hyphal region following removal of the septa. As a consequence, the swollen body developed into a new spore. These observations provide understanding about the distribution of AM fungal nuclei within extra-radical mycelia and during spore formation. The results suggest a mechanism by which the development of a cytoplasm-containing mycelium is controlled by the formation or removal of septa to efficiently maintain and proliferate essential contents. This mechanism may provide a survival strategy to the fungus.

中文翻译：

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根内球囊菌（一种丛枝菌根真菌）根外菌丝体中细胞质和细胞核的分布。


使用体外单细胞培养系统检查了根外真菌结构内的核分布以及丛枝菌根真菌根内球囊霉的孢子产生过程中的核分布。使用硝酸纤维素膜和盖玻片修改双室单细胞培养系统以进行详细观察。使用荧光 DNA 结合探针 SYBR Green I 和 DAPI 观察核分布。观察到隔膜和非隔膜菌丝体区域，但细胞质内容物仅在非隔膜菌丝体中发现。核荧光染色显示，无隔膜菌丝区域仅含有细胞核和细胞质，并且核分布受到隔膜的限制。肿胀的菌丝体通常与有隔膜和看起来空的菌丝有关。去除隔膜后，细胞质内容物从非隔膜菌丝区域填充肿胀的菌丝体。结果，肿胀的身体发育成了新的孢子。这些观察结果有助于了解 AM 真菌核在超自由基菌丝体内和孢子形成过程中的分布。结果表明，通过隔膜的形成或去除来控制含有细胞质的菌丝体的发育，以有效维持和增殖必需内容物。这种机制可能为真菌提供生存策略。