A powerful plant-fungus interaction system utilizing the model organisms Neurospora crassa and Brachypodium distachyon
Description
Fungi, beyond their role as saprophytes, engage in intricate relationships with plants, showcasing diverse connections ranging from mutualistic to pathogenic. Employing two well-established model organisms, the grass Brachypodium distachyon and the ascomycete Neurospora crassa we describe here a novel and reliable endophytic interaction. Although N. crassa has been extensively investigated in laboratory conditions, its ecological characteristics remain largely unknown. In contrast, B. distachyon, a sweet grass closely related to significant crops, demonstrates remarkable ecological flexibility and participates in a variety of fungal interactions, encompassing both mutualistic and harmful associations. Through comprehensive microscopic analysis using electron, fluorescence, and confocal laser scanning microscopy, we discovered a novel endophytic interaction between N. crassa and B. distachyon roots, where fungal hyphae not only thrive in the apoplastic space and vascular bundle but also colonize plant root cells. This consistent connection between the fungus and B. distachyon suggests a natural association of the fungus with Poaceae. This discovery opens new perspectives for understanding the fungal life cycle in nature. Moreover, we present a powerful tool for studying plant-fungus interspecies communication, combining well-established model systems.