Department of Genetics, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA.
mBio. 2013 Mar 26;4(2):e00142-13. doi: 10.1128/mBio.00142-13.
Light is a pervasive environmental factor that regulates development, stress resistance, and even virulence in numerous fungal species. Though much research has focused on signaling pathways in Aspergillus fumigatus, an understanding of how this pathogen responds to light is lacking. In this report, we demonstrate that the fungus does indeed respond to both blue and red portions of the visible spectrum. Included in the A. fumigatus light response is a reduction in conidial germination rates, increased hyphal pigmentation, enhanced resistance to acute ultraviolet and oxidative stresses, and an increased susceptibility to cell wall perturbation. By performing gene deletion analyses, we have found that the predicted blue light receptor LreA and red light receptor FphA play unique and overlapping roles in regulating the described photoresponsive behaviors of A. fumigatus. However, our data also indicate that the photobiology of this fungus is complex and likely involves input from additional photosensory pathways beyond those analyzed here. Finally, whole-genome microarray analysis has revealed that A. fumigatus broadly regulates a variety of metabolic genes in response to light, including those involved in respiration, amino acid metabolism, and metal homeostasis. Together, these data demonstrate the importance of the photic environment on the physiology of A. fumigatus and provide a basis for future studies into this unexplored area of its biology.
光是一种普遍存在的环境因素，它可以调节许多真菌物种的发育、抗逆性，甚至毒力。尽管许多研究都集中在烟曲霉的信号通路，但对这种病原体如何对光做出反应的了解还很缺乏。在本报告中，我们证明了真菌确实对可见光的蓝色和红色部分都有反应。烟曲霉的光反应包括降低分生孢子的萌发率、增加菌丝体色素沉着、增强对急性紫外线和氧化应激的抗性，以及增加对细胞壁扰动的敏感性。通过进行基因缺失分析，我们发现预测的蓝光受体 LreA 和红光受体 FphA 在调节烟曲霉描述的光响应行为中发挥独特且重叠的作用。然而，我们的数据还表明，这种真菌的光生物学很复杂，可能涉及到除了这里分析的那些以外的其他光感觉途径的输入。最后，全基因组微阵列分析表明，烟曲霉广泛调节多种代谢基因对光的反应，包括参与呼吸、氨基酸代谢和金属稳态的基因。总之，这些数据表明光环境对烟曲霉生理学的重要性，并为未来对这一未被探索的生物学领域的研究提供了基础。
