Chhoker Kamaldeep, Hausner Georg, Harris Steven D
Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada.
Department of Microbiology, University of Manitoba, Winnipeg, MB, Canada.
Front Fungal Biol. 2025 Aug 29;6:1621764. doi: 10.3389/ffunb.2025.1621764. eCollection 2025.
Melanin is a dark macromolecule found in organisms ranging from animals to fungi and plants. In fungi, melanin is a secondary metabolite that is not essential per se for growth but does provide various benefits that facilitate adaptation to stressful conditions such as UV light, desiccation, oxygen radicals, and extreme temperatures. The biosynthetic pathways of most types of melanin are known and documented, but the regulation of those pathways is not well understood. In fungi, known pathways for melanin production include those directing the synthesis of 1,8-DHN melanin and L-DOPA melanin, as well as the tyrosine degradation pathway. Genetic studies have identified structural genes and enzymes that play a role in these different melanin biosynthesis pathways. Recent studies have focused on the roles of various transcription factors (TFs) and signaling circuits (e.g., cAMP/PKA and the HOG pathway) in regulating the expression of the biosynthetic pathways. The review will provide insights into what is known about these TFs and regulatory circuits in diverse fungi in an attempt to identify common themes.
黑色素是一种深色大分子，存在于从动物到真菌和植物等各类生物体中。在真菌中，黑色素是一种次生代谢产物，其本身并非生长所必需，但确实能提供各种益处，有助于适应诸如紫外线、干燥、氧自由基和极端温度等应激条件。大多数类型黑色素的生物合成途径已为人所知并记录在案，但这些途径的调控机制尚不清楚。在真菌中，已知的黑色素生成途径包括那些指导1,8 - 二羟基萘（1,8 - DHN）黑色素和L - 多巴黑色素合成的途径，以及酪氨酸降解途径。遗传学研究已经确定了在这些不同黑色素生物合成途径中发挥作用的结构基因和酶。最近的研究集中在各种转录因子（TFs）和信号传导通路（如cAMP/PKA和HOG途径）在调节生物合成途径表达中的作用。本综述将深入探讨关于不同真菌中这些转录因子和调控通路的已知信息，试图找出共同的主题。
