真菌中一氧化氮生物合成、降解及功能的研究进展

摘要

Nitric oxide is a highly reactive molecule with dichotomous regulatory roles in numerous physiological and pathological events. It has been recognized as an intra-and inter-cellular signaling molecule in animals, plants and microorganisms. Recent research data indicate that fungi are capable of synthesizing nitric oxide. Appropriate amounts of nitric oxide play important biological roles in fungal cells. However, excessive amounts of nitric oxide will damage cells and evoke apoptosis. Nitric oxide regulates the synthesis of cGMP, an important intracellular secondary messenger molecule, involved in the control of a variety of signal transduction pathways in fungal cells. Nitric oxide regulates the cellular development, morphogenesis, sporulation, spore germination, reproduction and apoptosis in fungi. Nitric oxide affects the physiological function of fungi throughout the life cycle. Although the mechanism of nitric oxide in plants and animals has been widely studied, there are limited reports about nitric oxide in fungi; and further investigation is needed to illustrate the nitric oxide synthesis, degradation pathways and the mechanism of signal transduction in the fungal system.%一氧化氮是一个有较高活性的自由基气体分子,无论在动植物还是微生物中,作为一个细胞内和细胞间的信号传导分子,它在许多的生理和病理过程中都发挥着双向的调节作用.研究发现真菌细胞可以合成一氧化氮,适当浓度的一氧化氮在真菌细胞内发挥多种重要的生物学功能,一旦一氧化氮过量累积,这个自由基分子会对细胞造成伤害,导致细胞凋亡.一氧化氮介导生成的环鸟苷酸(cGMP)作为一种重要的第二信使分子涉及到真菌细胞内多种信号途径的调控,调节了整个真菌类群的生长发育、形态发生、孢子形成和萌发、繁殖和细胞凋亡的过程,影响了真菌整个生命周期的生理活动.到目前为止,尽管一氧化氮在动植物中作用的机制得到了广泛的研究,但一氧化氮在真菌中的研究报道很有限.关于一氧化氮在真菌中的合成和降解途径,一氧化氮介导的信号传导机制的研究还不透彻,它在真菌细胞内的功能和毒理还有待于更深入的研究.