Lrp家族转录调控因子的研究进展

Research progress of Lrp family transcriptional regulators

亮氨酸应答调控蛋白(Leucine responsive regulatory protein,Lrp)是原核生物中一类重要的转录调控因子,主要由保守的N端DNA结合结构域和响应配体的C端结构域构成,广泛分布于细菌和古生菌中。除氨基酸外,C末端还能够响应其他一些小分子化合物,通过微调DNA结合结构域的空间分布、蛋白的构象和寡聚体形式将信号转化为应答。Lrp可以作为全局或局部转录调控因子,参与控制微生物氨基酸代谢、菌毛生成、重金属转运、多肽运输、能量代谢等多种重要的生理过程。其还可作为“富足/饥饿”调控蛋白协助微生物适应外界多变的环境。近期发现放线菌中Lrp对抗生素生物合成的分子调控作用具有普适性。从Lrp的分布、结构特征、配体种类及响应方式、调控机制,以及在细菌与古生菌中的生物学功能等方面,进行了全面系统地阐述,以期为深入研究Lrp作用的分子机制提供指导。

Leucine responsive regulatory protein(Lrp)is an important transcriptional regulator in prokaryotes,which is mainly composed of conserved N-terminal DNA binding domain and C-terminal domain responding ligand,and it is widely distributed in bacteria and archaea.The C-terminal can respond to some small molecular compounds besides amino acids,and converts signals into responses by fine-tuning the spatial distribution of DNA binding domains,conformation and oligomerization of protein.Lrp can be a global or local transcription regulator to control amino acid metabolism,pili formation,heavy metal transport,polypeptide transportation,energy metabolism and other important physiological processes in microorganisms.It can also act as a"feast/famine"regulatory protein to assist microorganisms to adapt to the changeable environment.Recently,it has been found that Lrp in Actinomycetes has a universal regulation effect on antibiotic biosynthesis.In this paper,the distribution,structural characteristics,ligand categories and response modes,regulatory mechanisms,and biological functions of Lrp in bacteria and archaea were comprehensively and systematically elaborated in order to provide guidance for further study of the molecular mechanism of Lrp.