West Christopher M, Blader Ira J
Department of Biochemistry & Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, 975 NE 10th St., BRC 417, Oklahoma City, OK 73104, USA.
Department of Microbiology and Immunology, University at Buffalo School of Medicine, 347 Biomedical Research Building, 3435 Main Street, Buffalo, NY 14214, USA.
Curr Opin Microbiol. 2015 Aug;26:41-7. doi: 10.1016/j.mib.2015.04.006. Epub 2015 May 17.
Cells must know the local levels of available oxygen and either adapt accordingly or relocate to more favorable environments. Prolyl 4-hydroxylases (P4Hs) are emerging as universal cellular oxygen sensors. In animals, these oxygen sensors respond to decreased oxygen availability by up-regulating hypoxia-inducible transcription factors. In protozoa, the P4Hs appear to activate E3-SCF ubiquitin ligase complexes via a glycosylation-dependent mechanism, potentially to turn over their proteomes. Intracellular parasites are impacted by both types of oxygen-sensing pathways. Since parasites are exposed to diverse oxygen tensions during their life cycles, this review identifies emerging oxygen-sensing mechanisms and discusses how these mechanisms probably contribute to the regulation of unicellular eukaryotes.
细胞必须了解局部可利用氧气的水平,并据此进行适应或迁移到更适宜的环境中。脯氨酰4-羟化酶(P4Hs)正逐渐成为通用的细胞氧传感器。在动物中,这些氧传感器通过上调缺氧诱导转录因子来应对氧气供应减少的情况。在原生动物中,P4Hs似乎通过一种糖基化依赖机制激活E3-SCF泛素连接酶复合物,这可能是为了更新它们的蛋白质组。细胞内寄生虫会受到这两种氧感应途径的影响。由于寄生虫在其生命周期中会暴露于不同的氧张力下,本综述确定了新出现的氧感应机制,并讨论了这些机制可能如何对单细胞真核生物的调节产生影响。