The essential role of the cellular prion protein (PrP^C) in prion disorders such as Creutzfeldt–Jakob disease is well documented. Moreover, evidence is accumulating that PrP^C may act as a receptor for protein aggregates and transduce neurotoxic signals in more common neurodegenerative disorders, such as Alzheimer’s disease. Although the pathological roles of PrP^C have been thoroughly characterized, a general consensus on its physiological function within the brain has not yet been established. Knockout studies in various organisms, ranging from zebrafish to mice, have implicated PrP^C in a diverse range of nervous system-related activities that include a key role in the maintenance of peripheral nerve myelination as well as a general ability to protect against neurotoxic stimuli. Thus, the function of PrP^C may be multifaceted, with different cell types taking advantage of unique aspects of its biology. Deciphering the cellular function(s) of PrP^C and the consequences of its absence is not simply an academic curiosity, since lowering PrP^C levels in the brain is predicted to be a powerful therapeutic strategy for the treatment of prion disease. In this review, we outline the various approaches that have been employed in an effort to uncover the physiological and pathological functions of PrP^C. While these studies have revealed important clues about the biology of the prion protein, the precise reason for PrP^C’s existence remains enigmatic.

细胞病毒蛋白（PrP ^C）在诸如Creutzfeldt–Jakob病等病毒疾病中的重要作用已得到充分证明。此外，越来越多的证据表明，PrP ^C可能在更常见的神经退行性疾病（例如阿尔茨海默氏病）中充当蛋白质聚集体的受体并转导神经毒性信号。尽管已对PrP ^C的病理作用进行了充分的表征，但尚未确定其在大脑中的生理功能的一般共识。从斑马鱼到小鼠的各种生物的敲除研究都涉及到PrP ^C与神经系统相关的各种活动，包括在维持周围神经的髓鞘形成中起关键作用，以及抵抗神经毒性刺激的一般能力。因此，PrP ^C的功能可能是多方面的，利用其生物学独特方面的不同细胞类型。破解PrP ^C的细胞功能及其缺乏的后果并非只是出于学术上的好奇心，因为降低大脑中的PrP ^C水平被认为是治疗病毒疾病的有效策略。在这篇综述中，我们概述了试图揭示PrP ^C的生理和病理功能的各种方法。。尽管这些研究揭示了有关the病毒蛋白质生物学的重要线索，但PrP ^C存在的确切原因仍然是个谜。