Physiological functions and clinical implications of the N-end rule pathway

Abstract

The N-end rule pathway is a unique branch of the ubiquitin-proteasome system in which the determination of a protein’s half-life is dependent on its N-terminal residue. The N-terminal residue serves as the degradation signal of a protein and thus called N-degron. N-degron can be recognized and modifed by several steps of post-translational modifications, such as oxidation, deamination, arginylation or acetylation, it then polyubiquitinated by the N-recognin for degradation. The molecular basis of the N-end rule pathway has been elucidated and its physiological functions have been revealed in the past 30 years. This pathway is involved in several biological aspects, including transcription, differentiation, chromosomal segregation, genome stability, apoptosis, mitochondrial quality control, cardiovascular development, neurogenesis, carcinogenesis, and spermatogenesis. Disturbance of this pathway often causes the failure of these processes, resulting in some human diseases. This review summarized the physiological functions of the N-end rule pathway, introduced the related biological processes and diseases, with an emphasis on the inner link between this pathway and certain symptoms.

Keywords

N-end rule pathway / Ate1 / cardiovascular development / neurogenesis / spermatogenesis / neurodegenerative disorders / Johanson–Blizzard syndrome

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 31471277 and 91519317).

Compliance with ethics guidelines

Yujiao Liu, Chao Liu, Wen Dong, and Wei Li declare that they have no financial conflicts of interest. This manuscript is a review article and does not involve a research protocol requiring approval by a relevant institutional review board or ethics committee.

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2016 Higher Education Press and Springer-Verlag Berlin Heidelberg