Tohoku J. Exp. Med., 2018 January, 244(1)

Review

Nucleophagy in Human Disease: Beyond the Physiological Role

MING ZHOU,¹ HONGWEN JI,² NIAN FU,³ LINXI CHEN⁴ and YONG XIA⁵

¹Department of Hematology, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, China.
²Department of Anesthesiology, Transfusion Medicine, Fuwai Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.
³Department of Gastroenterology, Affiliated Nanhua Hospital, University of South China, Hengyang, China.
⁴Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, China.
⁵Affiliated Hospital of Xiangnan University, Chenzhou, China.

Autophagy is an evolutionarily conserved intracellular strategy for degrading organelles and proteins, and nucleophagy refers to the specific process of removing nuclear components from cells by autophagy, Nucleophagy is essential for cell survival by maintaining normal nuclear structure and functions. On the other hand, excessive nucleophagy may result in degradation of essential nuclear components, while impaired nucleophagy may lead to accumulation of harmful metabolic products in the nucleus. Therefore, dysregulation of nucleophagy is likely involved in the pathological process of certain diseases, including psoriasis, cancer, metabolic disorders and aging-related diseases. Nucleophagy is achieved with the participation of various proteins, including proteins encoded by autophagy-related genes (Atg), such as Atg39 and Atg40, as well as nuclear lamina protein lamin B1 and microtubule-associated protein 1 light chain 3 (LC3). Lamin B1 and LC3 are located in the nucleus. Moreover, there are different autophagy patterns in nucleophagy, such as piecemeal microautophagy, late nucleophagy, and micronuclei. Among them, micronuclei are considered a special form of nucleophagy detected in mammalian cells, referring to chromosomes or chromosome fragments that are enclosed by nuclear membrane. The presence of micronuclei usually indicates genotoxic events or the instability of chromosomes. However, in contrast to the well characterized cytoplasmic autophagy, our knowledge on nucleophagy is limited. Here we overview the potential involvement of nucleophagy in human diseases and then summarize the molecular events in the process of nucleophagy.

keywords —— Atg; emerin; lamin; LC3; nucleophagy

© 2018 Tohoku University Medical Press

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Tohoku J. Exp. Med., 2018, 244, 75-81

Correspondence: Yong Xia, Affiliated Hospital of Xiangnan University, 25 Renming Road, Chenzhou 423000, Hunan Province, China.

e-mail: Aetherwh@163.com