p62/SQSTM1-droplet serves as a platform for autophagosome formation and anti-oxidative stress response

Kageyama, Shun; Guðmundsson, Sigurður; Sou, Yu‐shin; Ichimura, Yoshinobu; Tamura, Naoki; Kazuno, Saiko; Ueno, Takashi; Miura, Yoshiki; Noshiro, Daisuke; Abe, Manabu; Mizushima, Tsunehiro; Miura, Nobuaki; Okuda, Shujiro; Motohashi, Hozumi; Lee, Jin A; Sakimura, Kenji; Ohe, Tomoyuki; Noda, Nobuo N.; Waguri, Satoshi; Eskelinen, Eeva‐Liisa; Komatsu, Masaaki

doi:10.1038/s41467-020-20185-1

Cited by 165 publications

(170 citation statements)

References 69 publications

(55 reference statements)

Supporting

Mentioning

158

Contrasting

Order By: Relevance

“…Mutations in the p62 gene are strongly associated with Paget's disease of the bone (19), murine myeloid leukemia progression (20), neurodegenerative disease (21), obesity (22), vascular senescence (23), aging pathologies and cancer (24,25). p62 consists of 440 amino acids covering more than 10 domains and binding sites; hence, it is a key center of regulating multiple activities of cells, such as insulin signaling, energy balance, adipogenesis, brown adipose tissue (BAT) thermogenesis, inflammation, oxidative stress, apoptosis, etc (26)(27)(28)(29)(30).…”

Section: Introductionmentioning

confidence: 99%

SQSTM1/p62 Promotes Cell Growth and Triggers Autophagy in Papillary Thyroid Cancer by Regulating the AKT/AMPK/mTOR Signaling Pathway

Liu

et al. 2021

Front. Oncol.

View full text Add to dashboard Cite

BackgroundThyroid cancer is one of the most common endocrine malignancies worldwide, and papillary thyroid cancer (PTC) is the most common pathologic type of thyroid cancer. SQSTM1/p62 activity mediates different biological functions. This study aimed to investigate the effect of SQSTM1/p62, a multifunctional receptor, on biological function and autophagy characteristics in the human PTC cell line TPC-1.MethodsA total of 105 primary PTC samples and matched adjacent normal thyroid tissue samples were obtained to evaluate the expression of p62 in clinical patients. A similar p62 expression pattern was found in PTC cell lines and normal human thyroid follicular epithelial cells. To evaluate the effect of SQSTM1/p62 on TPC-1 cells, we constructed the p62 knockout cell line p62-KO-TPC-1. Cell proliferation, cell cycle, and cell apoptosis were analyzed by colony formation tests, Cell Counting Kit-8 (CCK-8) assays and flow cytometry in vitro. TPC-1 and p62-KO-TPC-1 human PTC cell lines in the logarithmic growth phase were subcutaneously implanted into BALB/c nude mice to verify their proliferation effect in vivo. Furthermore, western blotting and immunohistochemistry (IHC) were used to detect the expression of AKT/AMPK/mTOR signaling pathway-related proteins.ResultsOverall, p62 expression was higher in tumor tissues than in normal tissues in 73 of 105 PTC patients (69.5%). The expression level of p62 in the PTC cell line was higher than that in the normal thyroid cell line. Our data indicated that in vitro, p62 deficiency could decrease the number of colonies, inhibit cell growth and the cell cycle, and induce apoptosis. Tumor xenograft experiments in BALB/c nude mice corroborated these findings. Moreover, the molecular mechanism was explored by western blotting, and we found that the AMPK/AKT/mTOR pathway was involved.ConclusionsThe results indicate that p62 might mediate cell autophagy and apoptosis in TPC-1 cells via the AMPK/AKT/mTOR pathway and could be used as a potential therapeutic approach for PTC.

show abstract

Section: Introductionmentioning

confidence: 99%

SQSTM1/p62 Promotes Cell Growth and Triggers Autophagy in Papillary Thyroid Cancer by Regulating the AKT/AMPK/mTOR Signaling Pathway

Liu

et al. 2021

Front. Oncol.

View full text Add to dashboard Cite

show abstract

“…Because Keap1 is ubiquitinated in a p62-dependent manner, it is speculated that HN does not degrade Keap1 by promoting autophagy. Whether HN activates Nrf2 by affecting the conformation of Keap1 needs further study ( 74 , 75 ) ( Figure 2 ).…”

Section: Hn and Oxidative Stressmentioning

confidence: 99%

Protective Mechanism of Humanin Against Oxidative Stress in Aging-Related Cardiovascular Diseases

2021

View full text Add to dashboard Cite

Physiological reactive oxygen species (ROS) are important regulators of intercellular signal transduction. Oxidative and antioxidation systems maintain a dynamic balance under physiological conditions. Increases in ROS levels destroy the dynamic balance, leading to oxidative stress damage. Oxidative stress is involved in the pathogenesis of aging-related cardiovascular diseases (ACVD), such as atherosclerosis, myocardial infarction, and heart failure, by contributing to apoptosis, hypertrophy, and fibrosis. Oxidative phosphorylation in mitochondria is the main source of ROS. Increasing evidence demonstrates the relationship between ACVD and humanin (HN), an endogenous peptide encoded by mitochondrial DNA. HN protects cardiomyocytes, endothelial cells, and fibroblasts from oxidative stress, highlighting its protective role in atherosclerosis, ischemia–reperfusion injury, and heart failure. Herein, we reviewed the signaling pathways associated with the HN effects on redox signals, including Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2), chaperone-mediated autophagy (CMA), c-jun NH2 terminal kinase (JNK)/p38 mitogen-activated protein kinase (p38 MAPK), adenosine monophosphate-activated protein kinase (AMPK), and phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)-Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3). Furthermore, we discussed the relationship among HN, redox signaling pathways, and ACVD. Finally, we propose that HN may be a candidate drug for ACVD.

show abstract

“…Recent growing lines of evidence shed light on unique feature of p62, phaseseparation of p62 dependent on the presence of ubiquitin chains (17). The phase-separated p62 droplets allow the exchange of their components, including ubiquitin, LC3 and Keap1, with the surrounding environment (17)(18)(19)(20). Inside a liquid-like droplet, molecules would be predicted to maintain their conformation and activity.…”

Section: Introductionmentioning

confidence: 99%

“…Finally, cluster formation is rendered more efficient by the presence of NBR1, another autophagic adaptor that cooperates with p62 in cells (18,19). Thus, p62-droplets and/or gels are not simple substrates for autophagy but serve as platforms for both autophagosome formation and anti-oxidative stress (20,21).…”

Section: Introductionmentioning

confidence: 99%

“…Inside a liquid-like droplet, molecules would be predicted to maintain their conformation and activity. Consequently, the droplets could also serve as nodes, from which signaling cascades could be activated in the context of selective autophagy and the Keap1-Nrf2 pathway (20,21). p62 clustering appears to require multiple ubiquitin chains of at least three ubiquitin moieties.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Droplets of amyotrophic lateral sclerosis-associated p62/SQSTM1 mutants show slower inner fluidity

Omar

Ichimura

Kageyama

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

A series of amyotrophic lateral sclerosis (ALS)-related proteins such as FUS, TDP-43 and hnRNPA1 has an ability to be liquid-liquid phase separation, and their disease-related mutations cause the transition of their responsible liquid droplets to aggregates. Missense mutations in SQSTM1/p62, which have been identified throughout the gene, are associated with ALS, frontotemporal degeneration (FTD) and Pagets disease of bone. SQSTM1/p62 protein forms liquid-droplets through the interaction with ubiquitinated proteins, and the droplet serves as a platform of autophagosome formation and anti-oxidative stress response via the LC3-interacting region (LIR) and Keap1-interacting region (KIR), respectively. However, it remains unclear whether ALS/FTD-related p62 mutations in LIR and KIR form aberrant liquid droplets, cause defective autophagy and stress response or both. To evaluate the effects of ALS/FTD-related p62 mutations in LIR and KIR on a major oxidative stress system, the Keap1-Nrf2 pathway and the autophagic turnover, we developed systems that enable to monitor them with high sensitivity. These systems revealed that some mutants but not all have their less abilities on the Nrf2-activation and show the delayed turnover. By contrast, while the sufficient ability to form liquid droplets, all droplets consisting of p62 mutants showed slower inner fluidity. These results indicate that like other ALS-related mutant proteins, a primary defect in ALS/FTD with p62 missense mutations is a qualitative change of p62-liquid droplets.

show abstract

p62/SQSTM1-droplet serves as a platform for autophagosome formation and anti-oxidative stress response

Cited by 165 publications

References 69 publications

SQSTM1/p62 Promotes Cell Growth and Triggers Autophagy in Papillary Thyroid Cancer by Regulating the AKT/AMPK/mTOR Signaling Pathway

SQSTM1/p62 Promotes Cell Growth and Triggers Autophagy in Papillary Thyroid Cancer by Regulating the AKT/AMPK/mTOR Signaling Pathway

Protective Mechanism of Humanin Against Oxidative Stress in Aging-Related Cardiovascular Diseases

Droplets of amyotrophic lateral sclerosis-associated p62/SQSTM1 mutants show slower inner fluidity

Contact Info

Product

Resources

About