{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T19:58:56Z","timestamp":1790366336813,"version":"4.1.0"},"reference-count":41,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,10,10]],"date-time":"2019-10-10T00:00:00Z","timestamp":1570665600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002341","name":"Academy of Finland","doi-asserted-by":"publisher","award":["315459"],"award-info":[{"award-number":["315459"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002341","name":"Academy of Finland","doi-asserted-by":"publisher","award":["315460"],"award-info":[{"award-number":["315460"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002341","name":"Academy of Finland","doi-asserted-by":"publisher","award":["307866"],"award-info":[{"award-number":["307866"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002341","name":"Academy of Finland","doi-asserted-by":"publisher","award":["288659"],"award-info":[{"award-number":["288659"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010114","name":"Yrj\u00f6 Jahnsson Foundation","doi-asserted-by":"publisher","award":["20187070"],"award-info":[{"award-number":["20187070"]}],"id":[{"id":"10.13039\/100010114","id-type":"DOI","asserted-by":"publisher"}]},{"name":"ALS tutkimuksen tuki ry.","award":["-"],"award-info":[{"award-number":["-"]}]},{"DOI":"10.13039\/501100006306","name":"Sigrid Jus\u00e9liuksen S\u00e4\u00e4ti\u00f6","doi-asserted-by":"publisher","award":["-"],"award-info":[{"award-number":["-"]}],"id":[{"id":"10.13039\/501100006306","id-type":"DOI","asserted-by":"publisher"}]},{"name":"VTR grant, Kuopio University Hospital","award":["5772816"],"award-info":[{"award-number":["5772816"]}]},{"name":"Strategic Neuroscience Funding of the University of Eastern Finland","award":["-"],"award-info":[{"award-number":["-"]}]},{"name":"Neurocenter Finland, AlzTrans pilot project","award":["-"],"award-info":[{"award-number":["-"]}]},{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["740264"],"award-info":[{"award-number":["740264"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Dysfunctional autophagy or ubiquitin-proteasome system (UPS) are suggested to underlie abnormal protein aggregation in neurodegenerative diseases. Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS)-associated C9orf72 is implicated in autophagy, but whether it activates or inhibits autophagy is partially controversial. Here, we utilized knockdown or overexpression of C9orf72 in mouse N2a neuroblastoma cells or cultured neurons to elucidate the potential role of C9orf72 proteins in autophagy and UPS. Induction of autophagy in C9orf72 knockdown N2a cells led to decreased LC3BI to LC3BII conversion, p62 degradation, and formation of LC3-containing autophagosomes, suggesting compromised autophagy. Proteasomal activity was slightly decreased. No changes in autophagy nor proteasomal activity in C9orf72-overexpressing N2a cells were observed. However, in these cells, autophagy induction by serum starvation or rapamycin led to significantly decreased C9orf72 levels. The decreased levels of C9orf72 in serum-starved N2a cells were restored by the proteasomal inhibitor lactacystin, but not by the autophagy inhibitor bafilomycin A1 (BafA1) treatment. These data suggest that C9orf72 undergoes proteasomal degradation in N2a cells during autophagy. Lactacystin significantly elevated C9orf72 levels in N2a cells and neurons, further suggesting UPS-mediated regulation. In rapamycin and BafA1-treated neurons, C9orf72 levels were significantly increased. Altogether, these findings corroborate the previously suggested regulatory role for C9orf72 in autophagy and suggest cell type-dependent regulation of C9orf72 levels via UPS and\/or autophagy.<\/jats:p>","DOI":"10.3390\/cells8101233","type":"journal-article","created":{"date-parts":[[2019,10,11]],"date-time":"2019-10-11T03:07:11Z","timestamp":1570763231000},"page":"1233","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["C9orf72 Proteins Regulate Autophagy and Undergo Autophagosomal or Proteasomal Degradation in a Cell Type-Dependent Manner"],"prefix":"10.3390","volume":"8","author":[{"given":"Stina","family":"Leskel\u00e4","sequence":"first","affiliation":[{"name":"A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nadine","family":"Huber","sequence":"additional","affiliation":[{"name":"A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4672-0850","authenticated-orcid":false,"given":"Hannah","family":"Rostalski","sequence":"additional","affiliation":[{"name":"A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teemu","family":"Natunen","sequence":"additional","affiliation":[{"name":"Institute of Biomedicine, Yliopistonranta 1E, University of Eastern Finland, 70211 Kuopio, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4969-5101","authenticated-orcid":false,"given":"Anne M.","family":"Remes","sequence":"additional","affiliation":[{"name":"Unit of Clinical Neuroscience, Neurology, University of Oulu, P.O. Box 8000, University of Oulu, 90014 Oulu, Finland"},{"name":"MRC Oulu, Oulu University Hospital, P.O. Box 8000, University of Oulu, 90014 Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mari","family":"Takalo","sequence":"additional","affiliation":[{"name":"Institute of Biomedicine, Yliopistonranta 1E, University of Eastern Finland, 70211 Kuopio, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mikko","family":"Hiltunen","sequence":"additional","affiliation":[{"name":"Institute of Biomedicine, Yliopistonranta 1E, University of Eastern Finland, 70211 Kuopio, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0959-2957","authenticated-orcid":false,"given":"Annakaisa","family":"Haapasalo","sequence":"additional","affiliation":[{"name":"A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"88","DOI":"10.2174\/1745017901309010088","article-title":"Epidemiology of Early-Onset Dementia: A Review of the Literature","volume":"9","author":"Vieira","year":"2013","journal-title":"Clin. Pract. Epidemiol. Ment. Health"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1672","DOI":"10.1016\/S0140-6736(15)00461-4","article-title":"Frontotemporal Dementia","volume":"386","author":"Bang","year":"2015","journal-title":"Lancet"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1038\/nrneurol.2014.184","article-title":"The Phenotypic Variability of Amyotrophic Lateral Sclerosis","volume":"10","author":"Swinnen","year":"2014","journal-title":"Nat. Rev. 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