Huimei Liu, Hui Mao, Xueqian Ouyang, Ruirui Lu, Lanfang Li
Mitochondria, the dynamic organelles responsible for energy production and cellular metabolism, have the metabolic function of extracting energy from nutrients and synthesizing crucial metabolites. Nevertheless, recent research unveils that intercellular mitochondrial transfer by tunneling nanotubes, tumor microtubes, gap junction intercellular communication, extracellular vesicles, endocytosis and cell fusion may regulate mitochondrial function within recipient cells, potentially contributing to disease treatment, such as nonalcoholic steatohepatitis, glioblastoma, ischemic stroke, bladder cancer and neurodegenerative diseases. This review introduces the principal approaches to intercellular mitochondrial transfer and examines its role in various diseases. Furthermore, we provide a comprehensive overview of the inhibitors and activators of intercellular mitochondrial transfer, offering a unique perspective to illustrate the relationship between intercellular mitochondrial transfer and diseases.
{"title":"Intercellular Mitochondrial Transfer: The Novel Therapeutic Mechanism for Diseases.","authors":"Huimei Liu, Hui Mao, Xueqian Ouyang, Ruirui Lu, Lanfang Li","doi":"10.1111/tra.12951","DOIUrl":"https://doi.org/10.1111/tra.12951","url":null,"abstract":"<p><p>Mitochondria, the dynamic organelles responsible for energy production and cellular metabolism, have the metabolic function of extracting energy from nutrients and synthesizing crucial metabolites. Nevertheless, recent research unveils that intercellular mitochondrial transfer by tunneling nanotubes, tumor microtubes, gap junction intercellular communication, extracellular vesicles, endocytosis and cell fusion may regulate mitochondrial function within recipient cells, potentially contributing to disease treatment, such as nonalcoholic steatohepatitis, glioblastoma, ischemic stroke, bladder cancer and neurodegenerative diseases. This review introduces the principal approaches to intercellular mitochondrial transfer and examines its role in various diseases. Furthermore, we provide a comprehensive overview of the inhibitors and activators of intercellular mitochondrial transfer, offering a unique perspective to illustrate the relationship between intercellular mitochondrial transfer and diseases.</p>","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142141198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Enterocytes and liver cells fulfill important metabolic and barrier functions and are responsible for crucial vectorial secretive and absorptive processes. To date, genetic diseases affecting metabolic enzymes or transmembrane transporters in the intestine and the liver are better comprehended than mutations affecting intracellular trafficking. In this review, we explore the emerging knowledge on intracellular trafficking defects and their clinical manifestations in both the intestine and the liver. We provide a detailed overview including more investigated diseases such as the canonical, variant and associated forms of microvillus inclusion disease, as well as recently described pathologies, highlighting the complexity and disease relevance of several trafficking pathways. We give examples of how intracellular trafficking hubs, such as the apical recycling endosome system, the trans-Golgi network, lysosomes, or the Golgi-to-endoplasmic reticulum transport are involved in the pathomechanism and lead to disease. Ultimately, understanding these processes could spark novel therapeutic approaches, which would greatly improve the quality of life of the affected patients.
{"title":"Intracellular Trafficking Defects in Congenital Intestinal and Hepatic Diseases.","authors":"Luca Szabó, Adam R Pollio, Georg Friedrich Vogel","doi":"10.1111/tra.12954","DOIUrl":"https://doi.org/10.1111/tra.12954","url":null,"abstract":"<p><p>Enterocytes and liver cells fulfill important metabolic and barrier functions and are responsible for crucial vectorial secretive and absorptive processes. To date, genetic diseases affecting metabolic enzymes or transmembrane transporters in the intestine and the liver are better comprehended than mutations affecting intracellular trafficking. In this review, we explore the emerging knowledge on intracellular trafficking defects and their clinical manifestations in both the intestine and the liver. We provide a detailed overview including more investigated diseases such as the canonical, variant and associated forms of microvillus inclusion disease, as well as recently described pathologies, highlighting the complexity and disease relevance of several trafficking pathways. We give examples of how intracellular trafficking hubs, such as the apical recycling endosome system, the trans-Golgi network, lysosomes, or the Golgi-to-endoplasmic reticulum transport are involved in the pathomechanism and lead to disease. Ultimately, understanding these processes could spark novel therapeutic approaches, which would greatly improve the quality of life of the affected patients.</p>","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142073935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SNX32 is a member of the evolutionarily conserved Phox (PX) homology domain- and Bin/Amphiphysin/Rvs (BAR) domain- containing sorting nexin (SNX-BAR) family of proteins, which play important roles in sorting and membrane trafficking of endosomal cargoes. Although SNX32 shares the highest amino acid sequence homology with SNX6, and has been believed to function redundantly with SNX5 and SNX6 in retrieval of the cation-independent mannose-6-phosphate receptor (CI-MPR) from endosomes to the trans-Golgi network (TGN), its role(s) in intracellular protein trafficking remains largely unexplored. Here, we report that it functions in parallel with SNX1 in mediating epidermal growth factor (EGF)-stimulated postendocytic trafficking of the epidermal growth factor receptor (EGFR). Moreover, SNX32 interacts directly with EGFR, and recruits SNX5 to promote sorting of EGF-EGFR into multivesicular bodies (MVBs) for lysosomal degradation. Thus, SNX32 functions distinctively from other SNX-BAR proteins to mediate signaling-coupled endolysosomal trafficking of EGFR.
{"title":"SNX32 Regulates Sorting and Trafficking of Activated EGFR to the Lysosomal Degradation Pathway.","authors":"Dou Wang, Xia Zhao, Panpan Wang, Jia-Jia Liu","doi":"10.1111/tra.12952","DOIUrl":"10.1111/tra.12952","url":null,"abstract":"<p><p>SNX32 is a member of the evolutionarily conserved Phox (PX) homology domain- and Bin/Amphiphysin/Rvs (BAR) domain- containing sorting nexin (SNX-BAR) family of proteins, which play important roles in sorting and membrane trafficking of endosomal cargoes. Although SNX32 shares the highest amino acid sequence homology with SNX6, and has been believed to function redundantly with SNX5 and SNX6 in retrieval of the cation-independent mannose-6-phosphate receptor (CI-MPR) from endosomes to the trans-Golgi network (TGN), its role(s) in intracellular protein trafficking remains largely unexplored. Here, we report that it functions in parallel with SNX1 in mediating epidermal growth factor (EGF)-stimulated postendocytic trafficking of the epidermal growth factor receptor (EGFR). Moreover, SNX32 interacts directly with EGFR, and recruits SNX5 to promote sorting of EGF-EGFR into multivesicular bodies (MVBs) for lysosomal degradation. Thus, SNX32 functions distinctively from other SNX-BAR proteins to mediate signaling-coupled endolysosomal trafficking of EGFR.</p>","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141789089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nidia Carolina Moreno-Corona, Mercedes Piedad de León-Bautista, Moises León-Juárez, Araceli Hernández-Flores, Juan Carlos Barragán-Gálvez, Orestes López-Ortega
Processes such as cell migration, phagocytosis, endocytosis, and exocytosis refer to the intense exchange of information between the internal and external environment in the cells, known as vesicular trafficking. In eukaryotic cells, these essential cellular crosstalks are controlled by Rab GTPases proteins through diverse adaptor proteins like SNAREs complex, coat proteins, phospholipids, kinases, phosphatases, molecular motors, actin, or tubulin cytoskeleton, among others, all necessary for appropriate mobilization of vesicles and distribution of molecules. Considering these molecular events, Rab GTPases are critical components in specific biological processes of immune cells, and many reports refer primarily to macrophages; therefore, in this review, we address specific functions in immune cells, concretely in the mechanism by which the GTPase contributes in dendritic cells (DCs) and, T/B lymphocytes.
{"title":"Rab GTPases, Active Members in Antigen-Presenting Cells, and T Lymphocytes.","authors":"Nidia Carolina Moreno-Corona, Mercedes Piedad de León-Bautista, Moises León-Juárez, Araceli Hernández-Flores, Juan Carlos Barragán-Gálvez, Orestes López-Ortega","doi":"10.1111/tra.12950","DOIUrl":"https://doi.org/10.1111/tra.12950","url":null,"abstract":"<p><p>Processes such as cell migration, phagocytosis, endocytosis, and exocytosis refer to the intense exchange of information between the internal and external environment in the cells, known as vesicular trafficking. In eukaryotic cells, these essential cellular crosstalks are controlled by Rab GTPases proteins through diverse adaptor proteins like SNAREs complex, coat proteins, phospholipids, kinases, phosphatases, molecular motors, actin, or tubulin cytoskeleton, among others, all necessary for appropriate mobilization of vesicles and distribution of molecules. Considering these molecular events, Rab GTPases are critical components in specific biological processes of immune cells, and many reports refer primarily to macrophages; therefore, in this review, we address specific functions in immune cells, concretely in the mechanism by which the GTPase contributes in dendritic cells (DCs) and, T/B lymphocytes.</p>","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141459502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Endosomal trafficking of TrkA is a critical process for nerve growth factor (NGF)-dependent neuronal cell survival and differentiation. The small GTPase ADP-ribosylation factor 6 (Arf6) is implicated in NGF-dependent processes in PC12 cells through endosomal trafficking and actin cytoskeleton reorganization. However, the regulatory mechanism for Arf6 in NGF signaling is largely unknown. In this study, we demonstrated that EFA6A, an Arf6-specific guanine nucleotide exchange factor, was abundantly expressed in PC12 cells and that knockdown of EFA6A significantly inhibited NGF-dependent Arf6 activation, TrkA recycling from early endosomes to the cell surface, prolonged ERK1/2 phosphorylation, and neurite outgrowth. We also demonstrated that EFA6A forms a protein complex with TrkA through its N-terminal region, thereby enhancing its catalytic activity for Arf6. Similarly, we demonstrated that EFA6A forms a protein complex with TrkA in cultured dorsal root ganglion (DRG) neurons. Furthermore, cultured DRG neurons from EFA6A knockout mice exhibited disturbed NGF-dependent TrkA trafficking compared with wild-type neurons. These findings provide the first evidence for EFA6A as a key regulator of NGF-dependent TrkA trafficking and signaling.
{"title":"EFA6A, an Exchange Factor for Arf6, Regulates NGF-Dependent TrkA Recycling From Early Endosomes and Neurite Outgrowth in PC12 Cells.","authors":"Masahiro Fukaya, Kanta Ibuchi, Takeyuki Sugawara, Makoto Itakura, Akiko Ito, Tomoko Shiroshima, Yoshinobu Hara, Hirotsugu Okamoto, Frédéric Luton, Hiroyuki Sakagami","doi":"10.1111/tra.12936","DOIUrl":"10.1111/tra.12936","url":null,"abstract":"<p><p>Endosomal trafficking of TrkA is a critical process for nerve growth factor (NGF)-dependent neuronal cell survival and differentiation. The small GTPase ADP-ribosylation factor 6 (Arf6) is implicated in NGF-dependent processes in PC12 cells through endosomal trafficking and actin cytoskeleton reorganization. However, the regulatory mechanism for Arf6 in NGF signaling is largely unknown. In this study, we demonstrated that EFA6A, an Arf6-specific guanine nucleotide exchange factor, was abundantly expressed in PC12 cells and that knockdown of EFA6A significantly inhibited NGF-dependent Arf6 activation, TrkA recycling from early endosomes to the cell surface, prolonged ERK1/2 phosphorylation, and neurite outgrowth. We also demonstrated that EFA6A forms a protein complex with TrkA through its N-terminal region, thereby enhancing its catalytic activity for Arf6. Similarly, we demonstrated that EFA6A forms a protein complex with TrkA in cultured dorsal root ganglion (DRG) neurons. Furthermore, cultured DRG neurons from EFA6A knockout mice exhibited disturbed NGF-dependent TrkA trafficking compared with wild-type neurons. These findings provide the first evidence for EFA6A as a key regulator of NGF-dependent TrkA trafficking and signaling.</p>","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140899567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katherine Y Peng, Braison Liemisa, Jonathan Pasato, Pasquale D'Acunzo, Monika Pawlik, Adriana Heguy, Sai C Penikalapati, Amanda Labuza, Harshitha Pidikiti, Melissa J Alldred, Stephen D Ginsberg, Efrat Levy, Paul M Mathews
The polymorphic APOE gene is the greatest genetic determinant of sporadic Alzheimer's disease risk: the APOE4 allele increases risk, while the APOE2 allele is neuroprotective compared with the risk-neutral APOE3 allele. The neuronal endosomal system is inherently vulnerable during aging, and APOE4 exacerbates this vulnerability by driving an enlargement of early endosomes and reducing exosome release in the brain of humans and mice. We hypothesized that the protective effects of APOE2 are, in part, mediated through the endosomal pathway. Messenger RNA analyses showed that APOE2 leads to an enrichment of endosomal pathways in the brain when compared with both APOE3 and APOE4. Moreover, we show age-dependent alterations in the recruitment of key endosomal regulatory proteins to vesicle compartments when comparing APOE2 to APOE3. In contrast to the early endosome enlargement previously shown in Alzheimer's disease and APOE4 models, we detected similar morphology and abundance of early endosomes and retromer-associated vesicles within cortical neurons of aged APOE2 targeted-replacement mice compared with APOE3. Additionally, we observed increased brain extracellular levels of endosome-derived exosomes in APOE2 compared with APOE3 mice during aging, consistent with enhanced endosomal cargo clearance by exosomes to the extracellular space. Our findings thus demonstrate that APOE2 enhances an endosomal clearance pathway, which has been shown to be impaired by APOE4 and which may be protective due to APOE2 expression during brain aging.
{"title":"Apolipoprotein E2 Expression Alters Endosomal Pathways in a Mouse Model With Increased Brain Exosome Levels During Aging.","authors":"Katherine Y Peng, Braison Liemisa, Jonathan Pasato, Pasquale D'Acunzo, Monika Pawlik, Adriana Heguy, Sai C Penikalapati, Amanda Labuza, Harshitha Pidikiti, Melissa J Alldred, Stephen D Ginsberg, Efrat Levy, Paul M Mathews","doi":"10.1111/tra.12937","DOIUrl":"10.1111/tra.12937","url":null,"abstract":"<p><p>The polymorphic APOE gene is the greatest genetic determinant of sporadic Alzheimer's disease risk: the APOE4 allele increases risk, while the APOE2 allele is neuroprotective compared with the risk-neutral APOE3 allele. The neuronal endosomal system is inherently vulnerable during aging, and APOE4 exacerbates this vulnerability by driving an enlargement of early endosomes and reducing exosome release in the brain of humans and mice. We hypothesized that the protective effects of APOE2 are, in part, mediated through the endosomal pathway. Messenger RNA analyses showed that APOE2 leads to an enrichment of endosomal pathways in the brain when compared with both APOE3 and APOE4. Moreover, we show age-dependent alterations in the recruitment of key endosomal regulatory proteins to vesicle compartments when comparing APOE2 to APOE3. In contrast to the early endosome enlargement previously shown in Alzheimer's disease and APOE4 models, we detected similar morphology and abundance of early endosomes and retromer-associated vesicles within cortical neurons of aged APOE2 targeted-replacement mice compared with APOE3. Additionally, we observed increased brain extracellular levels of endosome-derived exosomes in APOE2 compared with APOE3 mice during aging, consistent with enhanced endosomal cargo clearance by exosomes to the extracellular space. Our findings thus demonstrate that APOE2 enhances an endosomal clearance pathway, which has been shown to be impaired by APOE4 and which may be protective due to APOE2 expression during brain aging.</p>","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11141728/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141080979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kwesi Z. Tandoh, Ana Victoria Ibarra‐Meneses, David Langlais, Martin Olivier, Ana Claudia Torrecilhas, Christopher Fernandez‐Prada, Neta Regev‐Rudzki, Nancy O. Duah‐Quashie
The protozoan parasites Plasmodium falciparum, Leishmania spp. and Trypanosoma cruzi continue to exert a significant toll on the disease landscape of the human population in sub‐Saharan Africa and Latin America. Control measures have helped reduce the burden of their respective diseases—malaria, leishmaniasis and Chagas disease—in endemic regions. However, the need for new drugs, innovative vaccination strategies and molecular markers of disease severity and outcomes has emerged because of developing antimicrobial drug resistance, comparatively inadequate or absent vaccines, and a lack of trustworthy markers of morbid outcomes. Extracellular vesicles (EVs) have been widely reported to play a role in the biology and pathogenicity of P. falciparum, Leishmania spp. and T. cruzi ever since they were discovered. EVs are secreted by a yet to be fully understood mechanism in protozoans into the extracellular milieu and carry a cargo of diverse molecules that reflect the originator cell's metabolic state. Although our understanding of the biogenesis and function of EVs continues to deepen, the question of how EVs in P. falciparum, Leishmania spp. and T. cruzi can serve as targets for a translational agenda into clinical and public health interventions is yet to be fully explored. Here, as a consortium of protozoan researchers, we outline a plan for future researchers and pose three questions to direct an EV's translational agenda in P. falciparum, Leishmania spp. and T. cruzi. We opine that in the long term, executing this blueprint will help bridge the current unmet needs of these medically important protozoan diseases in sub‐Saharan Africa and Latin America.
原生动物寄生虫恶性疟原虫、利什曼原虫和南美锥虫继续对撒哈拉以南非洲和拉丁美洲人口的疾病状况造成重大影响。控制措施有助于减轻疟疾、利什曼病和南美锥虫病流行地区的疾病负担。然而,由于抗微生物药物耐药性的不断发展、疫苗相对不足或缺失,以及缺乏可信的发病结果标记物,因此出现了对新药物、创新疫苗接种策略以及疾病严重程度和结果分子标记物的需求。细胞外囊泡(EVs)自被发现以来,就被广泛报道在恶性疟原虫、利什曼原虫属和克鲁兹疟原虫的生物学和致病性中发挥作用。EVs是通过原生动物尚未完全了解的机制分泌到细胞外环境中的,其携带的各种分子反映了原生细胞的新陈代谢状态。尽管我们对 EVs 的生物发生和功能的理解在不断加深,但恶性疟原虫、利什曼原虫和克鲁斯原虫中的 EVs 如何作为转化为临床和公共卫生干预议程的目标,这一问题仍有待充分探讨。在此,作为一个原生动物研究人员联盟,我们为未来的研究人员概述了一项计划,并提出了三个问题,以指导恶性疟原虫、利什曼原虫属和克鲁斯原虫的 EV 转化议程。我们认为,从长远来看,执行这一蓝图将有助于满足撒哈拉以南非洲和拉丁美洲目前对这些具有重要医学意义的原生动物疾病尚未满足的需求。
{"title":"Extracellular Vesicles: Translational Agenda Questions for Three Protozoan Parasites","authors":"Kwesi Z. Tandoh, Ana Victoria Ibarra‐Meneses, David Langlais, Martin Olivier, Ana Claudia Torrecilhas, Christopher Fernandez‐Prada, Neta Regev‐Rudzki, Nancy O. Duah‐Quashie","doi":"10.1111/tra.12935","DOIUrl":"https://doi.org/10.1111/tra.12935","url":null,"abstract":"The protozoan parasites <jats:italic>Plasmodium falciparum</jats:italic>, <jats:italic>Leishmania</jats:italic> spp<jats:italic>.</jats:italic> and <jats:italic>Trypanosoma cruzi</jats:italic> continue to exert a significant toll on the disease landscape of the human population in sub‐Saharan Africa and Latin America. Control measures have helped reduce the burden of their respective diseases—malaria, leishmaniasis and Chagas disease—in endemic regions. However, the need for new drugs, innovative vaccination strategies and molecular markers of disease severity and outcomes has emerged because of developing antimicrobial drug resistance, comparatively inadequate or absent vaccines, and a lack of trustworthy markers of morbid outcomes. Extracellular vesicles (EVs) have been widely reported to play a role in the biology and pathogenicity of <jats:italic>P. falciparum</jats:italic>, <jats:italic>Leishmania</jats:italic> spp<jats:italic>.</jats:italic> and <jats:italic>T. cruzi</jats:italic> ever since they were discovered. EVs are secreted by a yet to be fully understood mechanism in protozoans into the extracellular milieu and carry a cargo of diverse molecules that reflect the originator cell's metabolic state. Although our understanding of the biogenesis and function of EVs continues to deepen, the question of how EVs in <jats:italic>P. falciparum</jats:italic>, <jats:italic>Leishmania</jats:italic> spp<jats:italic>.</jats:italic> and <jats:italic>T. cruzi</jats:italic> can serve as targets for a translational agenda into clinical and public health interventions is yet to be fully explored. Here, as a consortium of protozoan researchers, we outline a plan for future researchers and pose three questions to direct an EV's translational agenda in <jats:italic>P. falciparum</jats:italic>, <jats:italic>Leishmania</jats:italic> spp. and <jats:italic>T. cruzi</jats:italic>. We opine that in the long term, executing this blueprint will help bridge the current unmet needs of these medically important protozoan diseases in sub‐Saharan Africa and Latin America.","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140616919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Johanna Mayer, Dominik Boeck, Michelle Werner, Daniela Frankenhauser, Stephan Geley, Hesso Farhan, Makoto Shimozawa, Per Nilsson
Alzheimer's disease (AD) pathology is characterized by amyloid beta (Aβ) plaques and dysfunctional autophagy. Aβ is generated by sequential proteolytic cleavage of amyloid precursor protein (APP), and the site of intracellular APP processing is highly debated, which may include autophagosomes. Here, we investigated the involvement of autophagy, including the role of ATG9 in APP intracellular trafficking and processing by applying the RUSH system, which allows studying the transport of fluorescently labeled mCherry‐APP‐EGFP in a systematic way, starting from the endoplasmic reticulum. HeLa cells, expressing the RUSH mCherry‐APP‐EGFP system, were investigated by live cell imaging, immunofluorescence, and Western blot. We found that mCherry‐APP‐EGFP passed through the Golgi faster in ATG9 knockout cells. Furthermore, ATG9 deletion shifted mCherry‐APP‐EGFP from early endosomes and lysosomes toward the plasma membrane concomitant with reduced endocytosis. Importantly, this alteration in mCherry‐APP‐EGFP transport resulted in increased secreted mCherry‐soluble APP and C‐terminal fragment‐EGFP. These effects were also phenocopied by pharmacological inhibition of ULK1, indicating that autophagy is regulating the intracellular trafficking and processing of APP. These findings contribute to the understanding of the role of autophagy in APP metabolism and could potentially have implications for new therapeutic approaches for AD.
阿尔茨海默病(AD)的病理特征是淀粉样 beta(Aβ)斑块和自噬功能障碍。淀粉样β是由淀粉样前体蛋白(APP)的连续蛋白水解产生的,而细胞内APP的加工部位还存在很大争议,其中可能包括自噬体。RUSH系统可以从内质网开始系统地研究荧光标记的mCherry-APP-EGFP的转运,我们在此研究了自噬的参与,包括ATG9在APP胞内转运和处理中的作用。我们通过活细胞成像、免疫荧光和 Western 印迹对表达 RUSH mCherry-APP-EGFP 系统的 HeLa 细胞进行了研究。我们发现,在 ATG9 基因敲除的细胞中,mCherry-APP-EGFP 通过高尔基体的速度更快。此外,ATG9 基因缺失会使 mCherry-APP-EGFP 从早期内体和溶酶体转移到质膜,同时内吞作用也会减弱。重要的是,mCherry-APP-EGFP转运的这种改变导致分泌的mCherry-可溶性APP和C-末端片段-EGFP增加。药物抑制ULK1也会产生这些效应,这表明自噬正在调节APP的胞内转运和处理。这些发现有助于人们了解自噬在APP代谢中的作用,并有可能对AD的新治疗方法产生影响。
{"title":"Inhibition of Autophagy Alters Intracellular Transport of APP Resulting in Increased APP Processing","authors":"Johanna Mayer, Dominik Boeck, Michelle Werner, Daniela Frankenhauser, Stephan Geley, Hesso Farhan, Makoto Shimozawa, Per Nilsson","doi":"10.1111/tra.12934","DOIUrl":"https://doi.org/10.1111/tra.12934","url":null,"abstract":"Alzheimer's disease (AD) pathology is characterized by amyloid beta (Aβ) plaques and dysfunctional autophagy. Aβ is generated by sequential proteolytic cleavage of amyloid precursor protein (APP), and the site of intracellular APP processing is highly debated, which may include autophagosomes. Here, we investigated the involvement of autophagy, including the role of ATG9 in APP intracellular trafficking and processing by applying the RUSH system, which allows studying the transport of fluorescently labeled mCherry‐APP‐EGFP in a systematic way, starting from the endoplasmic reticulum. HeLa cells, expressing the RUSH mCherry‐APP‐EGFP system, were investigated by live cell imaging, immunofluorescence, and Western blot. We found that mCherry‐APP‐EGFP passed through the Golgi faster in ATG9 knockout cells. Furthermore, ATG9 deletion shifted mCherry‐APP‐EGFP from early endosomes and lysosomes toward the plasma membrane concomitant with reduced endocytosis. Importantly, this alteration in mCherry‐APP‐EGFP transport resulted in increased secreted mCherry‐soluble APP and C‐terminal fragment‐EGFP. These effects were also phenocopied by pharmacological inhibition of ULK1, indicating that autophagy is regulating the intracellular trafficking and processing of APP. These findings contribute to the understanding of the role of autophagy in APP metabolism and could potentially have implications for new therapeutic approaches for AD.","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140562055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kevin Ostacolo, Adrián López García de Lomana, Clémence Larat, Valgerdur Hjaltalin, Kristrun Yr Holm, Sigríður S. Hlynsdóttir, Margaret Soucheray, Linda Sooman, Ottar Rolfsson, Nevan J. Krogan, Eirikur Steingrimsson, Danielle L. Swaney, Margret H. Ogmundsdottir
Macroautophagy/autophagy is an essential catabolic process that targets a wide variety of cellular components including proteins, organelles, and pathogens. ATG7, a protein involved in the autophagy process, plays a crucial role in maintaining cellular homeostasis and can contribute to the development of diseases such as cancer. ATG7 initiates autophagy by facilitating the lipidation of the ATG8 proteins in the growing autophagosome membrane. The noncanonical isoform ATG7(2) is unable to perform ATG8 lipidation; however, its cellular regulation and function are unknown. Here, we uncovered a distinct regulation and function of ATG7(2) in contrast with ATG7(1), the canonical isoform. First, affinity‐purification mass spectrometry analysis revealed that ATG7(2) establishes direct protein–protein interactions (PPIs) with metabolic proteins, whereas ATG7(1) primarily interacts with autophagy machinery proteins. Furthermore, we identified that ATG7(2) mediates a decrease in metabolic activity, highlighting a novel splice‐dependent function of this important autophagy protein. Then, we found a divergent expression pattern of ATG7(1) and ATG7(2) across human tissues. Conclusively, our work uncovers the divergent patterns of expression, protein interactions, and function of ATG7(2) in contrast to ATG7(1). These findings suggest a molecular switch between main catabolic processes through isoform‐dependent expression of a key autophagy gene.
{"title":"ATG7(2) Interacts With Metabolic Proteins and Regulates Central Energy Metabolism","authors":"Kevin Ostacolo, Adrián López García de Lomana, Clémence Larat, Valgerdur Hjaltalin, Kristrun Yr Holm, Sigríður S. Hlynsdóttir, Margaret Soucheray, Linda Sooman, Ottar Rolfsson, Nevan J. Krogan, Eirikur Steingrimsson, Danielle L. Swaney, Margret H. Ogmundsdottir","doi":"10.1111/tra.12933","DOIUrl":"https://doi.org/10.1111/tra.12933","url":null,"abstract":"Macroautophagy/autophagy is an essential catabolic process that targets a wide variety of cellular components including proteins, organelles, and pathogens. ATG7, a protein involved in the autophagy process, plays a crucial role in maintaining cellular homeostasis and can contribute to the development of diseases such as cancer. ATG7 initiates autophagy by facilitating the lipidation of the ATG8 proteins in the growing autophagosome membrane. The noncanonical isoform ATG7(2) is unable to perform ATG8 lipidation; however, its cellular regulation and function are unknown. Here, we uncovered a distinct regulation and function of <jats:italic>ATG7(2)</jats:italic> in contrast with <jats:italic>ATG7(1)</jats:italic>, the canonical isoform. First, affinity‐purification mass spectrometry analysis revealed that ATG7(2) establishes direct protein–protein interactions (PPIs) with metabolic proteins, whereas ATG7(1) primarily interacts with autophagy machinery proteins. Furthermore, we identified that ATG7(2) mediates a decrease in metabolic activity, highlighting a novel splice‐dependent function of this important autophagy protein. Then, we found a divergent expression pattern of <jats:italic>ATG7(1)</jats:italic> and <jats:italic>ATG7(2)</jats:italic> across human tissues. Conclusively, our work uncovers the divergent patterns of expression, protein interactions, and function of ATG7(2) in contrast to ATG7(1). These findings suggest a molecular switch between main catabolic processes through isoform‐dependent expression of a key autophagy gene.","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140562625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alzheimer's disease is associated with increased levels of amyloid beta (Aβ) generated by sequential intracellular cleavage of amyloid precursor protein (APP) by membrane-bound secretases. However, the spatial and temporal APP cleavage events along the trafficking pathways are poorly defined. Here, we use the Retention Using Selective Hooks (RUSH) to compare in real time the anterograde trafficking and temporal cleavage events of wild-type APP (APPwt) with the pathogenic Swedish APP (APPswe) and the disease-protective Icelandic APP (APPice). The analyses revealed differences in the trafficking profiles and processing between APPwt and the APP familial mutations. While APPwt was predominantly processed by the β-secretase, BACE1, following Golgi transport to the early endosomes, the transit of APPswe through the Golgi was prolonged and associated with enhanced amyloidogenic APP processing and Aβ secretion. A 20°C block in cargo exit from the Golgi confirmed β- and γ-secretase processing of APPswe in the Golgi. Inhibition of the β-secretase, BACE1, restored APPswe anterograde trafficking profile to that of APPwt. APPice was transported rapidly through the Golgi to the early endosomes with low levels of Aβ production. This study has revealed different intracellular locations for the preferential cleavage of APPwt and APPswe and Aβ production, and the Golgi as the major processing site for APPswe, findings relevant to understand the molecular basis of Alzheimer's disease.
{"title":"Spatial-Temporal Mapping Reveals the Golgi as the Major Processing Site for the Pathogenic Swedish APP Mutation: Familial APP Mutant Shifts the Major APP Processing Site.","authors":"Jingqi Wang, Paul A Gleeson, Lou Fourriere","doi":"10.1111/tra.12932","DOIUrl":"10.1111/tra.12932","url":null,"abstract":"<p><p>Alzheimer's disease is associated with increased levels of amyloid beta (Aβ) generated by sequential intracellular cleavage of amyloid precursor protein (APP) by membrane-bound secretases. However, the spatial and temporal APP cleavage events along the trafficking pathways are poorly defined. Here, we use the Retention Using Selective Hooks (RUSH) to compare in real time the anterograde trafficking and temporal cleavage events of wild-type APP (APPwt) with the pathogenic Swedish APP (APPswe) and the disease-protective Icelandic APP (APPice). The analyses revealed differences in the trafficking profiles and processing between APPwt and the APP familial mutations. While APPwt was predominantly processed by the β-secretase, BACE1, following Golgi transport to the early endosomes, the transit of APPswe through the Golgi was prolonged and associated with enhanced amyloidogenic APP processing and Aβ secretion. A 20°C block in cargo exit from the Golgi confirmed β- and γ-secretase processing of APPswe in the Golgi. Inhibition of the β-secretase, BACE1, restored APPswe anterograde trafficking profile to that of APPwt. APPice was transported rapidly through the Golgi to the early endosomes with low levels of Aβ production. This study has revealed different intracellular locations for the preferential cleavage of APPwt and APPswe and Aβ production, and the Golgi as the major processing site for APPswe, findings relevant to understand the molecular basis of Alzheimer's disease.</p>","PeriodicalId":23207,"journal":{"name":"Traffic","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140289085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}