Small GTPases ARF1 and ARF3 localize mainly to the Golgi apparatus, where they trigger formation of coated carrier vesicles. We previously showed that BIG2, a guanine nucleotide exchange factor specific for ARF1 and ARF3, localizes not only to the trans-Golgi network (TGN) but also to recycling endosomes, where it is involved in regulating the integrity of recycling endosomes. However, it is not yet clear whether ARF1 and ARF3 act downstream of BIG2 to ensure endosome integrity. In this study, we show that EGFP-tagged ARF1 and ARF3 localize to endosomal compartments containing endocytosed transferrin. We further demonstrate that simultaneous depletion of ARF1 and ARF3 induces tubulation of recycling endosomal compartments positive for transferrin receptor, Rab4, and Rab11, but does not significantly affect the integrity of the Golgi apparatus or early or late endosomes. Moreover, the simultaneous depletion of ARF1 and ARF3 suppresses recycling of transferrin but does not affect either its endocytosis or the retrograde transport of TGN38 from early/recycling endosomes to the TGN. In addition, depletion of ARF1 and ARF3 does not affect retrograde transport of CD4-furin from late endosomes to the TGN, or of endocytosed EGF from late endosomes to lysosomes. These results indicate that ARF1 and ARF3 are redundantly required for the integrity of recycling endosomes, and that they regulate transferrin recycling from endosomes to the plasma membrane, but not retrograde transport from endosomal compartments to the TGN.
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http://dx.doi.org/10.1247/csf.12015 | DOI Listing |
Genomics
January 2025
Department of Hematology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, PR China; Zhejiang Provincial Key Laboratory of Hematopoietic Malignancy, Zhejiang University, Hangzhou, Zhejiang, PR China; Zhejiang Provincial Clinical Research Center For Hematological Disorder, Hangzhou, Zhejiang, PR China; Zhejiang University Cancer Center, Hangzhou, Zhejiang, PR China. Electronic address:
Acute myeloid leukemia is a malignant hematologic disorder characterized by the excessive proliferation and accumulation of immature myeloid cells. This abnormality disrupts normal hematopoiesis, leading to symptoms such as anemia, increased susceptibility to infections and bleeding. ADP-ribosylation factors (ARFs) are critical in various cellular functions, including vesicular trafficking, membrane dynamics, cytoskeleton organization, signal transduction, endocytosis, exocytosis, and maintaining organelle integrity.
View Article and Find Full Text PDFOncol Lett
June 2024
Department of Breast Surgery, Xingtai People's Hospital, Xingtai, Hebei 054000, P.R. China.
Breast cancer (BC) is the most common type of cancer found in women. ADP-ribosylation factors (ARFs) are a group of small proteins that bind to GTP and are involved in controlling different cellular functions. The function and evolution of multiple ARFs in BC have remained to be fully elucidated, despite existing studies on this protein family in and other species.
View Article and Find Full Text PDFJ Biol Chem
June 2024
Laboratory of Intracellular Traffic & Oncology, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan. Electronic address:
Normal receptor tyrosine kinases (RTKs) need to reach the plasma membrane (PM) for ligand-induced activation, whereas its cancer-causing mutants can be activated before reaching the PM in organelles, such as the Golgi/trans-Golgi network (TGN). Inhibitors of protein export from the endoplasmic reticulum (ER), such as brefeldin A (BFA) and 2-methylcoprophilinamide (M-COPA), can suppress the activation of mutant RTKs in cancer cells, suggesting that RTK mutants cannot initiate signaling in the ER. BFA and M-COPA block the function of ADP-ribosylation factors (ARFs) that play a crucial role in ER-Golgi protein trafficking.
View Article and Find Full Text PDFHeliyon
April 2024
The First Affiliated Hospital of Xi'an Medical University, Xi'an, 710077, Shaanxi, China.
Background: ARF family proteins are a kind of small GTPases, which are involved in regulating a variety of basic functions of cells. In recent years, the role and molecular regulatory mechanisms of ARFs in tumor progression have received increasing attention, and research reports on most of their family members are increasing. However, research on the clinical and pathological relevance of ARF5 in cancer, especially in hepatocellular carcinoma, still needs to be improved.
View Article and Find Full Text PDFJ Cell Biol
July 2023
Institut für Biochemie, Freie Universität Berlin, Berlin, Germany.
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