{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/125773"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/125773","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Live cell imaging of protein trafficking: Dynamics and functional insights","abstract":"Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-08-01","abstract_html":"Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-08-01","abstract_has_math":false,"creators":["Mehta, Kritika"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Biochemistry","degree_department":null,"school":null,"contributors":["Zhang, Kai","Fratti, Rutillo A","Tsai, Nien-Pe","Stadtmueller, Beth M"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-07-10","date_published":"2024-07-10","updated_at":"2026-07-22T22:25:02Z","subjects":["Activity-regulated Cytoskeleton-associated Protein","Phospholipids","Virus-like Capsid","Fluorescence Imaging","Super Resolution Imaging","Minflux"],"languages":["en","eng"],"rights":["© 2024 Kritika Mehta"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/125773","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Zhang, Kai","Fratti, Rutillo A","Tsai, Nien-Pe","Stadtmueller, Beth M"]},{"key":"dc:creator","label":"Author","values":["Mehta, Kritika"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2024-07-10","2024-08"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biochemistry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Activity-regulated Cytoskeleton-associated Protein","Phospholipids","Virus-like Capsid","Fluorescence Imaging","Super Resolution Imaging","Minflux"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["© 2024 Kritika Mehta"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/125773"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-08-01","The student, Kritika Mehta, accepted the attached license on 2024-07-01 at 17:06.","The student, Kritika Mehta, submitted this Dissertation for approval on 2024-07-01 at 17:22.","This Dissertation was approved for publication on 2024-07-10 at 15:04.","DSpace SAF Submission Ingestion Package generated from Vireo submission #20914 on 2025-02-04 at 21:25:13","Activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) is an immediate early gene that plays a vital role in learning and memory. Arc protein has structural and functional properties similar to viral Group-specific antigen (Gag) protein and mediates the intercellular RNA transfer through virus-like capsids. However, the regulators and secretion pathway through which Arc capsids maneuver cargos are unclear. Here, we identified that phosphatidylinositol-3-phosphate (PI3P) mediates Arc capsid assembly and secretion through the endosomal-multivesicular body (MVB) pathway. Indeed, reconstituted Arc protein preferably binds to PI3P. In HEK293T cells, Arc forms puncta that colocalizes with FYVE, an endosomal PI3P marker, as well as Rab5 and CD63, early endosomal and MVB markers, respectively. Super-resolution imaging resolves Arc accumulates within the intraluminal vesicles of MVB. CRISPR double knockout of RalA and RalB, crucial GTPases for MVB biogenesis and exocytosis, severely reduces the Arc-mediated RNA transfer efficiency. RalA/B double knockdown in cultured rat cortical neurons increases the percentage of mature dendritic spines. Intake of extracellular vesicles purified from Arc-expressing wild-type, but not RalA/B double knock-down, cells in mouse cortical neurons reduce their surface GluA1 level. These results suggest that, unlike the Human Immunodeficiency Virus Gag, whose membrane targeting requires interaction with plasma-membrane-specific phosphatidyl inositol (4,5) bisphosphate (PI(4,5)P2), Arc capsids assemble at the endocytic membranes is mediated by PI3P. Understanding Arc’s secretion pathway helps gain insights into its role in intercellular cargo transfer and highlights the commonality and distinction of trafficking mechanisms between structurally resembled capsid proteins."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Live cell imaging of protein trafficking: Dynamics and functional insights"]}]}],"canonical_facts":{"dc:contributor":["Zhang, Kai","Fratti, Rutillo A","Tsai, Nien-Pe","Stadtmueller, Beth M"],"dc:creator":["Mehta, Kritika"],"dc:date":["2024-07-10","2024-08"],"dc:description":["Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-08-01","The student, Kritika Mehta, accepted the attached license on 2024-07-01 at 17:06.","The student, Kritika Mehta, submitted this Dissertation for approval on 2024-07-01 at 17:22.","This Dissertation was approved for publication on 2024-07-10 at 15:04.","DSpace SAF Submission Ingestion Package generated from Vireo submission #20914 on 2025-02-04 at 21:25:13","Activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) is an immediate early gene that plays a vital role in learning and memory. Arc protein has structural and functional properties similar to viral Group-specific antigen (Gag) protein and mediates the intercellular RNA transfer through virus-like capsids. However, the regulators and secretion pathway through which Arc capsids maneuver cargos are unclear. Here, we identified that phosphatidylinositol-3-phosphate (PI3P) mediates Arc capsid assembly and secretion through the endosomal-multivesicular body (MVB) pathway. Indeed, reconstituted Arc protein preferably binds to PI3P. In HEK293T cells, Arc forms puncta that colocalizes with FYVE, an endosomal PI3P marker, as well as Rab5 and CD63, early endosomal and MVB markers, respectively. Super-resolution imaging resolves Arc accumulates within the intraluminal vesicles of MVB. CRISPR double knockout of RalA and RalB, crucial GTPases for MVB biogenesis and exocytosis, severely reduces the Arc-mediated RNA transfer efficiency. RalA/B double knockdown in cultured rat cortical neurons increases the percentage of mature dendritic spines. Intake of extracellular vesicles purified from Arc-expressing wild-type, but not RalA/B double knock-down, cells in mouse cortical neurons reduce their surface GluA1 level. These results suggest that, unlike the Human Immunodeficiency Virus Gag, whose membrane targeting requires interaction with plasma-membrane-specific phosphatidyl inositol (4,5) bisphosphate (PI(4,5)P2), Arc capsids assemble at the endocytic membranes is mediated by PI3P. Understanding Arc’s secretion pathway helps gain insights into its role in intercellular cargo transfer and highlights the commonality and distinction of trafficking mechanisms between structurally resembled capsid proteins."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/125773"],"dc:language":["en","eng"],"dc:rights":["© 2024 Kritika Mehta"],"dc:subject":["Activity-regulated Cytoskeleton-associated Protein","Phospholipids","Virus-like Capsid","Fluorescence Imaging","Super Resolution Imaging","Minflux"],"dc:title":["Live cell imaging of protein trafficking: Dynamics and functional insights"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Biochemistry"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:02Z"}