{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T11:11:01Z","timestamp":1782990661746,"version":"3.54.5"},"reference-count":49,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,15]],"date-time":"2021-10-15T00:00:00Z","timestamp":1634256000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Epidemiological studies support a connection between the two common disorders, type-2 diabetes and Alzheimer\u2019s disease. Both conditions have local amyloid formation in their pathogenesis, and cross-seeding between islet amyloid polypeptide (IAPP) and amyloid \u03b2 (A\u03b2) could constitute the link. The bimolecular fluorescence complementation (BiFC) assay was used to investigate the occurrence of heterologous interactions between IAPP and A\u03b2 and to compare the potential toxic effects of IAPP\/A\u03b2, IAPP\/IAPP, and A\u03b2\/A\u03b2 expression in living cells. Microscopy was used to confirm the fluorescence and determine the lysosomal, mitochondrial areas and mitochondrial membrane potential, and a FACS analysis was used to determine ROS production and the role for autophagy. Drosophila melanogaster expressing IAPP and A\u03b2 was used to study their co-deposition and effects on longevity. We showed that the co-expression of IAPP and A\u03b2 resulted in fluorophore reconstitution to the same extent as determined for homologous IAPP\/IAPP or A\u03b2\/A\u03b2 expression. The BiFC(+)\/BiFC(\u2212) ratio of lysosomal area calculations increased in transfected cells independent of the vector combinations, while only A\u03b2\/A\u03b2 expression increased mitochondrial membrane potential. Expression combinations containing A\u03b2 were necessary for the formation of a congophilic amyloid. In Drosophila melanogaster expressing IAPP\/A\u03b2, co-deposition of the amyloid-forming peptides caused reduced longevity. The BiFC results confirmed a heterologous interaction between IAPP and A\u03b2, while co-deposits in the brain of Drosophila suggest mixed amyloid aggregates.<\/jats:p>","DOI":"10.3390\/ijms222011153","type":"journal-article","created":{"date-parts":[[2021,10,17]],"date-time":"2021-10-17T23:05:47Z","timestamp":1634511947000},"page":"11153","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["The Amyloid Forming Peptides Islet Amyloid Polypeptide and Amyloid \u03b2 Interact at the Molecular Level"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7899-9112","authenticated-orcid":false,"given":"Ye","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Medical Cell Biology, Uppsala University, 75123 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gunilla T.","family":"Westermark","sequence":"additional","affiliation":[{"name":"Department of Medical Cell Biology, Uppsala University, 75123 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1080\/13506129.2020.1835263","article-title":"Amyloid nomenclature 2020: Update and recommendations by the International Society of Amyloidosis (ISA) nomenclature committee","volume":"27","author":"Benson","year":"2020","journal-title":"Amyloid"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1517\/03009734000000014","article-title":"Quantitative studies on amyloid in the islets of Langerhans","volume":"77","author":"Westermark","year":"1972","journal-title":"Ups. 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