Searching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cells

Abstract Background Short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) is a ubiquitously expressed mitochondrial enzyme with a role in the degradation of fatty acids. Because the protein also is a negative regulator of insulin secretion in pancreatic β-cells, inactivating mutations in the SCHAD gen...

Full description

Saved in:
Bibliographic Details
Main Authors: Kelly Velasco, Janniche Torsvik, Johanna L. St-Louis, Sarah Baghestani, Jonas S. G. Silvander, Rohit N. Kulkarni, Diana M. Toivola, Anders Molven
Format: Article
Language:English
Published: BMC 2025-06-01
Series:BMC Molecular and Cell Biology
Subjects:
Online Access:https://doi.org/10.1186/s12860-025-00544-w
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850224179805159424
author Kelly Velasco
Janniche Torsvik
Johanna L. St-Louis
Sarah Baghestani
Jonas S. G. Silvander
Rohit N. Kulkarni
Diana M. Toivola
Anders Molven
author_facet Kelly Velasco
Janniche Torsvik
Johanna L. St-Louis
Sarah Baghestani
Jonas S. G. Silvander
Rohit N. Kulkarni
Diana M. Toivola
Anders Molven
author_sort Kelly Velasco
collection DOAJ
description Abstract Background Short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) is a ubiquitously expressed mitochondrial enzyme with a role in the degradation of fatty acids. Because the protein also is a negative regulator of insulin secretion in pancreatic β-cells, inactivating mutations in the SCHAD gene (HADH) cause congenital hyperinsulinism of infancy (CHI) and severe hypoglycemia. Here we sought to identify novel interaction partners of SCHAD that might be particularly relevant for the endocrine pancreas. Results Employing the SCHAD protein as bait, we performed yeast 2-hybrid screening of a cDNA library made from human islets of Langerhans. Surprisingly, the screening revealed the intermediate filament protein keratin 8 (K8) as a putative interaction partner of SCHAD with very high confidence. Previous reports have linked K8 to glucose homeostasis, and we confirmed the SCHAD interaction by co-immunoprecipitation in HEK293 cells. SCHAD and K8 expression were then characterized in the human β-cell model EndoC-βH1. By using proximity ligation assay, we demonstrated that stimulating the cells with a high level of glucose triggered a transient increase in the interaction. However, when studying knockout mice, we found that the loss of either K8 or SCHAD did not change the expression level of the other interaction partner. Still, when K8 knockout mice were challenged with a ketogenic diet, upregulation of SCHAD expression was blunted compared to the upregulation observed in wildtype littermates. Conclusions We propose that the SCHAD protein interacts with K8 in a way that might be relevant for proper functioning of the pancreatic β-cell. Whether the SCHAD-K8 interaction influences the phenotype of CHI remains to be demonstrated.
format Article
id doaj-art-191e7317cb234f21b91dc2d3281db458
institution OA Journals
issn 2661-8850
language English
publishDate 2025-06-01
publisher BMC
record_format Article
series BMC Molecular and Cell Biology
spelling doaj-art-191e7317cb234f21b91dc2d3281db4582025-08-20T02:05:42ZengBMCBMC Molecular and Cell Biology2661-88502025-06-0126111510.1186/s12860-025-00544-wSearching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cellsKelly Velasco0Janniche Torsvik1Johanna L. St-Louis2Sarah Baghestani3Jonas S. G. Silvander4Rohit N. Kulkarni5Diana M. Toivola6Anders Molven7Gade Laboratory for Pathology, Department of Clinical Medicine, University of BergenGade Laboratory for Pathology, Department of Clinical Medicine, University of BergenGade Laboratory for Pathology, Department of Clinical Medicine, University of BergenCell Biology, Faculty of Science and Engineering, Åbo Akademi UniversityCell Biology, Faculty of Science and Engineering, Åbo Akademi UniversityIslet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical SchoolCell Biology, Faculty of Science and Engineering, Åbo Akademi UniversityGade Laboratory for Pathology, Department of Clinical Medicine, University of BergenAbstract Background Short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) is a ubiquitously expressed mitochondrial enzyme with a role in the degradation of fatty acids. Because the protein also is a negative regulator of insulin secretion in pancreatic β-cells, inactivating mutations in the SCHAD gene (HADH) cause congenital hyperinsulinism of infancy (CHI) and severe hypoglycemia. Here we sought to identify novel interaction partners of SCHAD that might be particularly relevant for the endocrine pancreas. Results Employing the SCHAD protein as bait, we performed yeast 2-hybrid screening of a cDNA library made from human islets of Langerhans. Surprisingly, the screening revealed the intermediate filament protein keratin 8 (K8) as a putative interaction partner of SCHAD with very high confidence. Previous reports have linked K8 to glucose homeostasis, and we confirmed the SCHAD interaction by co-immunoprecipitation in HEK293 cells. SCHAD and K8 expression were then characterized in the human β-cell model EndoC-βH1. By using proximity ligation assay, we demonstrated that stimulating the cells with a high level of glucose triggered a transient increase in the interaction. However, when studying knockout mice, we found that the loss of either K8 or SCHAD did not change the expression level of the other interaction partner. Still, when K8 knockout mice were challenged with a ketogenic diet, upregulation of SCHAD expression was blunted compared to the upregulation observed in wildtype littermates. Conclusions We propose that the SCHAD protein interacts with K8 in a way that might be relevant for proper functioning of the pancreatic β-cell. Whether the SCHAD-K8 interaction influences the phenotype of CHI remains to be demonstrated.https://doi.org/10.1186/s12860-025-00544-wCongenital hyperinsulinism of infancyShort-chain 3-hydroxyacyl-CoA dehydrogenaseSCHADHADHIntermediate filamentsKeratin 8
spellingShingle Kelly Velasco
Janniche Torsvik
Johanna L. St-Louis
Sarah Baghestani
Jonas S. G. Silvander
Rohit N. Kulkarni
Diana M. Toivola
Anders Molven
Searching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cells
BMC Molecular and Cell Biology
Congenital hyperinsulinism of infancy
Short-chain 3-hydroxyacyl-CoA dehydrogenase
SCHAD
HADH
Intermediate filaments
Keratin 8
title Searching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cells
title_full Searching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cells
title_fullStr Searching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cells
title_full_unstemmed Searching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cells
title_short Searching for protein partners of short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) reveals keratin 8 as a novel candidate for interaction in pancreatic β-cells
title_sort searching for protein partners of short chain 3 hydroxyacyl coa dehydrogenase schad reveals keratin 8 as a novel candidate for interaction in pancreatic β cells
topic Congenital hyperinsulinism of infancy
Short-chain 3-hydroxyacyl-CoA dehydrogenase
SCHAD
HADH
Intermediate filaments
Keratin 8
url https://doi.org/10.1186/s12860-025-00544-w
work_keys_str_mv AT kellyvelasco searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells
AT jannichetorsvik searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells
AT johannalstlouis searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells
AT sarahbaghestani searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells
AT jonassgsilvander searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells
AT rohitnkulkarni searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells
AT dianamtoivola searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells
AT andersmolven searchingforproteinpartnersofshortchain3hydroxyacylcoadehydrogenaseschadrevealskeratin8asanovelcandidateforinteractioninpancreaticbcells