Transcribing β-cell mitochondria in health and disease

Background

The recent genome-wide association studies (GWAS) of Type 2 Diabetes (T2D) have identified the pancreatic β-cell as the culprit in the pathogenesis of the disease. Mitochondrial metabolism plays a crucial role in the processes controlling release of insulin and β-cell mass. This notion implies that mechanisms controlling mitochondrial function have the potential to play a decisive pathogenetic role in T2D.

Scope of the review

This article reviews studies demonstrating that there is indeed mitochondrial dysfunction in islets in T2D, and that GWAS have identified a variant in the gene encoding transcription factor B1 mitochondrial (TFB1M), predisposing to T2D due to mitochondrial dysfunction and impaired insulin secretion. Mechanistic studies of the nature of this pathogenetic link, as well as of other mitochondrial transcription factors, are described.

Major conclusions

Based on this, it is argued that transcription and translation in mitochondria are critical processes determining mitochondrial function in β-cells in health and disease.

Data on cytochrome c oxidase assembly in mice and human fibroblasts or tissues induced by SURF1 defect

This paper describes data related to a research article entitled “Tissue- and species-specific differences in cytochrome c oxidase assembly induced by SURF1 defects” [1]. This paper includes data of the quantitative analysis of individual forms of respiratory chain complexes I, III and IV present in SURF1 knockout (SURF1^−/−) and control (SURF1^+/+) mouse fibroblasts and tissues and in fibroblasts of human control and patients with SURF1 gene mutation. Also it includes data demonstrating response of complex IV, cytochrome c oxidase (COX), to reversible inhibition of mitochondrial translation in SURF1^−/− mouse and SURF1 patient fibroblast cell lines.