SCO1

Protein SCO1 homolog, mitochondrial is a is_associated_with::protein that in humans is encoded by the SCO1 is_associated_with::gene. Mutations in both SCO1 and is_associated_with::SCO2 are associated with distinct clinical phenotypes as well as tissue-specific is_associated_with::cytochrome c oxidase deficiency. SCO1 localizes predominantly to blood vessels, whereas SCO2 is barely detectable. Expression of SCO2 is also much higher than that of SCO1 in is_associated_with::muscle tissue, while SCO1 is expressed at higher levels in is_associated_with::liver tissue than SCO2.

Function
Mammalian is_associated_with::cytochrome c oxidase (COX) catalyzes the transfer of reducing equivalents from is_associated_with::cytochrome c to molecular oxygen and pumps protons across the is_associated_with::inner mitochondrial membrane. In yeast, 2 related COX assembly genes, SCO1 and SCO2 (synthesis of cytochrome c oxidase), enable subunits 1 and 2 to be incorporated into the holoprotein. This gene is the human homolog to the yeast SCO1 gene.

Clinical relevance
Mutation in the SCO1 gene are a cause of mitochondrial complex IV deficiency also known as cytochrome c oxidase deficiency. This disorder affects the mitochondrial respiratory chain resulting in a variety of symptoms, ranging from isolated is_associated_with::myopathy to severe multisystem disease affecting several tissues and organs. A subset of patients also suffer from Leigh syndrome.

Model organisms
is_associated_with::Model organisms have been used in the study of SCO1 function. A conditional is_associated_with::knockout mouse line, called Sco1tm1a(KOMP)Wtsi was generated as part of the is_associated_with::International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists.

Male and female animals underwent a standardized is_associated_with::phenotypic screen to determine the effects of deletion. Twenty two tests were carried out on is_associated_with::mutant mice and two significant abnormalities were observed. No is_associated_with::homozygous is_associated_with::mutant embryos were identified during gestation, and therefore none survived until is_associated_with::weaning. The remaining tests were carried out on is_associated_with::heterozygous mutant adult mice; no additional significant abnormalities were observed in these animals.