Cytochrome c oxidase, the terminal protein of the electron transport chain, is composed in mammals of thirteen subunits, three encoded by mitochondrial DNA and ten by nuclear DNA. At least three of these nuclear subunits occur in more than one molecular form (isoforms), the products of separate genes. The proposed experiments will provide insights into the cellular function of these isoforms, which may be related to both ontogenetic development and cellular physiology. In addition, isoform expression has been implicated in human neuromuscular disease. This project will focus on three genes, already isolated, that encode two subunits, COX VIIa and COX VIIc. Subunit VIIa displays a heart/muscle-specific isoform (H) and an isoform (L) expressed in all tissue. A second subunit, VIIc, appears to have a single expressed form in all tissues.
The specific aims are to (1) characterize the core promoter interactions in the COX7AL, COX7AH, and COX7C genes; (2) determine the roles of promoter-distal sequences and factors in regulatory events that occur at the COX7AL, COX7AH, and COX7C core promoters by (a) identifying new regulatory sites that are core promoter distal, (b) identifying new regulatory sites and factors by application of yeast one-and two-hybrid technologies, and (c) determining the effect of new regulatory factor binding on events at the core promoter, and also the effect of distal DNA sequences per se; and (3) elucidating promoter function in cell development and differentiation. This project fits into the longer term objectives of deducing the role of the nuclear-encoded subunits and the mechanisms used to regulated oxidative function, and applying this knowledge to the study of nuclear genes in mitochondrial disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM048517-06
Application #
6018929
Study Section
Physical Biochemistry Study Section (PB)
Program Officer
Small, Judy A
Project Start
1993-02-01
Project End
2002-06-30
Budget Start
1999-07-01
Budget End
2000-06-30
Support Year
6
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Wayne State University
Department
Other Basic Sciences
Type
Schools of Medicine
DUNS #
City
Detroit
State
MI
Country
United States
Zip Code
48202
Sommer, Natascha; Hüttemann, Maik; Pak, Oleg et al. (2017) Mitochondrial Complex IV Subunit 4 Isoform 2 Is Essential for Acute Pulmonary Oxygen Sensing. Circ Res 121:424-438
Hüttemann, Maik; Klewer, Scott; Lee, Icksoo et al. (2012) Mice deleted for heart-type cytochrome c oxidase subunit 7a1 develop dilated cardiomyopathy. Mitochondrion 12:294-304
Hüttemann, Maik; Lee, Icksoo; Gao, Xiufeng et al. (2012) Cytochrome c oxidase subunit 4 isoform 2-knockout mice show reduced enzyme activity, airway hyporeactivity, and lung pathology. FASEB J 26:3916-30