Page last updated: 2024-10-24

inner mitochondrial membrane protein complex

Definition

Target type: cellularcomponent

Any protein complex that is part of the inner mitochondrial membrane. [GOC:dos]

The inner mitochondrial membrane (IMM) protein complex is a highly intricate and functionally diverse entity, responsible for crucial metabolic processes that sustain cellular life. Its composition encompasses a wide array of proteins, each playing a distinct role in the intricate machinery of energy production, cellular signaling, and maintaining mitochondrial integrity.

The IMM protein complex is embedded within the inner membrane, a selectively permeable barrier that encloses the mitochondrial matrix. This membrane is a dynamic structure, characterized by its high protein content and specialized lipid composition. The proteins within the IMM complex are organized into distinct functional modules, each contributing to the overall efficiency and regulation of mitochondrial processes.

One prominent feature of the IMM complex is the electron transport chain (ETC), a series of protein complexes that facilitate the transfer of electrons from reduced substrates to molecular oxygen. This process drives the generation of a proton gradient across the IMM, ultimately powering ATP synthesis through oxidative phosphorylation. The ETC is composed of four major complexes: Complex I (NADH dehydrogenase), Complex II (succinate dehydrogenase), Complex III (cytochrome bc1 complex), and Complex IV (cytochrome c oxidase).

In addition to the ETC, the IMM complex houses other vital components that contribute to mitochondrial function. These include:

* **ATP synthase:** A rotary motor complex that utilizes the proton gradient generated by the ETC to synthesize ATP, the primary energy currency of cells.
* **Mitochondrial carriers:** Transmembrane proteins responsible for transporting essential metabolites, such as pyruvate, ADP, and ATP, across the IMM.
* **Mitochondrial import machinery:** A complex set of proteins that mediate the translocation of newly synthesized proteins from the cytoplasm into the mitochondrial matrix and intermembrane space.
* **Mitochondrial fission and fusion machinery:** Proteins that regulate the dynamic changes in mitochondrial morphology, ensuring proper distribution and function of mitochondria within the cell.

The IMM protein complex is a highly dynamic and responsive structure, constantly adapting to changing cellular demands. Its intricate organization and diverse functions underscore its critical role in maintaining cellular homeostasis and energy metabolism. This complex network of proteins orchestrates a symphony of molecular events, ensuring the efficient and regulated operation of the mitochondrial power plant.'
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Proteins (1)

ProteinDefinitionTaxonomy
Mitochondrial pyruvate carrier 2A brain protein 44 that is encoded in the genome of human. [PRO:DNx, UniProtKB:O95563]Homo sapiens (human)

Compounds (1)

CompoundDefinitionClassesRoles
msdc-0160MSDC-0160: an mTOT (mitochondrial target of thiazolidinediones) modulator for insulin sensitization; structure in first sourcearomatic ether