Mitokondrinin İşlevsel Rolleri

Öz

Mitokondri, ATP üretimi, kalsiyum homeostazisi, hücre proliferasyonu, programlanmış hücre ölümü ve amino asitlerin, nükleotidlerin ve lipitlerin sentezi dahil olmak üzere çeşitli hücresel metabolik süreçlerde rol oynar. Her mitokondrinin kendi genomu olmasına rağmen çoğu mitokondriyal protein nükleer DNA tarafından kodlanır. Çoğu ökaryotik hücrede bulunan hücre altı organelleri olan mitokondri, trikarboksilik asit döngüsü (TCA döngüsü),oksidatif fosforilasyon (OXPHOS), amino asit metabolizması ve yağ asidi oksidasyonu dahil olmak üzere çok sayıda metabolik ağ işleminden sorumludur. Bunlar arasında mitokondrinin en önemli fizyolojik işlevi besinleri oksitleyerek ATP üretmektir. Adenozin 5′-trifosfat (ATP) üretimine katılmak için mitokondri, serbest radikallerin üretildiği bu metabolik ağ işlemleriyle etkileşime giren karmaşık bir sistem kullanır. Genel olarak, mitokondriyal reaktif oksijen türleri (ROS) üretimi esas olarak mitokondriyal iç membran üzerinde yer alan elektron taşıma zinciri bölgesinde meydana gelir ve elektronların kompleks I ve kompleks III'ten sızması oksijen tüketimine ve süperoksit oluşumuna yol açar. Mitokondriyal redoks homeostazisi, mitokondriyal fonksiyonun ve hücre kaderinin belirlenmesinin temelini oluşturan ROS üretimi ve süpürme arasındaki dengeyi ifade eder. Bu derleme, mitokondrinin işlevsel rollerini özetlemektedir.

Anahtar Kelimeler

• ATP
• Mitokondri
• Mitokondriyal işlev
• ROS
• TCA döngüsü

Functional Roles of Mitochondria

Abstract

Mitochondria play a role in various cellular metabolic processes, including ATP production, calcium homeostasis, cell proliferation, programmed cell death, and the synthesis of amino acids, nucleotides, and lipids. Although each mitochondrion has its own genome, most mitochondrial proteins are encoded by nuclear DNA. Mitochondria, which are subcellular organelles found in most eukaryotic cells, are responsible for numerous metabolic network processes, including the tricarboxylic acid cycle (TCA cycle), oxidative phosphorylation (OXPHOS), amino acid metabolism, and fatty acid oxidation. Among these, the most important physiological function of mitochondria is to produce ATP by oxidizing nutrients. To participate in the production of adenosine 5′-triphosphate (ATP), mitochondria use a complex system that interacts with these metabolic network processes, where free radicals are produced. In general, mitochondrial reactive oxygen species (ROS) production occurs mainly at the electron transport chain site located on the mitochondrial inner membrane, and leakage of electrons from complex I and complex III leads to oxygen consumption and superoxide formation. Mitochondrial redox homeostasis refers to the balance between ROS production and scavenging that underlies mitochondrial function and cell fate determination. This review summarizes functional roles of mitochondria.

Keywords

• ATP
• Mitochondria
• Mitochondrial function
• ROS
• TCA cycle

Kaynakça

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