The mitochondria are the cells’ powerhouses that convert energy locked in our food into a functional “energy currency” for the cells. They also have their own protein synthesis factories called ribosomes.
Ribosomes are key molecular machines, fundamental to all life on Earth. They decode the information carried by messenger RNAs (mRNAs) and translate it into proteins.
Because the mitochondria are responsible for energy production through oxidative phosphorylation (OXPHOS), cell types that depend on OXPHOS for a large part of their energy supply such as nerve, brain, heart, and muscle are particularly susceptible to mitochondrial malfunction.
The mitochondrial ribosome, or mitoribosome, is a protein complex that is active in mitochondria and functions as a riboprotein for translating mitochondrial mRNAs.
As the mitoribosome is responsible for the manufacture of proteins necessary for the electron transport chain, malfunctions in the mitoribosome can result in metabolic disease. In humans, disease particularly manifests in energy-reliant organs such as the heart, brain, and muscles. Particularly neurological disorders, and various cardiomyopathies
Studies show that fourteen genes essential to mitochondria were up-regulated after THz radiation exposure, including four nuclear genes encoding components of the mitochondrial ribosome (MRPL34, MRPL43, MRPL55, and MRPS24), otherwise known as Mitochondrial Ribosomal Proteins (mitoribosome).
Mammalian mitochondrial ribosomes translate 13 proteins encoded by mitochondrial genes, all of which play roles in the mitochondrial respiratory chain. After a long period of reconstruction, mitochondrial ribosomes are the most protein-rich ribosomes. Mitochondrial ribosomal proteins (MRPs) are encoded by nuclear genes, synthesized in the cytoplasm, and then, transported to the mitochondria to be assembled into mitochondrial ribosomes. MRPs play a role in mitochondrial oxidative phosphorylation (OXPHOS). The mitochondrial oxidative phosphorylation (OXPHOS) system is the final biochemical pathway in the production of ATP.
Moreover, they participate in the regulation of cell state as apoptosis-inducing factors. Abnormal expressions of MRPs will lead to mitochondrial metabolism disorders, cell dysfunction, etc. Many kinds of research have demonstrated the abnormal expression of MRPs in various tumors.
Most of the energy required for cell growth, differentiation, and development is met by the mitochondria in the form of ATP produced by the process of oxidative phosphorylation. Human mitochondrial DNA encodes a total of 13 proteins, all of which are essential for oxidative phosphorylation. The mRNAs for these proteins are translated on mitochondrial ribosomes.
Interference with their synthesis, either by deletion or mutation of the mitochondrial genes for these proteins and other components of the mitochondrial translation system, such as mitochondrial tRNAs, is known to cause different mitochondrial diseases of variable severity, including myopathies and sensorineural disorders such as blindness and deafness.