User:Trevorburnes/Mitochondrial ribosome

Citations / notes:

General overview of "mitoribosome"; quality secondary source

Genes in mitochondrial diseases, secondary

Primary source, but shows the structure of the mammalian mitoribosome.

Secondary source, review of mitoribosome structure when diseased/ healthy

Secondary source for plant mitoribosome

Lead
Add that it is fixed to the inside of the ribosome, also that the mitoribosomal proteins are encoded in the cell's nucleus by the cell's cystolic ribosomes, while the rRNAs are made in the mitochondria/by the mitochondria's genome.

Comparison to Other Ribosomes
Like the mitochondria itself, mitochondrial ribosomes are descended from bacterial ribosomes. However, there has been significant divergence between the two as mitochondria evolved, leading to differences in in configuration and function. In configuration, the mitoribosome includes additional proteins in both its large and small subunits. In function, mitoribosomes are much more limited in the proteins they translate, only producing a few proteins used mostly in the mitochondrial membrane. Below is a table showing some properties of different ribosomes:

Diseases
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 muscle. Disease either originates from mutations in mitochondrial rRNA or genes encoding the mitoribosomal proteins. In the case of mitoribosomal protein mutation, heredity of disease follows Mendelian inheritance as these proteins are encoded in the nucleus. On the other hand, because mitochondrial rRNA is encoded in the mitochondria, mutations in rRNA are maternally inherited. Examples of diseases in humans caused by these mutations include Leigh syndrome, deafness, neurological disorders, and various cardiomyopathies. In plants, mutation in mitoribosomal proteins can result in stunted size and distorted leaf growth.