All cells contain ribosomes, cellular organelles that are integral to the production of proteins in the body. In this article we look in more detail at the functions ribosomes perform and their impact on human health.
What are ribosomes?
Ribosomes are essentially molecular machines that convert amino acids into proteins in a process called translation. There are 20 distinct amino acids which form the building blocks for every type of protein generated by the human body.
In the translation process, mRNA relays a detailed set of genetic instructions to ribosomes. These instructions are written in codons, three-letter sequences of nucleotides. This code tells the ribosome which amino acids to use and in what sequence.
Each codon corresponds with a particular amino acid, or else relays a stop signal. The translation process all takes place within the ribosome, which functions as a sort of molecular protein synthesis factory.
Who discovered the ribosome?
Romanian cell biologist George Emil Palade discovered the ribosome. He received the Nobel Prize in 1974 for this groundbreaking contribution to science. In 2009, Ada Yonath, Venkatraman Ramakrishnan, and Tom Steitz received the Nobel Prize for Chemistry for identifying the ribosome’s complex structure.
How do ribosomes affect human health?
Proteins play many critical roles within the human body. We simply could not live without them. They come in a variety of forms, including: antibodies, messenger proteins, enzymes, transport proteins, structural components, and storage proteins.
If a cell did not contain ribosomes, it would not be able to produce proteins. Without proteins, an organism could not survive. Our bodies need proteins to maintain cellular structure, create hormones, and repair cellular damage. Proteins are integral to the cell-division and reproductive processes.
What are ribosomopathies?
Ribosomopathies are genetic defects that affect ribosome biogenesis. Scientists attribute many ribosomopathies to inherited gene mutations. Ribosomopathies can cause a range of symptoms, including: blood disorders; malformations of the face, limbs, and organs; eye defect; an increased risk of cancer; and impaired growth.
Diamond Blackfan Anemia is the most well-known form of ribosomopathy.
The most well-known form of ribosomopathy is Diamond Blackfan Anemia. First identified in 1938, and formerly known as Congenital Hypoplastic Anemia, this disease causes bone marrow failure.
Diamond Blackfan Anemia is a blood disorder. Bone marrow is essential in the production of healthy red blood cells. People with this disorder become severely anemic.
Red blood cells play a key role in delivering oxygen to cells all around the body. If there is a shortage of red blood cells, this can cause a range of symptoms, including: pallor; drowsiness; rapid heartbeat; heart murmurs; slowed growth; facial abnormalities; abnormalities of the hands, particularly the thumbs; kidney defects; and delayed puberty.
Diamond Blackfan Anemia is a rare disease, with approximately 25-35 new cases reported annually in the United States and Canada. It affects males and females equally and is hereditary. People with Diamond Blackfan Anemia have a 50 percent chance of passing the disease on to each of their children.
Is there a cure for ribosomopathies?
Therapies vary from disease to disease. The administration of steroids has been found to have a positive impact on 80 percent of people with Diamond Blackfan Anemia. Specialists administer blood transfusions to some people with Diamond Blackfan Anemia to boost their red blood cell count.
In some cases, doctors have cured Diamond Blackfan Anemia by performing bone marrow transplants. Stem cell therapies have also cured people with other ribosomopathies, including dyskeratosis congenita. However, specialists reserve transplants for the most serious cases due to the high risk of fatal, post-transplant pulmonary complications.
There may be a connection between ribosomes and cancer.
Scientists have long understood the importance of ribosomes in protein synthesis. Recent studies reveal that ribosomes could play a bigger role in the evolution of cancer than experts previously supposed. In addition to their well-documented function in protein production, ribosomes may pay a critical role in gene expression control.
Growing evidence indicates the existence of specialized ribosomes, each with its own unique composition and specific function. If congenital abnormalities occur in either ribosome biogenesis or function, scientists note increased cancer incidence.
Cancer is a generic term for hundreds of individual diseases that share the same key characteristics. Classic traits exhibited by cancer cells include immunity to growth suppressors and replicative immortality. These mutated cells grow unchecked, leading to the development of a tumor.
All cancer types share the same common feature: uncontrolled cell proliferation. Uncontrolled cell proliferation occurs as a direct result of enhanced protein synthesis, and protein synthesis takes place within the ribosome. Clinical studies show that mutations or alterations in ribosomes can compromise production of normal ribosome proteins. This, in turn, may trigger cancer.
Scientists still have far to go in terms of research. However, they are learning about the functions performed by ribosomes, their impact in terms of human health and disease, and the link between abnormal ribosome function and the development of serious diseases like cancer.