The Nobel Prize is one of the most prestigious honors a scientist can receive, awarded annually to individuals whose work profoundly benefits humanity. This year, the Nobel Prize in Physiology or Medicine recognizes an achievement that has transformed our understanding of biology and opened new possibilities for medical advancements.
The Nobel Prize in Physiology or Medicine: Ambros, Ruvkun
“for the discovery of microRNA and its role in post-transcriptional gene regulation”
Photo Credit: Niklas Elmehed
Every cell in the human body contains a complete copy of the human genome — all 23 pairs of chromosomes and roughly 20,000 genes. Yet, despite this identical genetic blueprint, cells develop into specialized types like skin cells, muscle cells, or neurons. This process, called cell differentiation, occurs through the activation of specific genes to express traits necessary for specialized functions. Until recently, the mechanisms driving this complex process remained largely mysterious. Professors Victor Ambros and Gary Ruvkun changed that by discovering microRNA (miRNA) and revealing its critical role in gene regulation.
Image credit: BioRender
To understand how microRNA works, it’s essential to revisit the Central Dogma of molecular biology, a concept familiar from high school biology. The Central Dogma explains how genetic instructions in DNA are used to create proteins, the molecular machinery that drives life.
Image credit: BioRender
Two essential steps to make a protein from DNA:
- Transcription: DNA is “read” to produce a molecule called RNA, which carries genetic instructions in a slightly different format.
- Translation: RNA is then “read” to build proteins, which are made of entirely different building blocks than DNA and RNA. This step is akin to translating a message into a new language.
Proteins perform a vast range of functions, from forming muscle fibers to regulating blood pressure. They are the workhorses of life, directing nearly every process in living organisms.
Drs. Ambros and Ruvkun discovered that a special type of RNA, called microRNA (miRNA), plays a critical role in regulating gene expression. Here’s how it works:
Image credit: BioRender
RNA produced during transcription is typically long, like a highway. MicroRNA, in contrast, is extremely short — comparable to the width of a driveway. Because RNA is single-stranded, microRNA can bind to complementary sequences on long RNA strands, forming a double-stranded structure.
When this happens, the translation process is disrupted. The machinery that reads RNA to create proteins is blocked, preventing the production of proteins. In some cases, the binding of microRNA even causes the long RNA to break down entirely, stopping protein production immediately. This ability to control protein production is crucial for regulating which traits are expressed in cells. MicroRNA acts as a molecular “switch,” fine-tuning the cellular processes that shape life.
Image credit: BioRender
The discovery of microRNA has revolutionized biology and opened new possibilities in medicine. Scientists are now exploring how microRNAs could be used to treat genetic diseases, such as cancer, Alzheimer’s, and spinal disc degeneration. By introducing or modifying microRNAs, it may be possible to “turn off” harmful genes and prevent the production of disease-causing proteins.
Image credit: BioRender
Drs. Ambros and Ruvkun have illuminated a new path for biological research, unlocking potential therapies that could transform how we treat some of the most challenging diseases. Their discovery is not just a milestone in science but a beacon of hope for countless patients worldwide.
