2024 Nobel Prize in Physiology or Medicine Announced!

Credit:https://www.nobelprize.org/prizes/medicine

On October 7, 2024, the Karolinska Institute in Sweden announced that American scientists Victor Ambros and Gary Ruvkun have been awarded the 2024 Nobel Prize in Physiology or Medicine. This is the highest honor in physiology and medicine, and an accolade many researchers strive for throughout their careers.

Victor Ambros and Gary Ruvkun were honored for their discovery of microRNA and its regulatory mechanisms, a breakthrough that has had a profound impact on biology and medicine, particularly in understanding complex genetic networks and disease mechanisms.

How was microRNA discovered?

At the time of their discovery, researchers already knew that DNA could transcribe RNA from one of its strands, and mRNA would carry this genetic information from DNA to ribosomes in the cytoplasm to direct protein synthesis, a process known as gene expression. However, scientists were puzzled by the fact that cells in different parts of the body, despite having the same DNA, could express genes differently. This raised the question: how could the same DNA lead to the formation of heart cells in one case and red blood cells in another? Solving this mystery was key to advancing human biology.

In 1993, after years of research, Victor Ambros’team made a breakthrough while studying Caenorhabditis elegans. They discovered that two genes, lin-4 and lin-14, were involved in regulating its development. Ambros’team found that lin-4 encoded an RNA molecule only 22 nucleotides long. Despite its small size, this RNA molecule played a critical role in the development of C. elegans. By partially binding to lin-14 mRNA through complementary sequences, this small RNA inhibited lin-14 gene expression, ensuring the organism developed at the right pace. This 22-nucleotide RNA, produced by lin-4, became the first identified microRNA in history.

Meanwhile, Gary Ruvkun further demonstrated how lin-4 inhibited lin-14’s expression by binding to the 3' untranslated region of lin-14 mRNA. Ruvkun’s experiments revealed that lin-14 mRNA levels did not decrease after lin-4 expression. This indicated that lin-4 did not prevent lin-14 expression by degrading its mRNA but rather by suppressing its translation. This provided further evidence of microRNA’s regulatory role.

The discovery of microRNA made waves in the field of biology. As research continued, in 2000, Ruvkun discovered another microRNA, let-7, which was found to be widespread across many species, from C. elegans to humans.

The discovery also led to a reevaluation of introns, previously thought to be useless. It turned out that introns play a key role in producing microRNA. This finding deepened researchers’ understanding of genetic regulation and genetic engineering.

Since then, over 2,000 microRNAs have been identified in humans, and the number continues to grow. However, some researchers have used this discovery as a basis for publishing low-quality papers, which hinders progress in the field.

RNA and the Nobel Prize

In recent years, RNA research has earned the Nobel Prize in Physiology or Medicine several times. With RNA research repeatedly recognized at the highest levels, it’s exciting to see what future discoveries may yet earn this prestigious honor.