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        When a Micro Discovery Leads to                                                                                          ulate transcription but can also activate translation. We have a deeper   developmental events. Genes Dev. 1987 Jun;1(4):398-414. doi:


        a Nobel Prize                             ®                                                                              understanding of the molecular mechanisms underlying this process.   4.   Bhaskaran M., Mohan M. MicroRNAs: history, biogenesis, and
                                                                                                                                                                                          10.1101/gad.1.4.398
                                                                                                                                 Given their vital roles in cell development and function, it is not sur-

                                                                                                                                 species. For instance, let-7, which is essential for larval development in
                                                                                                                                                                                          2014 Jul;51(4):759-74. doi: 10.1177/0300985813502820
        By Kreny Savaliya, Hunter Buescher and Ramaswamy Sharma, MS, PhD                                                         prising that they are evolutionarily conserved across a wide range of   their evolving role in animal development and disease. Vet Pathol.
                                                                                                                                 C. elegans, is also found in humans.                  5.   Lee R.C., Feinbaum R.L., Ambros V. “Nomination and Selection
            ir Alfred Nobel, a Swedish chemist credited with inventing explo-  Technology. The Horvitz laboratory used Ceanorhabditis elegans, a   Dysregulation of miRNAs is associated with many pathologies.   of Medicine Laureates.” NobelPrize.org, 2019. www.nobelprize.
            sives such as dynamite, blasting gelatin and ballistite, bequeathed   roundworm that is just a mm in length, as a model to determine how   Mutations in miRNA-coding genes have been associated with con-  org/nomination/medicine/
        Shis vast estate for recognizing distinguished, paradigm-shifting  cells develop. Horvitz, John Sulston and Martin Chalfie (all Nobel   ditions such as congenital hearing loss and skeletal abnormalities.  6.   The C. elegans heterochronic gene lin-4 encodes small RNAs with
        achievements that benefit humans in the fields of physics, chemistry,  laureates) had earlier characterized many heterochronic mutant C. ele-  Therefore, miRNAs are being scrutinized as targets for drug devel-  antisense complementarity to lin-14. Cell. 1993 Dec 3;75(5):843-
        physiology or medicine, economic sciences, literature and peace. These  gans worms, so-called because their temporal pattern of cell develop-  opment as well as therapeutic agents themselves. For example, inhibi-  54. doi: 10.1016/0092-8674(93)90529-y
        awards, known as Nobel Prizes, come with a diploma, a medal and a  ment was disturbed by those mutations, when they worked in Sydney   tors targeting miR-92a and miR-122 are under investigation for their  7.   O’Brien J., Hayder H., Zayed Y., Peng C. Overview of MicroR-
        cash prize of 11 million Swedish kronor, and are presented by the King   Brenner’s laboratory (also a Nobel laureate); one such heterochronic   potential benefits in treating cardiovascular diseases and hepatitis C,   NA Biogenesis, Mechanisms of Actions, and Circulation. Front
        of Sweden. Victor Ambros, a professor of molecular medicine at the   mutant was lin-4 (cell lineage abnormal-4) that was unable to lay eggs   respectively. Additionally, several miRNA candidates are currently   Endocrinol (Lausanne). 2018 Aug 3;9:402. doi: 10.3389/
        University of Massachusetts Chan Medical School, and Gary Ruvkun,   and displayed defects  in cell lineage. Ambros and Ruvkun further ana-  being tested for targeting cancer in clinical trials. Their role as bio-  fendo.2018.00402. https://doi.org/10.3389/fendo.2018.00402
        a professor of genetics at Harvard Medical School, were selected this  lyzed these heterochronic mutants in Horvitz’s laboratory. Ambros   markers is particularly compelling as they show remarkable promise  8.   “The Nobel Prize in Physiology or Medicine 2024.” NobelPrize.
        year to receive the Nobel Prize in Physiology and Medicine for their   discovered three more genes involved in heterochronicity – lin-14,   in identifying and tracking pathologies such as cancer, cardiovas-  org, 7 Oct. 2024. www.nobelprize.org/prizes/medicine/2024/
        discovery of a new type of RNA that plays a major role in regulating  lin-28 and lin-29. Both scientists continued working on these genes   cular diseases and neurological disorders. Because miRNAs can be   press-release/
        gene expression. Their findings have led to the discovery of a thousand   after they set up their own laboratories.      detected in liquid biopsies such as blood and urine, they represent  9.   Wang D. and Farhana A. “Biochemistry, RNA Structure.” PubMed,
        other microRNAs and a better understanding of the tight genetic con-  Ambros’s laboratory at Harvard University discovered that lin-4   a minimally invasive option for diagnosis, paving the way for easier   StatPearls Publishing, 2020, www.ncbi.nlm.nih.gov/books/
        trol exerted in our cells.                             inhibited lin-14 expression. Lin-14 expression is required for normal   patient monitoring.                                NBK558999/
           Our bodies consist of trillions of cells with the same genetic  early-stage development but its reduced expression is associated with   The landscape of RNA-based medicine continues to evolve with  10. Wightman B., Ha I., Ruvkun G. Posttranscriptional regulation of
        makeup; yet, our neurons behave and function differently from our   normal late-stage development. He cloned lin-4 and found that it gen-  the identification of other non-coding RNA classes, including long   the heterochronic gene lin-14 by lin-4 mediates temporal pattern
        muscle cells. This is due to a process known as specialization, which   erated an incredibly short RNA molecule that did not code for a protein.   non-coding RNAs (IncRNAs), circular RNAs (circRNAs), and small   formation in C. elegans. Cell. 1993 Dec 3;75(5):855-62. doi:
        involves gene regulation. Genes are made up of specific sequences of   Meanwhile, Ruvkun’s laboratory at Massachusetts General Hospital   interfering RNAs (siRNAs). A notable milestone in this domain was   10.1016/0092-8674(93)90530-4
        deoxyribonucleic acid (DNA); it was earlier thought that each gene   determined that the lin-14 gene was transcribed to generate mRNA   the FDA’s approval of Patisiran in 2018, the first siRNA-based drug
        is transcribed to form a specific sequence of ribonucleic acid (RNA),   at the later stages of development but did not make protein, i.e., lin-14   for treating hereditary transthyretin-mediated amyloidosis. While   Kreny Savaliya is a medical student at the University of the
        which, in turn, is translated to form a particular protein. Since all the   inhibition was post-transcriptional. They also discovered a sequence in   challenges such as off-target effects and the development of efficient   Incarnate Word School of Osteopathic Medicine, Class of 2028.
        cells in our body contain the same 22,300 protein-coding genes, only  the 3’Untranslated Region (3’ UTR) of lin-14 RNA that was comple-  delivery systems remain critical hurdles, the potential for RNA-  She is passionate about pursuing a career in pediatrics to positively
        those genes that are relevant towards its formation and function will   mentary to lin-4 RNA. Together, Ambros and Ruvkun established that   based diagnostics and treatments appears increasingly promising. No   impact children’s health. She is also dedicated to participating in
        be active in a given cell type; the remaining genes are “silenced.” Thus,   the short RNA transcribed by the lin-4 gene bound to the lin-14 RNA   wonder the Nobel committee is recognizing the pivotal discovery of   mission trips to provide medical care to underserved communities and
        the genes that are active in a neuron will be different from those in a   and prevented its translation to protein. This was a groundbreaking dis-  miRNA in medicine that has heralded a transformative shift in how   broaden her understanding of global health issues.
        muscle cell, thereby making it function differently from a muscle cell.  covery, as Ambros and Ruvkun were the first to demonstrate that short   we approach healthcare.
        Prior to the seminal discovery of Ambros and Ruvkun, it was thought   RNAs (called microRNA or miRNA) could regulate gene expression                                                  Hunter Buescher is a medical student at the University of the
        that certain proteins, called transcription factors, attach to DNA and  after DNA was transcribed to RNA. Their findings were published   References:                                Incarnate Word School of Osteopathic Medicine, Class of 2028.
        either promote or inhibit formation of proteins, thereby deciding  in 1993 in back-to-back articles in the journal Cell. However, it took   1.   “Alfred Nobel’s Will - Nobel Peace Prize.” Www.nobelpeaceprize.  His interests include preventative medicine and community
        which genes were active and were translated to synthesize proteins.  seven more years and the identification of another microRNA, let7, for   org, 30 Aug. 2021, www.nobelpeaceprize.org/nobel-peace-prize/  health.
           During the 1980’s, Ambros and Ruvkun worked together as post-  their discovery to be accepted by the scientific community. Many more   history/alfred-nobel-s-will
        doctoral fellows in the laboratory of Robert Horvitz, who received  microRNAs have been discovered since.                2.   Almeida M.I., Reis R.M., Calin G.A. MicroRNA history: discov-  Ramaswamy Sharma, MS, PhD, is a Professor of Histology
        the Nobel Prize in 2002 for his contribution towards the elucidation   We now know that miRNAs are non-coding RNAs, typically   ery, recent applications, and next frontiers. Mutat Res. 2011 Dec   and Pathology at the University of the Incarnate Word School of
        of programmed cell death during development. Interestingly, Ambros   around 22 nucleotides long, that mostly interact with the 3’ UTR of   1;717(1-2):1-8. doi: 10.1016/j.mrfmmm.2011.03.009   Osteopathic Medicine. He is interested in delineating the multiple
        had previously been mentored by David Baltimore, another Nobel   target mRNAs, resulting in their degradation and thereby, translation-  3.   Ambros V., Horvitz H.R. The lin-14 locus of Caenorhabditis   molecular and cellular roles of melatonin in maintaining our
        laureate, for his graduate research at the Massachusetts Institute of  al repression. Recent discoveries indicate that miRNAs not only reg-  elegans controls the time of expression of specific postembryonic   quality of life. Dr. Sharma serves on the BCMS Publications Committee.

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