Watson, Crick, and Franklin’s DNA Story: Central dogma and RNA (2)

Watson, Crick and Franklin

Watson and Crick are pivotal scientists in understanding biological pathways. While they are globally renowned, Franklin, who has recently gained recognition, also made a significant contribution to this groundbreaking discovery. Franklin studied the internal structure of DNA using X-ray diffraction and gathered essential data. Notably, the famous “Photo 51” she captured was a critical image that provided strong evidence of DNA’s double-helix structure.

This data is the crucial results to understand DNA structure. This is where a breach of research ethics becomes apparent. Maurice Wilkins, Franklin’s colleague, showed her data to James Watson and Francis Crick without her permission. This data became the critical foundation for Watson and Crick’s 1953 publication of the DNA double-helix model. However, Franklin did not receive proper recognition for her research, which was fundamental to the development of this model. This story remains a case where women’s rights were not properly acknowledged, and research ethics were not clearly established. As a result of this incident, it has led researchers today to adhere to stricter standards in conducting their own studies.

Watson and Crick: DNA structure and central dogma

Although Crick and Watson’s reputation remains controversial, their discovery was remarkable and can be considered the beginning of modern life sciences. The two almost perfectly deciphered the structure of DNA and uncovered key facts, including that DNA consists of two paired strands, the distance between the pairs is 10 Å, and guanine pairs with cytosine while adenine pairs with thymine.

https://www.nature.com/articles/171737a0

In fact, the controversy surrounding their reputation might be somewhat exaggerated, as the two explicitly acknowledged in their paper that Franklin’s experimental results were helpful to their work. They wrote: “We have also been stimulated by a knowledge of the general nature of the unpublished experimental results and ideas of Dr. M. H. F. Wilkins, Dr. R. E. Franklin and their co-workers at King’s College, London.“

(X-ray photographs that merely provided inspiration and were not directly cited in the paper are typically not sufficient to warrant authorship. Acknowledgments, as seen in this case, are the standard practice. Franklin did not receive the Nobel Prize because she passed away before the award was given. This is due to the Nobel Prize being awarded only to living individuals. As a humorous remark, it is often said that the hardest part of winning a Nobel Prize is simply living long enough.)

The achievements of Crick continue to stand as nearly perfect representations of DNA structure, which they accurately detailed in their 1953 Nature paper. Additionally, they discovered the concept of the central dogma, which describes the flow of genetic information from DNA to RNA to protein. “To briefly summarize this paper: DNA replicates through self-division. DNA produces RNA, and RNA produces protein. An exception occurs when RNA is reverse-transcribed into DNA, which is typically observed in RNA viruses.”

https://www.nature.com/articles/227561a0

Since the two papers are not long, I highly recommend reading them.

Does all RNA code for proteins?

Here, RNA is actually more complex. There are numerous different forms of RNA, and not all RNA codes for proteins. This includes tRNA and rRNA, with only mRNA containing the information for proteins. One of the most important types of RNA currently is miRNA, which recently earned a Nobel Prize for its discoverer.

There are numerous other types of RNA, such as miRNA and siRNA. These RNAs are produced by DNA and are made from introns, which do not contain the genetic information from the DNA. This RNA is used in a wide range of biotechnologies, starting from the well-known COVID vaccines to aptamers, which can bind to specific proteins. It is also utilized to create molecules similar to antibodies, but made from DNA or RNA instead of proteins.

I believe this is one of the fields we will see more of in the future.

mRNA and qPCR: Understanding Gene Expression (3)