Share to: share facebook share twitter share wa share telegram print page

RNA Tie Club

The RNA Tie Club was an informal scientific club, meant partly to be humorous,[1] of select scientists who were interested in how proteins were synthesised from genes, specifically the genetic code.[2] It was created by George Gamow upon a suggestion by James Watson in 1954[2] when the relationship between nucleic acids and amino acids in genetic information was unknown. The club consisted of 20 full members, each representing an amino acid, and four honorary members, representing the four nucleotides. The function of the club members was to think up possible solutions and share with the other members.

The first important document of the RNA Tie Club was Francis Crick's adaptor hypothesis in 1955. Experimental work on the hypothesis led to the discovery of transfer RNA, a molecule that carries the key to genetic code. Most of the theoretical groundwork and preliminary experiments on the genetic code were done by the club members within a decade. However, the specific code was discovered by Marshall Nirenberg, a non-member, who received Nobel Prize in Physiology or Medicine in 1968 for the discovery.

History

Background

In 1953, English biophysicist Francis Crick and American biologist James Watson, working together at the Cavendish Laboratory of the University of Cambridge, deduced the structure of DNA, the principal genetic material of organisms,[3] thought to link genetic information in DNA to proteins.[4] By 1954, it was becoming understood that the genetic information pathway involved DNA, RNA and proteins. However, the structure and nature of RNA were still a mystery (specific RNA molecules were not known until 1960[5]), especially how RNA is involved in protein synthesis.[6] Watson called this problem "the mystery of life" in his letter to Crick.[5]

Soviet-American physicist George Gamow at George Washington University suggested the first scheme for protein synthesis from DNA.[7][8] In early 1954, he spent several days at Woods Hole on Cape Cod with Crick, Watson and Sydney Brenner, discussing genetics.[2] Based on the Watson-Crick model, he proposed a "direct DNA template hypothesis" stating that proteins are synthesised directly from the double-stranded grooves of DNA.[9] The four bases of DNA were assumed to synthesise 20 different amino acids as triplets with overlapping nucleotide sequences.[10] He published the hypothesis in the 13 February 1954 issue of Nature, explaining:

It seems to me that such translation procedure can be easily established by considering the 'key-and-lock' relation between various amino-acids, and the rhomb-shaped 'holes' formed by various nucleotides in the deoxyribonucleic acid chain... One can speculate that free amino-acids from the surrounding medium get caught into the 'holes' of deoxyribonucleic acid molecules, and thus unite into the corresponding peptide chains.[11]

Foundation

In May 1954, Watson visited Gamow, who was on sabbatical at the University of California, Berkeley. While discussing Gamow's hypothesis, he suggested that they form a 20-member club to work out the genetic code.[2] Gamow instantly came up with the RNA Tie Club to "solve the riddle of the RNA structure and to understand how it built proteins", adding the motto "do or die; or don't try."[12]

The club thus consisted of 20 eminent scientists, each of whom corresponded to an amino acid, plus four honorary members (S. Brenner, VAL. F. Lipmann, A. Szent-Gyorgyi, and another individual), one for each nucleotide.[12]

Each member received a woolen necktie having an embroidered helix, hence the name "RNA Tie Club".[12]

Members

Member Training RNA Tie Club Designation Officer designation
George Gamow Physicist ALA Synthesizer
Alexander Rich Biochemist ARG Lord Privy Seal of the British Cabinet
Paul Doty Physical Chemist ASP
Robert Ledley Mathematical Biophysicist ASN
Martynas Ycas Biochemist CYS Archivist
Robley Williams Electron Microscopist GLU
Alexander Dounce Biochemist GLN
Richard Feynman Theoretical Physicist GLY
Melvin Calvin Chemist HIS
Norman Simmons Biochemist ILE
Edward Teller Physicist LEU
Erwin Chargaff Biochemist LYS
Nicholas Metropolis Physicist, Mathematician MET
Gunther Stent Physical Chemist PHE
James Watson Biologist PRO Optimist
Harold Gordon Biologist SER
Leslie Orgel Theoretical Chemist THR
Max Delbrück Theoretical Physicist TRP
Francis Crick Physicist TYR Pessimist
Sydney Brenner Biologist VAL

The tie and tiepin

Members of the RNA Tie Club received a black wool-knit tie with a green and yellow RNA helix emblazoned on it. The original design of the tie came from Orgel, with the final pattern re-imagined by Gamow.[12] Gamow's tie pattern was delivered to a Los Angeles haberdasher on Colorado Avenue by Watson, with the shop tailor promising to make the ties for $4 each.[13] Along with each tie, members of the club were to receive a golden tiepin with the three letter abbreviation of their club amino acid designation. Not all members may have received their pin. Gamow, however, wore his pin on several occasions, often causing confusion and questioning of why he was wearing the "wrong initials".[13]

Successes

The RNA Tie Club never had a formal meeting of all its members.[2] Members visited each other to discuss the scientific developments, usually involving cigars and alcohol. This allowed bonding and close friendships to develop among this scientific elite, and it turned out to be a breeding ground for creative ideas. The members mailed letters and preprints of articles to each other suggesting new concepts and ideas.[14]

Number of nucleotides in a codon

Further information: George Gamow § DNA and RNA

Using mathematics, Gamow postulated that a nucleotide code consisting of three letters (triplets) would be enough to define all 20 amino acids.[11] This concept is the basis of "codons", and set an upper and lower limit on their size. Gamow had simply estimated that the number of bases and their complementary pairs in a DNA strand could create 20 cavities for amino acids, meaning that 20 different amino acids could be involved in protein synthesis.[15] He named this DNA–protein interaction the "diamond code."[16] Although Gamow's premise that DNA directly synthesized proteins was proven wrong,[10] the triplet code became the foundation of genetic code.[16]

Codons

Sydney Brenner proposed the concept of the codon, the idea that three non-overlapping nucleotides could code for one amino acid.[17] His proof involved statistics and experimental evidence from amino acid protein sequences.

Adaptor hypothesis

Francis Crick proposed the "adaptor hypothesis" (a name given by Brenner[18]) suggesting that some molecule ferried the amino acids around, and put them in the correct order corresponding to the nucleic acid sequence.[19] The hypothesis contradicted Gamow's direct DNA template hypothesis, positing that DNA could not synthesise proteins directly, but instead requires other molecules, adaptors to convert the DNA sequences to amino acid sequences. He also suggested that there were such 20 separate adaptor molecules.[20][21] This was later confirmed by Robert Holley and the adaptor molecules were named transfer RNAs (tRNAs).[22]

The typed paper distributed to the members of the RNA Tie Club in January 1955 as "On Degenerate Templates and the Adaptor Hypothesis: A Note for the RNA Tie Club" is described as "one of the most important unpublished articles in the history of science",[23][24] and "the most famous unpublished paper in the annals of molecular biology."[24] Watson recalled, "The most famous of these [unpublished] notes, by Francis, in time would totally change the way we thought about protein synthesis.[2]

Personal successes

Six members of the RNA Tie Club became Nobel laureates: Richard Feynman, Melvin Calvin, James Watson, Max Delbruck, Francis Crick and Sydney Brenner. However, the ultimate goal of understanding and deciphering the code linking nucleic acids and amino acids was achieved by Marshall Nirenberg, who was not a member of the RNA Tie Club,[25] and received the Nobel Prize in Physiology or Medicine in 1968 with Holley and Har Gobind Khorana.[26]

References

  1. ^ Strauss, Bernard S (2019-03-01). "Martynas Yčas: The "Archivist" of the RNA Tie Club". Genetics. 211 (3): 789–795. doi:10.1534/genetics.118.301754. ISSN 1943-2631. PMC 6404253. PMID 30846543.
  2. ^ a b c d e f Watson, James D. (2007). Avoid Boring People: Lessons from a Life in Science. Oxford University Press. p. 112. ISBN 978-0-19-280273-6. OCLC 47716375.
  3. ^ Watson JD, Crick FH (1953). "Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid". Nature. 171 (4356): 737–8. Bibcode:1953Natur.171..737W. doi:10.1038/171737a0. PMID 13054692. S2CID 4253007.
  4. ^ Watson, J. D.; Crick, F. H. (1953-05-30). "Genetical implications of the structure of deoxyribonucleic acid". Nature. 171 (4361): 964–967. Bibcode:1953Natur.171..964W. doi:10.1038/171964b0. ISSN 0028-0836. PMID 13063483. S2CID 4256010.
  5. ^ a b Cobb, Matthew (2017). "60 years ago, Francis Crick changed the logic of biology". PLOS Biology. 15 (9): e2003243. doi:10.1371/journal.pbio.2003243. PMC 5602739. PMID 28922352.
  6. ^ Pardee, A. B. (1954). "Nucleic acid precursors and protein synthesis". Proceedings of the National Academy of Sciences of the United States of America. 40 (5): 263–270. Bibcode:1954PNAS...40..263P. doi:10.1073/pnas.40.5.263. PMC 534118. PMID 16589470.
  7. ^ Stegmann, Ulrich E. (2016-09-01). "'Genetic Coding' Reconsidered: An Analysis of Actual Usage". The British Journal for the Philosophy of Science. 67 (3): 707–730. doi:10.1093/bjps/axv007. ISSN 0007-0882. PMC 4990703. PMID 27924115.
  8. ^ Rich, Alexander (2009). "The Era of RNA Awakening: Structural biology of RNA in the early years". Quarterly Reviews of Biophysics. 42 (2): 117–137. doi:10.1017/S0033583509004776. ISSN 0033-5835. PMID 19638248. S2CID 2285884.
  9. ^ Hayes, Brian (1998). "Computing Science: The Invention of the Genetic Code". American Scientist. 86 (1): 8–14. doi:10.1511/1998.17.3338. ISSN 0003-0996. JSTOR 27856930. S2CID 121907709.
  10. ^ a b Segrè, Gino (2000). "The Big Bang and the genetic code". Nature. 404 (6777): 437. doi:10.1038/35006517. PMID 10761891. S2CID 205005362.
  11. ^ a b Gamow, G. (1954). "Possible Relation between Deoxyribonucleic Acid and Protein Structures". Nature. 173 (4398): 318. Bibcode:1954Natur.173..318G. doi:10.1038/173318a0. S2CID 4279494.
  12. ^ a b c d Lily E. Kay (2000.) Who Wrote the Book of Life?: A History of the Genetic Code, Stanford University Press. ISBN 9780804734172.
  13. ^ a b Watson, J. D. (2002). Genes, Girls, and Gamow: After the Double Helix. New York: Random House. ISBN 0-375-41283-2. OCLC 47716375.
  14. ^ Friedberg, Errol C: The Writing Life of James D. Watson, Cold Spring Harbor Laboratory Press, September 2004.
  15. ^ Watanabe, Kimitsuna (2001-05-30). "Genetic Code: Introduction". eLS (1 ed.). John Wiley & Sons, Ltd. pp. 1–10. doi:10.1002/9780470015902.a0000809.pub2. ISBN 978-0-470-01617-6.
  16. ^ a b Hayes, Brian (1998). "Computing Science: The Invention of the Genetic Code". American Scientist. 86 (1): 8–14. doi:10.1511/1998.17.3338. ISSN 0003-0996. JSTOR 27856930. S2CID 121907709.
  17. ^ Brenner, Sydney: On the Impossibility of All Overlapping Triplet Codes, 1956,
    later published in PNAS: PNAS USA. 1957 August 15; 43(8): 687–694.
  18. ^ Crick, Francis (1955). "On Degenerate Templates and the Adaptor Hypothesis: A Note for the RNA Tie Club". National Library of Medicine. Retrieved 2022-07-21.
  19. ^ Crick, Francis, and Brenner, Sydney: Some Footnotes on Protein Synthesis: A Note for the RNA Tie Club. December 1959.
  20. ^ Crick, Francis: From DNA to protein On degenerate templates and the adapter hypothesis: a note for the RNA Tie Club, 1955.
  21. ^ Crick, Francis: What Mad Pursuit 1988, pg 95-96.
  22. ^ Barciszewska, Mirosława Z.; Perrigue, Patrick M.; Barciszewski, Jan (2016). "tRNA--the golden standard in molecular biology". Molecular BioSystems. 12 (1): 12–17. doi:10.1039/c5mb00557d. PMID 26549858.
  23. ^ "Francis Crick - Profiles in Science Search Results". profiles.nlm.nih.gov. Retrieved 2022-07-21.
  24. ^ a b Fry, Michael (2022). "Crick's Adaptor Hypothesis and the Discovery of Transfer RNA: Experiment Surpassing Theoretical Prediction". Philosophy, Theory, and Practice in Biology. 14. doi:10.3998/ptpbio.2628. ISSN 2475-3025. S2CID 249112573.
  25. ^ Everson, Ted: The gene: a historical perspective, pg 90-91.
  26. ^ Nazarali, Adil J. (2011-06-01). "Marshall Nirenberg 1927–2010". Cellular and Molecular Neurobiology. 31 (6): 805–807. doi:10.1007/s10571-011-9709-y. ISSN 1573-6830. PMID 21630009. S2CID 35080749.
Kembali kehalaman sebelumnya