What’s the common thread between protein translation in E. coli and the Loch Ness monster? Seem pretty unrelated, don’t they? Well, not exactly. There’s a pretty roundabout way to get there - one of many.
Statements like “DNA contains instructions for cellular functions”, and “proteins are the building blocks of the body”, or variants of these are some of the one-liners that dotted our childhood. But only when we grew up, did we learn that protein translation is one of the intermediate processes that help produce the proteins necessary for the various bodily functions, from the genetic code contained in cells. tRNAs or transfer RNAs are the molecules responsible for fetching the required amino acids (the components of the proteins, based on the transcribed DNA sequence) during assembly of the various proteins, across all organisms.
Just as incredible as the process of translation seems, there is still scope for error in it. One possible source of mistakes is the ‘wobble effect’. The effect is a consequence of the somewhat loose pairing between the third base of the mRNA codon and the first base in the tRNA anticodon. Bypassing the details, suffice it to say that this leads to a mismatch between the amino acid required per the genetic code and the one
that finally gets placed. Fortunately, mechanisms have also evolved to reduce such errors.
When the nucleoside guanosine gets modified to ‘queuosine’ at the wobble anticodon position on some tRNAs, they are called Q-tRNAs. With an increased abundance of Q-tRNAs, the protein sequence seems better maintained along with improved translation rates – at least in germ-free mice (Tuorto et al., 2018). While queuosine occurs in both eukaryotic and prokaryotic tRNA, eukaryotes only gather it in trace amounts from food and their microbial flora. The synthesis of queuosine happens in prokaryotes like E. coli, and consequently gets used in the translation.
One of the intermediates of the biochemical pathways involved in the synthesis of queuosine from guanosine is the molecule 6-carboxy-5,6,7,8-tetrahydropterin. Sound familiar? Well, how about now, when you know that it’s abbreviated as CPH4? Before you make any conclusions, let me clarify that this molecule has nothing whatsoever to do with the wonder-drug CPH4 that gives the titular character all her fantastic powers in the 2014 film, ‘Lucy’, except for their shared name. CPH4 in the movie supposedly is a compound produced by mothers in the 6th week of their pregnancy, and in large doses, helps Lucy unlock the 90% of her brainpower that apparently lies unused in all humans. This very idea and the plot that follows are purely fictional, as the director himself admits – although he does claim that there is a potent compound of a different name which gets secreted at the 6th week of pregnancy and helps the foetus grow. The existence and identity of this compound may be debatable (Skeptics Stack Exchange, n.d.). Still, its use as portrayed in the movie is undoubtedly inaccurate because the very assertion that only 10% of the human brain is functional (at any given time) is baseless.
While the “10% brain usage” quip is widely toted, it has been conclusively disproved via several different lines of reasoning. Some reasons are that: it makes no evolutionary sense for such large brain sizes to persist if only 10% of it is getting used, and that brain FMRIs have revealed all parts of the brain showing some amount of activity during any given task (Boyd, R., 2008). Yet, this theory has had many proponents and continues to enjoy traction even today. One of the more notable exponents was John W. Campbell, Jr., the well-known American Science-fiction writer. He opined that the unused potential of the brain, when unleashed, could give one psychic powers that could be channelled through the use of electronic devices (or just their blueprints) such as the Hieronymus machine! Even more bizarrely, this machine received a U.S. patent for “detection of emanations from materials and measurement of the volumes thereof” (Hieronymus, T. G., 1949). The emanations here could pertain to many things including what T.G. Hieronymus, the inventor, called “eloptic radiation” – a new form of energy that was supposed to be a combination of electrical and optical energy. Clearly, these are examples of what is called pseudoscience.
So what is pseudoscience? It consists of assertions, practices and branches of study that claim to be scientific but are actually inconsistent with science. That said, it is not very easy to classify something as pseudoscience. Would aberrant results from an experiment that get published be called pseudoscience? No, it certainly doesn’t make sense to be labelled so. But repeated publicizing of the aberrant results by the author despite disagreement by peers should possibly be termed so. Naming the criteria for this classification is a non-trivial problem called the ‘problem of demarcation’ which has a varied history.
Interestingly, all non-science is not pseudoscience. Things that conflict with science are unscientific and need to satisfy additional criteria in order to be pseudoscientific. The likes of Karl Popper, Paul Thagard and many others have tried their hand at devising litmus tests for pseudoscience. Absence of falsifiable assertions, failure of the theory to progress, an apathetic attitude of scientists towards applying or evaluating the theory, cherry-picking of favourable examples, experiments that evade repetition, neglect of contradictory information and belief in authority are just a few of them (Hanson, S.O., 2017). Yet, there is no one-size-fits-all template to identify pseudoscience, and the boundaries could be vague.
The most effective tool by far in recognizing pseudoscience is ‘scientific scepticism’ – an impartial attitude towards anything, until investigation via multiple lines reinforces the claim or hypothesis, failing which doubts will continue to be harboured. In statistical language, the null hypothesis (or the hypothesis assumed to be true before testing) when examining any claim is to consider it false. In the presence of conclusive evidence to the contrary after testing, the null hypothesis is rejected, and the alternative hypothesis (that the claim is true) is adopted (Shermer, M., 2009). Scientific scepticism differs from the other forms of philosophical scepticism in that the latter puts forth that we can never gain knowledge or make conclusions about the nature of the world and questions even scientifically accepted statements.
Given all this, scientific scepticism does seem like a nice middle-ground that may help us move closer to the abject reality and tune out the other discordant narratives that we are spectators of – such as chiropractic practices and the Loch Ness monster.
REFERENCES:
(Apart from the liberal use of Wikipedia)
Boyd, R., (2008, February 07). Do People Only Use 10 Percent of Their Brains? Scientific American. Retrieved July 29, 2020, from https://www.scientificamerican.com/article/do-people-only-use-10-percent-of-their-brains/
Skeptics Stack Exchange. (n.d.). Is CPH4 from science fiction movie ‘Lucy’ real? Retrieved July 29, 2020, from https://skeptics.stackexchange.com/questions/22785/is-cph4-from-science-fiction-movie-lucy-real
Hansson , S. O. (2017). Science and Pseudo-Science. The Stanford Encyclopedia of Philosophy (Summer 2017 Edition), Edward N. Zalta (ed.). https://plato.stanford.edu/archives/sum2017/entries/pseudo-science/
Hieronymus, T. G. (1949). Detection of emanations from materials and measurement of the volumes thereof. (United States US2482773A). USPTO. https://patents.google.com/patent/US2482773
Shermer, M., (2009, July 01). What Skepticism Reveals About Science. Scientific American. Retrieved July 29, 2020, from https://www.scientificamerican.com/article/what-skepticism-reveals/
Tuorto, F., Legrand, C., Cirzi, C., Federico, G., Liebers, R., Muller, M., Ehrenhofer-Murray, A., Dittmar, G., Grone, H., Lyko, F. (2018) Queuosine‐modified tRNAs confer nutritional control of protein translation EMBO J 37 e99777 https://doi.org/10.15252/embj.201899777
IMAGE REFERENCES:
Cover image. Retrieved on July 29, 2020, from http://homepages.wmich.edu/~korista/sci-pseudo-rel.html
Diagram showing the translation of mRNA and the synthesis of proteins by a ribosome. Retrieved on July 29, 2020, from https://en.wikipedia.org/wiki/Translation_(biology)
Chemical Structure Depiction. Retrieved on July 29, 2020, from https://pubchem.ncbi.nlm.nih.gov/compound/Queuosine#section=Structures
Theatrical release poster. Retrieved on July 29, 2020, from https://en.wikipedia.org/wiki/Lucy_(2014_film)
Fig. 1. Hieronymus, T. G. (1949). Detection of emanations from materials and measurement of the volumes thereof. (United States US2482773A). USPTO. https://patents.google.com/patent/US2482773
A hoax photo of the Loch Ness monster from 1934. Retrieved on July 29, 2020, from https://www.bbc.co.uk/newsround/48499253
A note about the author:
Sumedha is a BS-MS student at IISER-Kolkata majoring in Earth Sciences. She loves reading books across genres and is curious about languages, life, math and much more.
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