Category: Podcast

Assortative mating is essentially the recognition that theory isn’t always perfect and that, however desperately biologists might want some simplicity in the world, organisms don’t just encounter each other like gas molecules- it’s not a random process. In fact, it can even give evolution a helping hand…

Sources for this episode: 1) Thain, M., and Hickman, M. (2014), The Penguin Dictionary of Biology, 11th edition. London: Penguin Publishing Group. 2) Nishi, A., Alexander, M., Fowler, J. H. and Christakis, N. A. (2020), Assortative mating at loci under recent natural selection in humans. BioSystems 187 (2020) 104040.

Hi everyone, Vince here with a quick update- the podcast now has an accompanying website! From now on, you can head to ‘www.biopedia.co.uk’ to access all our episodes, as well as a blog featuring extra content. Thank you all for sticking with the show and I’m excited to add new content!

The adaptive landscape is an important method for biologists, ecologists, and geneticists to visualise the process of evolution. But what is it, and how does it work? This week, we’re going to discuss what the adaptive landscape actually is, so while there are going to be some sources listed, there’s also a bit of general discussion as well.

Some sources for this episode: 1) Martin, C. H. and Wainwright, P. C. (2013), Multiple fitness peaks on the adaptive landscape drive adaptive radiation in the wild. Science 339: 208- 211. 2) The Wikipedia article for ‘Fitness Landscape’ has quite a good visual guide for rugged landscapes. 3) Script writing was reinforced by my previous education on the topic.

Bonus episode! In the main episode on Sunday, I briefly mentioned NRAMP1, a mutation in which can influence how susceptible someone is to the leprosy bacterium, Mycobacterium leprae. But what exactly is the NRAMP1 protein and why is it important?

Sources for this episode: 1) Cannone-Hergaux, F., Calafat, J., Richer, E., Cellier, M., Grinstein, S., Borregaard, N. and Gros, P. (2002), Expression and subcellular localisation of NRAMP1 in neutrophil granules. Blood 100(1): 268- 275. 2) Forbes, J. R. and Gros, P. (2003), Iron, manganese, and cobalt transport by Nramp1 (Slc11a1) and Nramp2 (Slc11a2) expressed at the plasma membrane. Blood 102(5): 1884- 1892. 3) Rørvig, S., Østergaard, O., Heegaard, N. H. H. and Borregaard, N. (2013), Proteome profiling of human neutrophil granule subsets, secretory vesicles, and cell membrane: correlation with transcriptome profiling of neutrophil precursors. Journal of Leukocyte Biology 94: 711- 721. 4) Hennigar, S. R. and McClung, J. P. (2016), Nutritional Immunity: Starving Pathogens of Trace Minerals. American Journal of Lifestyle Medicine 10(3): 170- 173.

A paper that mentions cell lysis in the context of pathogens surviving phagocytosis: Natural Resistance to Infection with Intracellular Pathogens: The Nramp1 Protein Is Recruited to the Membrane of the Phagosome.

Happy new year! In our inaugural episode of 2021, we’re going to go back to the 1100s and focus on the famous case of the Leper King Baldwin IV, who ruled as king of Jerusalem from 1174 to 1185. What exactly is leprosy, and what causes it? We’ll use the test case of Baldwin as an opening to talking a bit about the bug Mycobacterium leprae and how exactly leprosy works.

Sources for this episode: 1) Guerrero-Peral, A. L. (2009), Neurological manifestations of the leprosy of King Baldwin IV of Jerusalem. Revista de Neurologica 49(8). 2) Turner, J. J., Hektoen International, The remarkable Baldwin IV: leper and king of Jerusalem (online). 3) Fullick A., Locke, J. and Bircher, P. (2015), A Level Biology for OCR A. Oxford: Oxford University Press. 4) Author unknown, Microbiology Society (2014), Mycobacterium leprae, the cause of leprosy.(online) [Accessed 11/12/2020] 5) Abel, L., Sánchez, F. O., Oberti, J., Thuc, N. V., Van Hoa, L., Lap, V. D., Skamene, E., Lagrange, P. H. and Schurr, E. (1998), Susceptibility to Leprosy Is Linked to the Human NRAMP1 Gene. The Journal of Infectious Diseases 177: 133- 145. This paper is from 1998 not 1997- apologies, I read the wrong date on the paper!

Proteins are often mentioned on the show, but what about the building blocks that they consist of? This week, we’re going to tackle amino acids in our second rewind episodes. There are some topics that naturally branch off from this one, such as interactions between amino acids and how DNA encodes for different ones, but I’m going to save these topics for future rewind episodes.

Sources for this episode: 1) Thain, M., and Hickman, M. (2014), The Penguin Dictionary of Biology, 11thedition. London: Penguin Publishing Group. (p.26). 2) Campbell, N. A., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V. and Reece, J. B. (2018), Biology: a global approach, 11th edition (Global Edition), Harlow, Pearson Education Limited: p.973. 3) Compound Interest- A Brief Guide to the Twenty Common Amino Acids (webpage). 4) Fullick A., Locke, J. and Bircher, P. (2015), A Level Biology for OCR A. Oxford: Oxford University Press. 5) Ritchie, R. and Ghent, D. (2015), A Level Chemistry for OCR A. Oxford: Oxford University Press.

Side note: In case this wasn’t clear in the audio, variable groups, R groups and side chains all refer to the same functional group- namely, the variable part of an amino acid.

Building on our discussion of both signalling pathways and G-protein coupled receptors from a few weeks ago, this week we’re going to discuss the Wnt signalling pathway- a pathway which is crucial in aspects of development and can have widespread impacts on the cell. It all sounds rather intimidating, but there’s actually surprisingly few steps involved in this pathway- and we’re only going to be focusing on one part of the signalling network, which makes life a lot less complicated!

Sources for this episode: 1) Alberts, Johnson, Lewis, Raff, Roberts, and Walter (2008), Molecular Biology of the Cell, Fifth Edition, p.948- 950. Abingdon: Garland Science, ‘Taylor and Francis Group LLC’ 2) National Center for Biotechnology Information (2020). PubChem Compound Summary for CID 445638, Palmitoleic acid. Retrieved November 29, 2020 from https://pubchem.ncbi.nlm.nih.gov/compound/Palmitoleic-acid 3) Janda, C. Y., Waghray, D., Levin, A. M., Thomas, C. and Garcia, K. C. (2012), Structural basis of Wnt recognition by Frizzled. Science 337: 59- 63.

In the first of our ‘Rewind’ episodes, we go back to basics and discuss cells- where they came from and the famous cell theory of 1839, which is still present in textbooks today. There are more stories than we can cover which lead up to cell theory, so just see this as an introductory episode until when and if we can come back to these famous names and discoveries.

Sources for this episode: 1) Author unknown, National Geographic, date unknown, Cell Theory (Encyclopaedic entry, online). 2) Silver (1987), Virchow, the Heroic Health Model in Medicine: Health Policy by Accolade. AJPH 77(1): 82- 88 (p.86 for the discussion of Remak).

Please note: at 02:29 I mention that the postulates were ‘released’. I am not sure if this is the right word to use, but I am still looking into this, so watch this space for now.

As discussed in previous episodes, the actin cytoskeleton is vital to allow cells to move. But what about the specifics? In this episode, we’re going to be dissecting the lamellipodium- a meshwork actin structure that some cells use to move.

Sources for this episode: 1) Alberts, Johnson, Lewis, Raff, Roberts, and Walter (2008), Molecular Biology of the Cell, Fifth Edition. Abingdon: Garland Science, ‘Taylor and Francis Group LLC’ 2) ‘Mechanobiology Institute, Singapore’, 2013 (YouTube), Arp2/3 complex mediated actin nucleation (online) [Accessed 23/11/2020] 3) Berro, Michelot, Blanchoin, Kovar and Martiel (2007), Attachment Conditions Control Actin Filament Buckling and the Production of Forces. Biophysical Journal 92(7): 2546- 2558. 4) Kiuchi, Ohashi, Kurita and Mizuno (2007), Cofilin promotes stimulus-induced lamellipodium formation by generating an abundant supply of actin monomers. The Journal of Cell Biology 177(3): 465- 476.

We’re all familiar with the platypus, but it still has surprises up its sleeve. On the podcast today, we get to know its bumper-sized cousin- Obdurodon tharalkooschild.

Sources for this episode: 1) Pian, R., Archer, M. And Hand, S. J. (2013), A new, giant platypus, Obdurodon tharalkooschild, sp. nov. (Monotremata, Ornithorhynchidae), from the Riversleigh, World Heritage Area, Australia. Journal of Vertebrate Paleontology 33(6): 1255- 1259. 2)Dell’Amore, C., National Geographic (2013), Giant Platypus Found, Shakes Up Evolutionary Tree (online) [Accessed 17/11/2020, 11:36 am].