Department of Biology
York Biology Open Lectures
These lectures are open to all members of the University and the public.
Admission is free and no booking is required. Each of the speakers is both a distinguished scientist and a good communicator. The lectures aim to capture the imagination of everyone interested in biology.
Body clocks: your inner daily life and its relationship to health
23 January 2013, 1.15 pm
Speaker: Dr Michael Hastings, FRS, MRC, Laboratory of Molecular Biology
Life inhabits a 24-hour world. To make the most of the opportunities presented by day and by night, and to avoid their attendant dangers, living organisms from bacteria to people have daily rhythms of metabolism and behaviour that “tune” them to the world. These rhythms are driven by biological clocks, which are called circadian (latin: circa- approximately, diem-one day) because they run, self-propelled, on an approximately 24 h cycle. The most obvious of our circadian rhythms is sleep, but circadian clocks also control all aspects of our physiology. The recent identification of genes encoding the clockwork has revolutionised our understanding by showing that the core mechanism is a feedback loop in which these genes are alternately switched on and off by the “clock” proteins they encode.
Remarkably, most cells in our body have their own clocks, ultimately controlled by the brain’s central pacemaker in a region called the suprachiasmatic nucleus. The recognition that our brains and bodies are 24 hour machines has great relevance to health and disease. For example, at a molecular level the circadian clockwork enmeshes with a second biological timer, the cell cycle. Consequently new avenues are opening for understanding the temporal regulation of cell division and how it goes wrong in cancer. Equally, molecular and cellular advances highlight new therapeutic approaches, for example by exploiting circadian changes in the body to maximise the efficacy of medicines. Finally, circadian disruption is a feature of modern life- resulting from “24/7” culture and shift work, or increasing longevity and associated dementia. Understanding the body’s clockwork is a necessary step towards managing these growing problems with their attendant personal, social and economic costs.
Location: Physics, P/X001
From meerkats to antimicrobials - a case study in unexpected applications from pure science
5 March 2013, 6.30 pm
Speaker: Dr Ashleigh Griffin, The University of Oxford
Science is usually consumed in bite-sized chunks in the shape of individual publications, and research horizons are often set by the length of the next research grant. This can obscure the fascinating twists and turns, often unexpected, that characterise the most exciting and innovative research. In my talk, I want to take the opportunity to present a more longitudinal view of how pure research can lead to applications using my own research career as an example: fifteen years ago I was studying meerkats for my PhD in the Kalahari desert and that work has led directly to current projects developing novel strategies for combating the spread of antibiotic resistance in bacterial infections. In the current economic climate, it is more important than ever that politicians have public support for funding pure science and resisting pressure to further judge research in narrow terms of immediate economic importance.
Location: Physics, P/X001
RNA splicing at the centre of gene expression
Wednesday 13 March 2013, 1:15 pm
Speaker: Professor Jean Beggs, FRS, CBE, Wellcome Trust Centre for Cell Biology, University of Edinburgh
In most eukaryotic genes the coding information in the DNA sequence is interrupted by non-coding regions called “introns”. Transcription produces an RNA copy of the gene, which includes the introns. The RNA has to be cut and the coding sequences spliced together to remove the introns and produce a continuous “message” with the correct information to produce a protein. Mistakes in RNA splicing cause serious problems for the cell, as defective proteins are produced, and this sometimes happens as a consequence of genetic defects or disease. Also, as coding sequences can be spliced together in different ways, giving rise to different proteins, this is an important mechanism for increasing the coding capacity of a genome. RNA splicing is herefore a critical process at the centre of gene expression, and there is evidence for proofreading activities that check the fidelity of splicing.
It is now apparent that RNA splicing does not take place independently of other cellular processes. For example, we have obtained evidence that splicing can affect the progress of transcription, and it seems that transcription and splicing are functionally coupled. We propose the existence of transcriptional checkpoints that respond to the proofreading activities that check the fidelity of splicing. We use budding yeast as a model organism as many powerful experimental techniques are available and, as the splicing process is highly conserved, it can provide important insights into splicing in humans.
Location: Biology, B/B002
Making more of medicinal plants: cures for all ills
Wednesday 17 October 2012, 1.15pm
Speaker: Professor Ian Graham, CNAP, University of York
Plants have evolved to produce a vast array of complex chemical structures to fight off attacks from herbivores and pathogens and to protect themselves from often hostile environments. These chemical structures or natural products also provide plants with medicinal properties that human civilisation has relied on for millennia. We now know the identity of the chemicals responsible for a number of these medicinal properties. Many of these are difficult to synthesise chemically and we still rely on plants for their production. This lecture will focus on two such molecules. The first is a complex terpene molecule called artemisinin, which kills the malaria parasite and is the most effective drug in the fight against malaria. We have been developing new varieties of the plant Artemisia annua, that produces artemisinin and we will explore how and where the chemical is made and how you can develop plants to make more of it. The second example is a complex alkaloid called noscapine, which has been used for decades as an anti-tussive in cough medicine and more recently has been found to have anti-cancer properties. Noscapine is produced in opium poppy, which is also still used as the major source of the pain relief drugs morphine and codeine. We have recently discovered that ten of the genes responsible for making noscapine in poppy are present in a cluster in the genome. This has allowed us to very quickly work out how noscapine is made and breed new varieties of poppy that make more of it. We can measure over 200 different alkaloids in opium poppy and a similar number of terpenoids in Artemisia annua. These are often at very low abundance, but once we work out ways to make more of them it is likely that they will provide a rich source of cures for the ills of present and future human civilisation.
This York Biology Open Lecture has been specifically arranged as part of the first ever Biology Week, organised by the Society of Biology.
Location: Physics, P/X001
Embryos, stem cells and regenerative medicine
Wednesday 31 October 2012, 1.15pm
Speaker: Professor Cheryll Tickle, FRS, University of Bath
The long term goal of regenerative medicine is to replace, repair and regenerate damaged or defective tissues and organs. In one main strategy, the aim is to effect repairs by transplanting cells or tissue-like structures built from cells; in another, the aim is to stimulate cells around the damaged tissue to regenerate. Both strategies can be combined with inert scaffolds to support the transplanted or the regenerating cells. Most of the fundamental biological knowledge on which these strategies are based has come from studying the development of embryos of model organisms. Early embryos including human embryos contain stem cells that give rise to all the different tissues of the body. Many of the molecules involved in embryonic development –mostly proteins encoded by genes- have also been discovered. Luckily, it turns out that the same families of molecules control the development of a fly and of a human being. Thus these molecules can be used to control behaviour of human stem cells and have the potential to be used clinically to stimulate repair and regeneration. The embryo can also give lessons on how to make a complex structure such as a limb and the challenge is to find ways of applying these lessons to regenerative medicine.
Location: Physics, P/X001
Sequencing the unseen animal: using modern genomics to reveal biodiversity
Wednesday 7 November 2012, 1.15pm
Speaker: Professor Mark Blaxter, GenePool, University of Edinburgh
The vast majority of life on earth is tiny, visible only through the microscope. Despite their size, these organisms actually deliver most of the activity that drives the biosphere: they are present in vast numbers. While most members of this tiny biosphere are prokaryotes (bacteria and archaea) and protozoa, this group also includes animals. Unsurprisingly, these unseen animals are not well understood, and there are likely to be millions to tens of millions of undescribed species. They live mainly in sediments (soils and muds). Excitingly, the global lack of knowledge of these animals means that there are likely to be species new to science in every habitat, including suburban soils and local estuary muds.
The problem of how to count and categorise these animals is not a new one, but new DNA-based technologies are transforming understanding. By isolating and counting specific small fragments of each animal's DNA genome, we can both identify what is there and count their abundances, revealing the hidden biosphere in details previously unimagined. The new DNA technologies also allow us to explore in great detail exactly what it is these animals do. By analysing the whole genome (rather than just a marker DNA fragment) we can build a model of the biology of a species, and thus its likely roles in the ecosystems it is part of.
Location: Physics, P/X001
Please Note: This is an Evening Lecture!
Technology and magic
Thursday 22 November 2012, 6.30pm
Speaker: Professor Jack Cohen, University of Warwick
Arthur C Clarke put it well: “Any sufficiently advanced technical process is indistinguishable from magic!” That's fine if you're a chemist or an engineer or an astronomer – but it's no good if you're a biologist! Biology starts off incomprehensible and gets worse: even the simplest of cells seems so complex that we've got to call it ‘magic’, from the start. Every organism, every activity, is magical… But there’s a lot of quite ordinary, comprehensible biological technology that it seems the ‘magic’ rests on. Well, it’s not quite like that. I give several examples where the technology is easy, but the argument is magical! From the Belousov-Zhabotinski reaction making order from chaos (demonstrated with real chemistry!) to needing to distil water six times for IVF, to eels journeying from – and perhaps to – the Sargasso Sea, to stick insect eggs resembling seeds - there are innumerable examples. One which is close to my heart concerns work I did in the 1970’s and ‘80’s on sperm selection, showing that only a few – different - sperms normally ‘make it’! The technology was admired, but the conclusion – the ‘magic’ – is still not believed by most andrologists! There’s an interesting test just waiting to be done!
Location: D/N/028 Lecture room (Derwent College, Heslington West)