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The lab is looking to recruit new postdocs and grad students. Our lab investigates how growth is controlled during animal development. We use a combination of molecular and genetic approaches to investigate the cell-cell signalling pathways and the genetic mechanisms that govern the control of cell, tissue and body growth in Drosophila. Our main focus to-date has been the conserved insulin and TOR kinase pathways, and understanding how they regulate cellular and animal metabolism to drive growth. Further information on our research can be found here. Recent publications can be found here.
POSTDOCS: applicants with a Ph.D. and strong background in developmental biology, genetics, or molecular biology are encouraged to apply. Interested individuals should send a CV and a short statement of research interests to grewalss@ucalgary.
GRAD STUDENTS: applicants with a strong undergraduate degree in any area related to the biological sciences are encouraged to apply. Interested individuals should send a CV and a short statement of research interests to grewalss@ucalgary.
Scientific research is portrayed as an objective pursuit, but it is always influenced by an array of subjective emotions – joy, frustration, rejection, validation, egotism, confidence, worry, friendship, competition, intuition, luck, success, failure. For better or worse, it is these emotions that often determine how discoveries are made and how science is communicated.
I enjoy reading books that delve into the stories behind research discoveries and that reveal the passion, politics and personalities that drive scientific research. I previously compiled some lists of books that I recommend (you can find the lists here and here). Here is a new list of more recent books I’ve read. I hope you enjoy these. Feel free to suggest others – I’m always looking for a good read.
An Essay of Science and Narcissism: How do high-ego personalities drive research in life sciences by Bruno Lemaitre. In this very enjoyable book, Bruno Lemaitre (a Drosophila researcher) gives us his view on how narcissism and ego influence the way modern science (primarily in the biological sciences) is conducted, judged and rewarded. I highly recommend this book – read it and in Bruno’s descriptions, you’ll recognize many prominent researchers in your field. Also keep this book in mind if you read any of the other books on this or my previous lists.
Natural Obsessions by Natalie Angier. During the early ’80s, Natalie Angier spent about a year in the labs of two prominent cancer researchers, Robert Weinberg and Michael Wigler, at a time when both labs were making major discoveries into oncogene function. This book is her account of that time. It’s an amazing book that shows the good (amazing science, great scientists), the bad (competitiveness, shitty mentoring) and ugly (ego, narcissism, sexism) of life in a research lab. Have things changed since the 80s? I’m not so sure, but we definitely need more books like this. Highly recommended!!
A Feeling for the Organism by Evelyn Fox Keller. A detailed account of the life and career of Barbara McClintock. Evelyn Fox Keller does a great job in describing the struggles McClintock faced getting research positions and in discussing why it took so long for her discoveries about transposable elements to be accepted. Hint: sexism.
Elizabeth Blackburn and the Story of Telomeres: Deciphering the Ends of DNA by Catherine Brady. A very nice account of the life and career of Elizabeth Blackburn (written before she was awarded the Nobel prize). It does a great job describing the struggles she faced against gender discrimination, and also the political battles she faced regarding stem cell research when she was on the President’s Council on Bioethics during the Bush years.
Dorothy Hodgkin: A Life by Georgina Ferry. A great account of the life of one of the great scientists of the last century and the only British female scientist to receive the Nobel Prize.
Life’s Great Secret: The Race to Crack the Genetic Code by Matthew Cobb. Like the superb ‘The Eighth Day of Creation” by Horace Freeland Judson, this excellent book by Cobb describes the period spanning the work that led to the discovery of the structure of DNA to the early days of molecular biology, when the processes of gene transcription and translation were just being described and understood. This book also goes a little further than Judson’s, and describes the implications of this ‘golden age of molecular biology’ for science and society now.
In Search of Memory: The emergence of a new science of mind by Eric Kandel. An enjoyable memoir from Kandel describing his early life and his research career – I refer you to Lemaitre’s book above. This book also includes a bizarre description of an event in young Kandel’s life – what a perv.
p53: The Gene that Cracked the Cancer Code by Sue Armstrong. A lovely, clear description of the discovery and early research on p53. It does a great job describing the early work that tried to decipher whether p53 was actually an oncogene or tumor suppressor – a great account of how knowledge we take for granted now was not always so clear cut. A great book for grad students.
The Man in the Monkeynut Coat: William Astbury and the forgotten road to the double-helix by Kersten Hall. A very nice book on the life of William Astbury, an important structural biologists, whose role in the research leading up to the discovery of the double helix structure of DNA is often forgotten.
Life’s Blueprint: The science and art of embryo creation. by Benny Shilo. A lovely, layman’s account of the process of embryogenesis by Benny Shilo (another Drosophila researcher). The book juxtaposes images of developing embryos and organisms with Benny’s own beautiful photography such that the photos become visual metaphor for the developmental process.
In our last journal club we discussed two very nice papers on sexual dimorphism in Drosophila intestines that controls growth, regeneration and lifespan:
Sex difference in pathology of the ageing gut mediates the greater response of female lifespan to dietary restriction. Regan JC, Khericha M, Dobson AJ, Bolukbasi E, Rattanavirotkul N, Partridge L. Elife. 2016 Feb 16;5. pii: e10956.
In the first paper, Bruno Hudry (from the lab of Irene Miguel Aliaga) showed that female intestines showed both a marked increase in cell proliferation/regeneration in response to damage and in increase propensity to develop tumors. Both these effects were dependent on the sexual identity of the intestinal stem cells, which is controlled by Transformer expression.
The second paper from Jenny Regan described male:female differences in both intestinal pathology in aged guts and response to infection. Interestingly, this paper indicates that these differences are regulated by the sexual identity of the differentiated epithelial cells in the gut, although the differences do involve altered stem cell proliferation.
We liked both papers a lot. Its a topic that we’ve become interested in – our former postdoc, Liz Rideout, recently published a paper on sex differences in insulin signaling and growth in Drosophila, and she’s continuing this work in her own lab at UBC.
In a recent lab journal club we discussed a very nice paper from Takashi Koyama and Christen Mirth:
Nutrients promote body growth in Drosophila by stimulating insulin signaling. One main way that this happens involves endocrine signaling between the fat body and the brain – in protein rich diets, amino acid import into fat body cells activates TOR and leads to release of a secreted factor(s) that acts on the brain to stimulate expression and release of insulin-like peptides (ILPs) from neurosecretory cells. However, the nature of the these AA-sensitive fat body factors has remained elusive. In this paper, the authors identify the Growth Blocking Peptides 1 and 2 (GBP1 and 2) as strong candidates. They show that expression of GBP1 and 2 is regulated by AA/TOR signaling and that both GBP1 and 2 are secreted from the fat body and can act directly on the brain to promote ILP release.
We liked this paper a lot. In particular we appreciated the rigorous and comprehensive approach the authors used to establish that both GBP1 and 2 are bona fide fat-body derived factors that respond to TOR signaling and that act directly on the brain to promote insulin release.
Dietary restriction of amino acids and inhibition of TOR (by Rapamycin) are two robust ways to extend lifespan in flies. Here the authors do some very nice tissue mRNA expression analyses to examine how these two experimental manipulations may affect gene expression. Their data reveal some interesting tissue specific effects in transcription and also point to a role for GATA transcription factors in lifespan-associated transcriptional changes.
We liked this paper – it will open up lots of new work on GATA factors and nutrient/TOR signaling. And we were especially happy to see it on bioRXiv for all to view. Some thoughts we had (mostly for future work): Does TOR signaling regulate the GATA transcription factors? Do these GATA factors regulate lifespan? Might they also be important for nutrient/TOR control of transcription and growth in larvae or do nutrients/TOR regulate two different transcriptional programs in larvae (growth) vs adult (fecundity and lifespan)?
In this paper Okamoto and Nishimra describe how dILP5 mRNA expression is regulated by dietary nutrients (protein). This regulation relies on a relay mechanism involving nutrient-responsive glia, which locally secrete dILP6 to activate cholinergic neurons, which then secrete Jeb that activated the Alk receptor on the surface of IPCs, which then induce dILP5 expression in response to PI3K/Akt activation.
We liked this paper. We were interested in some of the parallels between how IPCs responded to nutrients to control dILP5 and how neuroblasts control their division in response to nutrients (in papers we have discussed in previous lab journal clubs). In both cases, an initial step is local dILP6 secretion from surface glia, however, in the case of neuroblast division, these glia respond to a fat-derived signal release in response to TOR activation (Chell, 2010; Sousa-Nunes, 2011). In this paper, activation of TOR in the fat body appears to be unnecessary. Instead the surface glia respond directly to amino acids and insulins. Similarly the Jeb-ALK pathway is also involved in controlling IPCs in neuroblasts. In this paper, ALK activation of IPCs is necessary to promote dILP5 expression in nutrient-rich conditions. In contrast ALK activation of neuroblasts is required to maintain their proliferation in late larval starvation (brain sparing – Cheng, 2011)