Chromatin, Human Disease Models, and *Friendly* Yeast Debates

Friday was full, diverse, and wonderful! I headed down just before 7am to avoid the breakfast traffic jam, and met the most wonderful postdoc student originally from China named Lifang, now doing his postdoc work in the states. His research is in ciliate genetics, and prior to his postdoc position, he taught undergrads in China. So for the duration of breakfast, I got a free tutoring session on all things ciliate genetics. Score! He started from the beginning, describing the macro- and micronuclei, and went into more complex aspects as I ate my oatmeal and he munched on a blueberry muffin. After his explanations, I understood the ciliate talks that I attended on Thursday much better, but definitely could have used another hour to hear about his own research! 

After this lovely breakfast/learning session, I headed to the glorious Palms Ballroom for the Chromatin & Epigenetics session from the Drosophila community. The first talk was given by Sarah Elgin from Washington University. She discussed her work into the role of repetitious elements driving gene silencing. This was probably one of the most complicated talks I attended all conference long. I had to look up a few things just to understand the abstract! One of the most memorable parts of her talk was the discovery that the extent of a particular form of gene silencing depends on temperature. At lower temperatures, a loss of silencing was observed. This was confusing for Elgin and her colleague in a different lab; while Elgin observed the flies at 18 degrees Celsius, her colleague observed them at 25 degrees Celsius, and the two saw different phenotypes! This initially confusing difference turned out to be a great discovery. 

Another great talk in this session was by Emily Brown from the University of California, Berkely. She studied the lifespan of Drosophila with different genotypes (XX, XXY, XY, XO, and XYY) to determine the role of the Y chromosome in sex-specific ageing. Male flies with genotype XXY had the shortest lifespan, while female flies with genotype XO had the longest lifespan. Thus, a shorter lifespan was correlated with the presence of a Y-chromosome. Brown described how the Y-chromosome acts as a "heterochromatin sink" by acquiring heterochromatic factors from other regions of the genome. 

Here I am in front of the stunning pool. While some were soaking up sunshine, I was looking forward to soaking up all things to do with models of human disease! Right after the Chromatin & Epigenetics session, I made my way to the nearby Crystal Ballroom to attend my first session from the Mouse community. Throughout the seven talks of this session, it quickly became one of my favourite sessions of the whole conference. Michelle Southard-Smith from Vanderbilt University Medical Center gave a fascinating talk on a mouse model of neurocristopathies (pathologies involving cells that are derived from embryonic neural crest cells). In order to do this, Southard-Smith made a Sox10-COIN mutant. She showed videos of the mice so we could easily see just how affected their motor control was. These Sox10-COIN mutants can be used as a model to study diseases such as PCWH (or if you'd like to use the exceptionally long name: Peripheral Demyelinating Neuropathy, Central Dysmyelinating Leukodystrophy, Waardenburg Syndrome, and Hirschsprung Disease).

Suzanne Hartford gave a really interesting talk on the interaction between BRCA2 and PALB2 at the replication fork. The loss of PALB2 leads to an unprotected replication fork and a decrease in genome stability. Additionally, Hartford and her team at the National Cancer Institute in Maryland made the very first mouse model of BRCA2 with a point mutation that affects function! This is yet another example of the mind-boggling work in genetics being done in our lifetime - go Suzanne Hartford, go!

The final speaker, William Barrington, had an exceptionally clear talk on differing responses to a variation of diets between mice of different genetic backgrounds. Wow, was this talk eye-opening and very applicable. With his study, Barrington clearly showed that strains of mice with differing genetic backgrounds had highly individualized responses to four common human diets: American (greasy burgers and french fries), Mediterranean (lots of vegetables and olive oil), ketogenic (very high fat, moderate protein and little carbohydrate) and mouse chow as a control. The four strains of mice had very different levels of adipose, glucose responses... The list goes on! Barrington argued that based on these findings, genetic background should be a major factor when choosing ones' diet. Although his talk was amazing, he didn't discuss how, as humans, we can take our genetic background into account to eat the best way for our particular genotype. Nonetheless, this is ground breaking work and I am sure he will come out with some more amazing studies relating genetics and nutrition. 

During today's poster presentations I made my way through the endless knowledge and discovery and ended up in the Yeast Genetics section, where I spent a good hour at my new friend Alex's poster. I was planning on just a few minutes, but then a postdoc who was studying the same compound (fluconazole) as Alex came by and a healthy discussion ensued. Through this conversation I learned that Hsp90 has previosuly been shown to play a key role in facilitating resistance to fluconazole. Interestingly, however, when the postdoc added an Hsp90 inhibitor (that he made himself!) and another drug at any concentration in combination to fluconazole, the yeast cells lived. The cells had gained resistance to fluconazole, but the mechanism could not have involved Hsp90, since many experiments validated the specificity of the Hsp90 inhibitor! The two bounced ideas off like a game of intellectual ping-pong, and I asked questions throughout, feeling a bit like the moderator as these two yeast researchers questioned, challenged, and advised one another. 

During my time slot at my poster, I had a few different individuals and groups stop by and had some wonderful conversations. Over the course of about an hour, two graduate students from South Korea, two postdocs and one undergrad from Italy, and two PhD students from Memorial University in Newfoundland stopped by! 

After poster presentations I grabbed some lunch and made my way quickly to the Drosophila Models of Human Disease I. I thought it would be a great way to complement the morning session of disease models in mice. As I walked through the first floor to the session, I couldn't resist capturing the beauty of the day (above). This session included talks on insight into Alzheimer's disease, identification of proteins involved in stretching of squamous cells, and mutations in mtDNA. Overall, a session packed with a LOT of details and discovery. 

I ended my day off with the Women in Genetics Panel and Networking event. I had selected this event prior to the conference, and was excited to learn from top female scientists. Seated at my table was a diverse group of researchers, ranging from another undergrad, to a professor, and everything in between. Together, we represented British Columbia, Pennsylvania, Melbourne, and Ontario, just to name the ones I can remember! The two speakers were not only top scientists in their fields, but were also incredibly funny as they shared their journey as females studying science. What stood out to me the most in their presentations was the emphasis on putting yourself out there. They emphasized how science not only relies on what happens in the lab, but on the ability to communicate well and confidently. These two women certainly epitomized this. 

After another excellent day at TAGC 2016, the view from my room was yet again a beautiful sight to behold. This was my last night in Orlando, so I soaked up the peaceful view and looked forward to an exciting workshop happening the following morning!

- Vivienne