Piggyback Microbe and Cancer! Interview with Niranjan Nagarajan on role of microbiome in bile duct cancer.

Cancer is a very complex disease, with various genetic and environmental factors playing a role in its development and growth. Mutations within the cell and signaling among cells is well known to play vital roles. But could there be other players involved in the process. Of note, something which surrounds us at all times: our microbiome?

Our body is composed of as many microbiome as our own cells. A lot of it comes from the food we eat and the water we drink. Along with our meals, food related parasites might bring their own microbiome into our body, and these could in turn home into organs and modify the tissue microenviroment. This is what Niranjan and colleagues see for bile duct cancer - in which liver fluke parasite arriving from consumption of raw fish finds a home in the bile duct and increases the chance of developing cancer. Their work emphasizes an appreciation into the role of microbiota in cancer development. To know more, please listen to Niranjan.  



To learn more, please refer to:
Tissue Microbiome Profiling Identifies an Enrichment of Specific Enteric Bacteria in Opisthorchis viverrini Associated Cholangiocarcinoma
Chng et al., eBioMedicine, June 2016Volume 8, Pages 195–202.

A Mito coup d'cellule! Interview with Hansong Ma on selfish drive in mitochondria!!!

Mitochondria are the power generators of the cell. Each cell has thousands of them, and each has its own genome. The DNA it possesses is needed for survival, and it has to be replicated to generate new ones. This means that mitochondria that can replicate better can out-compete others with replicative disadvantage and, in extreme cases, take over the entire cellular compartment. Since, the cell is blind to such competition, 'bad' or non-functional mitochondria can take over, to their own benefit and to the cell's detriment; thereby leading to 'selfish behavior'. 

This is of particular importance to current human health. UK's decision to allow three-parent baby is a monumental step in curing a set of congenital diseases. In this the defective mitochondria is replaced with that from a healthy donor. But even if a few defective ones remain behind (from among thousands), this also creates a competition among the two populations. And if the selfish drive of the defective one is strong enough, it might again take over the cell, thereby increasing the chance of pathogenesis. A good donor should not only be healthy, but also strong in its selfish drive. To understand how such competition is accomplished, please listen to the interview with Hansong Ma.

For more information, please refer to:

Selfish drive can trump function when animal mitochondrial genomes compete.

Ma and O'Farrell. Nature Genetics 48, 798–802 (2016).

Eat me not! Interview with Anu Chaudhary on cell surface marker regulating autophagy in humans!

Cells are constantly talking with each other, mostly with the help of cell surface receptors and ligands. This includes information on the amount of 'self-digestion' to perform. Higher self-digestion, or autophagy, leads to faster protein turnover and has been implicated in many age-related diseases, esp. those with an autoimmune component. Could we understand the mechanism controlling levels of autophagy and modulate it to affect disease outcomes?

Anu Chaudhary and her colleagues display an elegant way to screen human genetic variation underlying any observable phenomena. By focusing on response to rapamycin, a drug that induces autophagy, they were able to isolate variations that enhance cellular self-digestion. They use this to characterize cell surface receptors that can vary autophagy levels, and use this knowledge to develop means that could deter auto-antibody production. To learn more about the exciting and relevant finding, please listen to Anu.


For further information, please refer:
Human Diversity in a Cell Surface Receptor that Inhibits Autophagy.
Chaudhary et al., Current Biology, 2016.

Music to the heart! Interview with Troy Shirangi on development of neural circuitry for fly courtship behavior!!

You all must have seen a peacock dance. It's majestic, isn't it! The vibrant colors all moving in big waves, but for what?? The male peacock performs the majestic gesture to lure the female into mating. This is true for many species where the male makes ostentatious displays to entice the female. But how does the male develop the displays that the females respond to? Are there special neural circuitry controlling this behavior?? And if so, which genes are responsible for making them???


Troy and his colleagues dissect such machinery for the fruitfly, Drosophila melanogaster. They find the neurons and master transcription factor autonomously controlling the courtship behavior. They are able to specially pin-point the neuro-muscular apparatus underlying male singing. The study lays the platform for understanding sex-specific behaviors and the evolutionary forces underlying mate choice. To understand about the exciting work, please listen to the interview with Troy.


For further information, please refer the following study:
Doublesex Regulates the Connectivity of a Neural Circuit Controlling Drosophila Male Courtship Song
Shirangi et al., Developmental Cell, 20 June 2016.
   

Is to perceive to suffer? Interview with Anjali Krishnan on empathetic pain perception!

Imagine falling on the road and hurting yourself. Now imagine watching the same event happen to someone else. Would you react similarly to both these situations? Would your brain respond alike to your own pain vs. to other's pain. Aristotle once said, 'To perceive is to suffer'. According to him, your reaction would match. But is that true?!

Anjali Krishnan and her colleagues at University of Colorado Boulder set out to find answer to this question of similarities and differences in perceiving self and empathetic pain. Surprisingly, and excitingly, they found that our brain looks at these kinds of pain differently. Empathy for other people's pain involves the process of mentalization: imagining other's situation and condition. To know more about the interesting observation, please listen to interview with Anjali.



To know more, please read here:
Somatic and vicarious pain are represented by dissociable multivariate brain patterns.
Krishnan et al., eLife 2016;5:e15166.

Exercising the old away! -- Interview with Marissa Schafer about exercise decreasing senescent adipocytes!!

We all know the many benefits of exercise, and the evils of fast-food diet. Exercise makes us feel healthy, younger and more vital; while excess of double cheeseburgers gives the lethargic look with tired body. But how exactly does exercise lead to such benefits; and high fat diet lead to such deterioration?

Marissa Schafer and her colleagues at Mayo Clinic asked this simple, yet complex question. What they saw was that high-fat diet was increasing the proportion of senescent fat cells -- cells that are incapable of growing or diving. They saw that such cells were attracting immune system components, that could lead to adverse effects. Exercise on the other hand decreased the presence of such cells, excitingly even in the case of high-fat diet. So, if you have a hamburger, be sure to couple it with a 5k. To know more the exciting study, please listen to the interview with Marissa:


Please refer the following for more information:
Exercise Prevents Diet-induced Cellular Senescence in Adipose Tissue.
Schafer et al., Diabetes 2016.  

One ratio to rule them all! Interview with Leigh Harris about a unified principle regulating bacterial cell size!

We live in a 3D world, in which every object occupies space. Same is true for all cells. The size of biological objects is a ubiquitous property, about which very less is known. How do cells 'measure' their size and how do they regulate it in response to changing environment? These unanswered questions have far-reaching implications on every aspect of biology.

Leigh Harris and her colleagues set out to discover the principles regulating cell size in a simple model, bacteria. She used live imaging and quantitative analysis to accurate measure bacterial cell volume and surface area: two parameters implicated in size control. Excitingly, she was able to come up with a simple ratio: the rate of surface area to volume change, which defines the steady state size and shape of the cell. This presents a novel unified model for regulating bacterial size. Lets call Leigh to understand more about this principle!



To know about the story, please read:
Relative Rates of Surface and Volume Synthesis Set Bacterial Cell Size
Leigh and Theriot, Cell, 2 June 2016.