Food for Eye! Interview with Tiago Santos-Ferreira on cell-support paradigm for retinal transplantation!

Cell-transplantation based therapy is increasingly becoming relevant these days, esp. with a bloom in techniques for stem cell and organoid production. The transplanted cells could greatly benefit treatment of degenerative diseases. But how do the transplants help the diseased organ. The obvious thinking is that they help by providing a fresh supply of healthy cells. But is that always the case?

Tiago and colleagues asked what happens to retinal cells transplanted into a damaged eye. And surprisingly found that the transplanted cells did not integrate into the organ, but rather provided cytoplasmic material to the pre-exisiting host cells. Cytoplasmic material present within the transplanted cells was being taken up by the host cells. This was a clear indication of a new way by which transplants could help the damaged tissue, which could be used to potentially transfer much more cargo in future. To know more, please listen to Tiago.  


For further information, please refer to:
Retinal transplantation of photoreceptors results in donor–host cytoplasmic exchange.
Santos-Ferreira et al., Nature Communications, 2016

Packaging without packets! Interview with Shamba Saha on membrane-less organization within cells!!

How do you organize your stuff at home. In boxes, I suppose. Tucked into boxes, all the stuff is nicely arranged. This is not special to human behavior, as even biological cells use the same principle of compartmentalization! They organize the information source (DNA) into nucleus, making it efficient to read and copy. They put all energy forming apparatus into units called mitochondria. They organize garbage disposal into chambers called lysosomes. But the beauty and complexity of biological systems doesn't stop there! They go one step further and aggregate developmentally important and dynamic stuff into structures that lack a membranous boundary; essentially packaging biological entities without an overt packet!

How do they achieve such a feat. Shamba and colleagues try to answer this question by looking at the formation of germline defining particles, the P-bodies, in a worm, C. elegans. These non-membranous compartment, they find, are generated by an striking process called phase-separation, just like oil droplets form when mixed with water! But these bodies are much more than passive emulsions, and are a complex mix of RNA and protein dynamically interacting with the surroundings!! What is even more striking, and beautiful, is that these do not form randomly, but are localized to one area of the cell. How many components are needed to make such a complex biological process?? Listen to Shamba to know that the real beauty in the system is its simplicity, as only one (ONE!!!) protein is enough to generate these structures, and a very small network to regulate it.



To know more about the work, please refer to the following publication:
Polar Positioning of Phase-Separated Liquid Compartments in Cells Regulated by an mRNA Competition Mechanism
Saha et al., Cell. Volume 166, Issue 6, p1572–1584.

Also, you can see a video abstract on the topic here:
Phase separation in cell polarity
  

A morphing traveler. Interview with Mohit Jolly on identity changes during metastasis!

Cancer cells evade foreign tissues during metastasis. This process is most critical phase of cancer development, since it decreases a successful prognostics drastically. During the invasion process, the cells change their characteristics, acquiring different shapes, cell identity and lineage. How this is regulated still remains open question, and vital to developing a cure for the disease.

Mohit and colleagues take an integrated theoretical-experimental approach to understand how sarcomas spread. Sacromas arise from connective tissues, like bone or fat. And while traveling long distances they undergo a change into more epithelial like identity. This plasticity helps the cells survive better in the the body. To more more about such transition, please listen to the interview with Mohit.



For more information, please refer to:
Mesenchymal-epithelial transition in sarcomas is controlled by the combinatorial expression of miR-200s and GRHL2
Somarelli et al., Molecular and Cellular Biology, 2016