Jeffrey Farrell, a researcher from the National Institute of Child Health and Human Development, presented his research on zebrafish cell development Nov. 2 as part of the biology department seminar series.
Farrell’s research on zebrafish cell differentiation and specialization maps out how genetically identical body cells specialize their appearances and functions by activating certain genes. His work takes advantage of recent technological advances in biology to map out the evolution of cells in the fish.
“You have muscle cells that are specialized for contraction. You have cells in your retina — photoreceptors — that are specialized for detecting light,” Farrell told The Hoya. “The same DNA is in essentially all of those cells. But then there are differences where they use some of those instructions and not others that make them into a blood cell or make them into a photoreceptor.”
Mark Rose, chair of the department of biology, said that the use of zebrafish as an animal model allows Farrell’s research on smooth muscle tissues that comprise the liver, stomach and other internal organs to be applied to human biology.
“In zebrafish, the reason people use it is because it’s a vertebrate, and it turns out the genetics is much, much more powerful than a mouse’s,” Rose told The Hoya. “Developments in the study and what they learned there about smooth muscle cells is relevant to the way smooth muscle cells arise in humans.”
Rose said Farrell’s research presents new mechanisms for classifying cells more accurately and pinpointing their specific functions based on genetic markers.
“The development of the smooth muscle was really unclear. We’ve heard of these two different kinds of longitudinal and axial muscle cells. They had not really been teased apart, not all was known about them,” Rose said. “Farrell could show with his analysis that not only were there two different cells, but also that their gene expression profiles had unique traits.”
Eric Glasgow, an assistant professor in the oncology department at the Georgetown University School of Medicine who is doing his own research on zebrafish, said that Farrell has leveraged modern technology to read numerous gene sequences, in the form of RNA transcripts, to help determine the cell’s physical characteristics.
“Can we look at all the different RNA transcripts that are being made? That’s a lot of sequencing, and a lot of computation because you have a lot of sequences that are going to represent every RNA being expressed,” Glasgow told The Hoya. “And that’s really the computational side of Farrell’s research — taking that massive amount of data and then being able to use it to follow the fates of individual cells.”
Glasgow said that Farrell’s discoveries could be applied to cancer research through a new understanding of cell classifications, especially of cells important for signaling such as intestinal communicators.
“The most interesting translational aspect was the new cell type in the intestine. It’s a signaling cell that receives and passes on information. Those types of cells tend to be very important for cancer development,” Glasgow said. “We can now make models and modify what’s going on in that cell, which might affect colon cancer and its outcome.”
Farrell said he believes that modern technology enables his high output of data and is enthusiastic about future research.
“The scale at which we are able to do things in biology has changed dramatically in the last decade. We have all these predictions about the signals and what individual genes are important for gut cell behavior,” Farrell said. “Increases in technology, miniaturization and computational ability have enabled the scale in biology that was difficult to achieve before.”
Farrell’s tracing of cell specialization is one example of technology advancement that has cut the time required for new developments.
“That’s the kind of thing that now two of us researchers in a lab can come up with in the span of a couple of years, but it used to be the kind of thing that took entire teams of researchers multiple decades to do,” Farrell added.