Cells trade information
with adjoining cells and, like the telephone game,
the original
message becomes garbled the further it travels down the line.
(January 21, 2016) To
decide whether and where to move in the body, cells must read chemical signals
in their environment. Individual cells do not act alone during this process,
two new studies on mouse mammary tissue show. Instead, the cells make decisions
collectively after exchanging information about the chemical messages they are
receiving.
“Cells talk to nearby cells and compare notes before they
make a move,” says Ilya Nemenman, a theoretical biophysicist at Emory
University and a co-author of both studies, published by the Proceedings of the
National Academy of Sciences (PNAS). The co-authors also include scientists
from Johns Hopkins, Yale and Purdue.
The researchers discovered that the cell communication
process works similarly to a message relay in the telephone game. “Each cell
only talks to its neighbor,” Nemenman explains. “A cell in position one only
talks to a cell in position two. So position one needs to communicate with
position two in order to get information from the cell in position three.”
And like the telephone game – where a line of people whisper
a message to the person next to them – the original message starts to become
distorted as it travels down the line. The researchers found that, for the
cells in their experiments, the message begins to get garbled after passing
through about four cells, by a factor of about three.
“We built a mathematical model for this linear relay of
cellular information and derived a formula for its best possible accuracy,”
Nemenman says. “Directed cell migration is important in processes from cancer
to the development of organs and tissues. Other researchers can apply our model
beyond the mouse mammary gland and analyze similar phenomena in a wide variety
of healthy and diseased systems.”