"For the first time, this nails it," said Sharon Amacher, professor of molecular genetics at Ohio State University and lead author of the study.
"This provides the data that cells with disabled Notch signaling can oscillate just fine, but what they can't do is synchronize with their neighbors."
The imaging also allowed Amacher
and colleagues to determine that cell division, called mitosis, is not a random event as was once believed.
"This early process of segmentation is really important for patterning a lot of subsequent developmental events-the patterning of the nervous system and the vasculature, much of that depends on this clock ensuring that early development happens properly," Amacher
, Delaune and Shih conducted the research while at the University of California, Berkeley
Amacher joined the Ohio State faculty in July.
The resulting short-lived fluorescent fusion protein allowed Amacher
and colleagues to look at single cells along with their neighbors to observe how they stayed synchronized as they did the wave.
Researchers in this field had previously thought that the Notch signaling pathway may be needed to start the clock in these cyclic genes, though conflicting data had shown that the clock could run without the signal.
imaging showed that, indeed, Notch was required only to maintain synchronization, but not to start the oscillating clock.
and colleagues tested this idea by combining the imaging tool with three mutant cell types with disabled Notch signals.
said these findings could be incorporated into models of developmental cell behavior to further advance cell biology research.