RT Journal Article
SR Electronic
T1 Species-specific segmentation clock periods are due to differential biochemical reaction speeds
JF Science
JO Science
FD American Association for the Advancement of Science
SP 1450
OP 1455
DO 10.1126/science.aba7668
VO 369
IS 6510
A1 Matsuda, Mitsuhiro
A1 Hayashi, Hanako
A1 Garcia-Ojalvo, Jordi
A1 Yoshioka-Kobayashi, Kumiko
A1 Kageyama, Ryoichiro
A1 Yamanaka, Yoshihiro
A1 Ikeya, Makoto
A1 Toguchida, Junya
A1 Alev, Cantas
A1 Ebisuya, Miki
YR 2020
UL http://science.sciencemag.org/content/369/6510/1450.abstract
AB Many animals display similarities in their organization (body axis, organ systems, and so on). However, they can display vastly different life spans and thus must accommodate different developmental time scales. Two studies now compare human and mouse development (see the Perspective by Iwata and Vanderhaeghen). Matsuda et al. studied the mechanism by which the human segmentation clock displays an oscillation period of 5 to 6 hours, whereas the mouse period is 2 to 3 hours. They found that biochemical reactions, including protein degradation and delays in gene expression processes, were slower in human cells compared with their mouse counterparts. Rayon et al. looked at the developmental tempo of mouse and human embryonic stem cells as they differentiate to motor neurons in vitro. Neither the sensitivity of cells to signals nor the sequence of gene-regulatory elements could explain the differing pace of differentiation. Instead, a twofold increase in protein stability and cell cycle duration in human cells compared with mouse cells was correlated with the twofold slower rate of human differentiation. These studies show that global biochemical rates play a major role in setting the pace of development.Science, this issue p. 1450, p. eaba7667; see also p. 1431Although mechanisms of embryonic development are similar between mice and humans, the time scale is generally slower in humans. To investigate these interspecies differences in development, we recapitulate murine and human segmentation clocks that display 2- to 3-hour and 5- to 6-hour oscillation periods, respectively. Our interspecies genome-swapping analyses indicate that the period difference is not due to sequence differences in the HES7 locus, the core gene of the segmentation clock. Instead, we demonstrate that multiple biochemical reactions of HES7, including the degradation and expression delays, are slower in human cells than they are in mouse cells. With the measured biochemical parameters, our mathematical model accounts for the two- to threefold period difference between the species. We propose that cell-autonomous differences in biochemical reaction speeds underlie temporal differences in development between species.