Highly read on jcb.rupress.org 11 Dec–10 Jan

A type of programmed cell death called apoptosis has been imaged in live mouse embryos, providing insight into a developmental process that can go awry and cause neural birth defects.

Yoshifumi Yamaguchi and Masayuki Miura at the University of Tokyo and their team engineered mice that generate a fluorescent signal in response to the activation of caspases, enzymes that trigger apoptosis. The authors used a fast-scanning confocal microscope to detect this activation in developing mouse embryos at single-cell resolution. They also conducted time-lapse imaging of an early-developmental process called neural-tube closure — in which apoptosis occurs and the basic structure of the central nervous system is formed.

In embryos that were missing key apoptotic genes, this closure process occurred much more slowly and, in some embryos, even failed to complete. The authors suggest that neural-tube closure must occur within a specific time window to be completed properly.

J. Cell Biol. 195, 1047–1060 (2011)