First published online January 11, 2008
Development 135, 301e (2008)
© The Company of Biologists Limited
Radical ECM changes at fertilization
When an animal egg is fertilized, the zygote rapidly transforms the
extracellular matrix (ECM) of the egg into a protective structure in which
embryogenesis can proceed. On p.
431, Wong and Wessel provide new insights into the biochemistry of
this important transformation in the sea urchin fertilization envelope. Soon
after insemination, they report, the fertilization envelope becomes
impermeable to molecules larger than 40,000 daltons (medium-sized proteins;
for example, serum albumin) via a peroxidase-dependent protein crosslinking
mechanism. Using a new in vivo technique to label and isolate the modified ECM
components, they show that four major components of the fertilization envelope
are selectively crosslinked in a manner that distinguishes between protein
isoforms derived from the same gene. The authors speculate that this
selectivity is partly due to the local clustering of target proteins within
the fertilization envelope and conclude that the free-radical crosslinking of
specific proteins is essential for establishing the embryonic microenvironment
that is needed for early development.
Related articles in Development:
- Free-radical crosslinking of specific proteins alters the function of the egg extracellular matrix at fertilization
- Julian L. Wong and Gary M. Wessel
Development 2008 135: 431-440.
[Abstract]
[Full Text]
