First published online October 12, 2006
Development 133, 2104e (2006)
© The Company of Biologists Limited
A new player in patterning by proteolysis
The transition from egg to embryo in C. elegans involves
fertilisation, meiosis, exit from meiosis and the establishment of the
anteroposterior (AP) axis. These last two processes may be connected - many
mutants with meiotic defects, including several that affect ubiquitin-mediated
proteolysis, have polarity defects. Now, Bruce Bowerman and colleagues report
that PAM-1, a puromycin-sensitive aminopeptidase that might act in conjunction
with the proteasome to degrade ubiquitin-tagged proteins, is required for both
meiotic exit and AP polarity in one-cell worm embryos (see
p. 4281). The
researchers show that meiotic exit is delayed and the AP axis is not specified
in pam-1 mutants. As inactivation of the B-type cyclin CYB-3 rescues
the first (but not the second) of these defects, PAM-1 may regulate CYB-3
during meiotic exit but presumably targets other proteins to regulate
polarity. The researchers conclude that PAM-1 contributes to the proteolytic
machinery that triggers cell-cycle progression and the establishment of AP
polarity in the early worm embryo, and possibly in other embryos.
Related articles in Development:
- The puromycin-sensitive aminopeptidase PAM-1 is required for meiotic exit and anteroposterior polarity in the one-cell Caenorhabditis elegans embryo
- Rebecca Lyczak, Lynnsey Zweier, Thomas Group, Mary Ann Murrow, Christine Snyder, Lindsay Kulovitz, Alexander Beatty, Kristen Smith, and Bruce Bowerman
Development 2006 133: 4281-4292.
[Abstract]
[Full Text]
