Marie Kmita Team Finds 2 Polycomb Complexes Drive Embryo Limb Formation
Updated
Updated · Université de Montréal · Jun 2
Marie Kmita Team Finds 2 Polycomb Complexes Drive Embryo Limb Formation
2 articles · Updated · Université de Montréal · Jun 2
Summary
PNAS-published work from Université de Montréal and IRCM shows PRC1 and PRC2 act as genetic brakes, shutting off early limb-building genes once they have launched embryonic development.
Mouse experiments showed disrupting one Polycomb system already distorted gene expression, while disabling both left early genes stuck on and severely impaired normal limb formation.
The finding explains a key timing mechanism in embryonic development: genes that start limb formation must be rapidly silenced so later genetic programs can take over.
Marie Kmita's team says the result sharpens understanding of how embryos build limbs correctly by coordinating sequential waves of gene activity.
If scientists have found the 'genetic brakes' for birth defects, what causes them to fail during pregnancy?
Does the 'genetic brake' that builds our limbs also hold the secret to how animals evolved wings and fins?
Genetic Brakes in Action: Polycomb Complexes Orchestrate Limb Development and Safeguard Against Birth Defects
Overview
Dr. Marie Kmita's team has made a major discovery about how embryonic limbs form. Their research shows that Polycomb protein complexes, PRC1 and PRC2, act as precise genetic brakes. These complexes use chromatin-modifying activities to silence genes at the right developmental stages, which prevents errors that could cause congenital abnormalities. Importantly, cells not only need to turn on the correct genes but also remember which ones must stay off. This careful gene control is essential for healthy development, highlighting the crucial role of Polycomb complexes in ensuring proper limb formation.