Polycomb group (PcG) proteins are essential for accurate axial body patterning during embryonic development. PcG-mediated repression is conserved in metazoans and is targeted in Drosophila by Polycomb response elements (PREs). However, targeting sequences in humans have not been described. While analyzing chromatin architecture in the context of human… (More)
The production of high-affinity protective antibodies requires somatic hypermutation (SHM) of the antibody variable (V)-region genes. SHM is characterized by a high frequency of point mutations that occur only during the centroblast stage of B-cell differentiation. Activation-induced cytidine deaminase (AID), which is expressed specifically in… (More)
Huntington's disease (HD) is caused by expansion of the polymorphic polyglutamine segment in the huntingtin protein. Full-length huntingtin is thought to be a predominant HEAT repeat alpha-solenoid, implying a role as a facilitator of macromolecular complexes. Here we have investigated huntingtin's domain structure and potential intersection with epigenetic… (More)
It is not clear to what extent noncoding RNAs regulate the homeobox (HOX) genes that encode key regulators of development in the embryo. In this issue, Rinn et al. (2007) characterize noncoding RNAs that regulate HOX genes and discover one, HOTAIR, that unexpectedly regulates a HOX gene cluster on a different chromosome than the HOX cluster that encodes it.
Polycomb Group (PcG)-mediated repression is critical for cell fate determination and maintenance of gene expression during embryonic development. However, the mechanisms underlying PcG recruitment in mammals remain unclear since few regulatory sites have been identified. We have identified and characterized two new potential PcG-dependent regulatory… (More)