Difference between revisions of "Part:BBa J176000"

Revision as of 05:32, 3 July 2011

hPCD

Polycomb chromodomain (PCD) from the human CBX8 protein (a.a. 1-63).
Other names: KAH01

Usage and Biology

Drosophila PCD Crystal structure reported by Fischle et al. 2003

The Polycomb chromodomain (PCD) is a protein sequence motif that is conserved in many multicellular organisms. The motif appears in proteins involved in regulating tissue identity, including the Drosophila (fruit fly) Pc protein, and the vertebrate Chromobox (CBX) protein family. PCD has an aromatic pocket that specifically recognizes the unfolded "tail" of histone H3 when the histone is trimethylated at lysine 27. The crystal structure has been solved for the Drosophila melanogaster (fruit fly) variant this peptide (see figure below) (Fischle et al., 2003; see also Min et al., 2003).

In its native context, the PCD targets gene silencing proteins to genes marked with histone methylation. The PCD domain can be fused to Biobrick proteins to recruit other protein domains, such as synthetic transcriptional activators, to sites of histone methylation in human cells (Haynes and Silver, 2011).

REFERENCES:

1. Fischle, W, Wang, Y, Jacobs, SA, Kim, Y, Allis, CD, Khorasanizadeh, S. (2003) Molecular basis for the discrimination of repressive methyl-lysine marks in histone H3 by Polycomb and HP1 chromodomains. Genes Dev. 17:1870-1881.
2. Min, J, Zhang, Y, Xu, RM. (2003) Structural basis for the specific binding of Polycomb chromodomain to histone H3 methylated at Lys 27. Genes Dev. 17:1823-1828.
3. Haynes, KA, Silver, PA. (2011) Synthetic reversal of epigenetic silencing. J Biol Chem. E-pub ahead of print.

Sequence and Features