Send to

Choose Destination
Biochem Biophys Res Commun. 2003 Jan 10;300(2):391-6.

Point mutations in BCL6 DNA-binding domain reveal distinct roles for the six zinc fingers.

Author information

INSERM U309, Institut Albert Bonniot, Domaine de la Merci, 38706 La Tronche Cedex, France.


The B-cell lymphoma 6 (BCL6) gene encodes a transcriptional repressor containing six C-terminal Kr├╝ppel-like zinc fingers. The zinc finger (ZF) cluster is necessary and sufficient for interaction with both DNA and several proteins and for nuclear targeting. However, the functional specificity of the six ZFs in these cellular roles is unknown. To characterize this domain, we mutated individually each ZF of BCL6. Our results reveal that mutation of the two N-terminal ZFs does not impair cognate DNA-binding, cellular localization of the protein nor the transcriptional repression capacity of BCL6. By contrast, mutation of any of the remaining ZFs abolishes the binding of BCL6 to DNA in vitro and the transrepressive function of the protein in vivo. Finally, none of the six mutations affect the interaction between BCL6 and class II histone deacetylases. Thus our experiments demonstrate that BCL6 uses each of the four C-terminus ZFs for binding to a target sequence while the two amino terminal fingers are likely engaged in other unknown function(s).

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science Icon for HAL archives ouvertes
Loading ...
Support Center