Crystal structure of the PB1 domain of NBR1.

EMBL-Hamburg Outstation, c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany.
FEBS Letters (Impact Factor: 3.34). 02/2006; 580(1):341-4. DOI: 10.1016/j.febslet.2005.12.021
Source: PubMed

ABSTRACT The scaffold protein NBR1 is involved in signal transmission downstream of the serine/protein kinase from the giant muscle protein titin. Its N-terminal Phox and Bem1p (PB1) domain plays a critical role in mediating protein-protein interactions with both titin kinase and with another scaffold protein, p62. We have determined the crystal structure of the PB1 domain of NBR1 at 1.55A resolution. It reveals a type-A PB1 domain with two negatively charged residue clusters. We provide a structural perspective on the involvement of NBR1 in the titin kinase signalling pathway.

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