A lamin B receptor in the nuclear envelope.

HJ Worman, J Yuan, G Blobel… - Proceedings of the …, 1988 - National Acad Sciences
HJ Worman, J Yuan, G Blobel, SD Georgatos
Proceedings of the National Academy of Sciences, 1988National Acad Sciences
Using a solution binding assay, we show that purified 125I-labeled lamin B binds in a
saturable and specific fashion to lamin-depleted avian erythrocyte nuclear membranes with
a Kd of approximately 0.2 microM. This binding is significantly greater than the binding of
125I-labeled lamin A and is competitively inhibited by unlabeled ligand. We demonstrate
that a 58-kDa integral membrane protein (p58) is a lamin B receptor by virtue of its
abundance in the nuclear envelope and association with 125I-labeled lamin B in ligand …
Using a solution binding assay, we show that purified 125I-labeled lamin B binds in a saturable and specific fashion to lamin-depleted avian erythrocyte nuclear membranes with a Kd of approximately 0.2 microM. This binding is significantly greater than the binding of 125I-labeled lamin A and is competitively inhibited by unlabeled ligand. We demonstrate that a 58-kDa integral membrane protein (p58) is a lamin B receptor by virtue of its abundance in the nuclear envelope and association with 125I-labeled lamin B in ligand blotting assays. Specific antibodies raised against p58 recognize one protein in isolated nuclei and partially block 125I-labeled lamin B binding to lamin-depleted nuclear membranes. Cell fractionation and indirect immunofluorescence microscopy show that p58 is located in the periphery of the nucleus. This protein may serve as a membrane attachment site for the nuclear lamina by acting as a specific receptor for lamin B.
National Acad Sciences