The R482Q lamin A/C mutation that causes lipodystrophy does not prevent nuclear targeting of lamin A in adipocytes or its interaction with emerin

I Holt, L Clements, S Manilal, SC Brown… - European Journal of …, 2001 - nature.com
I Holt, L Clements, S Manilal, SC Brown, GE Morris
European Journal of Human Genetics, 2001nature.com
Most pathogenic missense mutations in the lamin A/C gene identified so far cause
autosomal-dominant dilated cardiomyopathy and/or Emery-Dreifuss muscular dystrophy. A
few specific mutations, however, cause a disease with remarkably different clinical features:
FPLD, or familial partial lipodystrophy (Dunnigan-type), which mainly affects adipose tissue.
We have prepared lamin A with a known FPLD mutation (R482Q) by in vitro mutagenesis.
Nuclear targeting of lamin A in transfected COS cells, human skeletal muscle cells or mouse …
Abstract
Most pathogenic missense mutations in the lamin A/C gene identified so far cause autosomal-dominant dilated cardiomyopathy and/or Emery-Dreifuss muscular dystrophy. A few specific mutations, however, cause a disease with remarkably different clinical features: FPLD, or familial partial lipodystrophy (Dunnigan-type), which mainly affects adipose tissue. We have prepared lamin A with a known FPLD mutation (R482Q) by in vitro mutagenesis. Nuclear targeting of lamin A in transfected COS cells, human skeletal muscle cells or mouse adipocyte cell cultures (pre-and post-differentiation) was not detectably affected by the mutation. Quantitative in vitro measurements of lamin A interaction with emerin using a biosensor also showed no effect of the mutation. The results show that the loss of function of R482 in lamin A/C in FPLD does not involve loss of ability to form a nuclear lamina or to interact with the nuclear membrane protein, emerin.
nature.com