Nuclear envelope proteins and associated diseases.

There is a growing body of evidence in favour of the presence of human diseases caused by mutations in genes that encode the nuclear envelope proteins emerin and lamin A/C (lamin A and C are alternatively spliced variants of the same gene). Emerin deficiency results in X-linked Emery-Dreifuss muscular dystrophy (EDMD). Lamin A/C mutations cause the autosomal-dominant form of EDMD, limb-girdle muscular dystrophy with atrioventricular conduction disturbances (type 1B), hypertrophic cardiomyopathy and Dunnigan-type familial partial lipodystrophy. In the targeted mouse model of lamin A gene deficiency, loss of lamin A/C is associated with mislocalization of emerin. Thus, one plausible pathomechanism for EDMD, limb-girdle muscular dystrophy type 1B, hypertrophic cardiomyopathy and familial partial lipodystrophy is the presence of specific abnormalities of the nuclear envelope. Therefore, a group of markedly heterogeneous disorders can be classified as 'nuclear envelopathies'. The present review summarizes recent findings on nuclear envelope proteins and diseases.