Emerin is an integral protein of the inner nuclear membrane. In humans, loss of emerin causes the X-linked form of Emery-Dreifuss muscular dystrophy. The emerin gene (
emr-1 ) is conserved in C. elegans . We show that Ce-emerin protein is expressed ubiquitously in C. elegans , and that Ce-emerin localization at the nuclear envelope requires the C. elegans lamin protein, Ce-lamin. We determined the loss-of-function phenotype for emerin in C. elegans , by double-stranded RNA inhibition (RNAi) of the
emr-1 gene. In embryos lacking Ce-emerin, we detected normal nuclear envelope localization for Ce-lamin, UNC-84, nucleoporins and Ce-MAN1, which is related to emerin through the conserved LEM-domain. The RNAi-induced loss of Ce-emerin had no apparent effects on development, since Ce-emerin-deficient embryos developed normally into fertile adult nematodes. Furthermore, the RNAi-induced loss of emerin persisted into adulthood, with no detectable phenotype. Based on its lamin-dependent localization at the nuclear envelope, biochemical properties and non-essential phenotype, Ce-emerin closely resembles human emerin. These findings establish C. elegans as a suitable genetic organism in which to dissect the molecular mechanisms of emerin function in vivo .