May have an important role in defining the spacing of the nuclear envelope lumen. Essential for centrosome attachment to the nucleus; maintenance of correct ploidy; proper mitosis; association of the centromere cluster with the centrosome and the maintenance of genome stability. Requires direct chromatin binding for inner nuclear membrane targeting. {ECO:0000269|PubMed:18266910; ECO:0000269|PubMed:19632001}.