Inner nuclear membrane protein

[4] Lamins and chromatin found at the nuclear envelope are organised with the assistance of proteins embedded in the INM.

[6] and help to repress gene expression, both by tethering specific genomic regions to the nuclear periphery, and by interaction with histone deacetylase (HDAC) 3.

[4] It has been proposed that chromatin-binding/modifying proteins embedded within the inner nuclear membrane may be central in determining the identity of newly differentiated cells.

The nucleoplasmic domains of such proteins can interact with chromatin to create a scaffold and restrict the conformation of chromosomes within three dimensions.

When such a signal changes expression of genes coding for INM or a chromatin-modifying enzymes, it can induce differentiation in to a different cell type.

Some cells that are very closely related may have similar INMs, but transient changes in expression—e.g., in response to extracellular signals—could possibly lead to more permanent changes in expression profile by altering transcription rates for chromatin modifying enzymes, transcriptional modulators, or other regulatory proteins.

Posttranslational modifications of INM proteins play a critical role in their functional modulation.

[12] The wide array of diseases involving lamins and their associated inner nuclear membrane proteins are collectively called laminopathies.

[13] Mutations in the gene EDM, encoding the INM protein emerin may be the cause of X-linked Emery–Dreifuss muscular dystrophy.

[2] As mutations in lamins cause the autosomal dominant form of Emery–Dreifuss muscular dystrophy, and lamins and emerin are known to interact, it has been hypothesised that muscle disease is caused by a structural defect in the nuclear envelope brought on by dysfunction in one of these proteins.