LAP1 interactome profiling provides new insights into LAP1’s physiological functions

The nuclear envelope (NE), a protective membrane bordering the nucleus, is composed of highly specialized proteins that are indispensable for normal cellular activity. Lamina-associated polypeptide 1 (LAP1) is a NE protein whose functions are just beginning to be unveiled. The fact that mutations causing LAP1 deficiency are extremely rare and pathogenic is indicative of its paramount importance to preserve human health, anticipating that LAP1 might have a multifaceted role in the cell. Mapping the LAP1 protein interactome is, thus, imperative to achieve an integrated view of its potential biological properties. To this end, we employed in silico- and mass spectrometry-based approaches to identify candidate LAP1-interacting proteins, whose functional attributes were subsequently characterized using bioinformatics tools. Our results suggest that LAP1 may participate in cellular processes as diverse as chromatin and cytoskeleton organization, DNA repair, RNA processing, translation as well as protein biogenesis and turnover. Novel interactions between LAP1 and DNA repair proteins were additionally validated, strengthening the previously proposed involvement of LAP1 in the maintenance of genomic stability. Overall, the data presented in this study reaffirm the biological relevance of LAP1 and the need to deepen our knowledge about this NE protein, providing new insights that will help guiding future research towards a mechanistic understanding of LAP1’s functioning.