Tuesday, June 16, 2015

Muscle disease's genetic cause explored

Scimex: New Zealand, Australian and Dutch scientists have found out how a specific molecule switches on and off the genes that play a role in the muscle disease Facioscapulohumeral Muscular Dystrophy. The authors say that this information will help them understand how the molecule works normally and therefore how it fails to work in people with the disease.

Structural maintenance of chromosomes flexible hinge domain containing 1 (Smchd1) is a protein that plays an important role in maintaining gene silencing in many biological circumstances, including facioscapulohumeral muscular dystrophy; however, how it brings about gene silencing is unknown. Understanding the molecular mechanism by which Smchd1 contributes to stable transcriptional silencing is critical to appreciate how it functions in normal biology and when it is mutated in facioscapulohumeral muscular dystrophy. This study reveals, for the first time to our knowledge, where Smchd1 binds genome-wide, its hitherto unappreciated functional interaction with chromatin organizer CCCTC-binding factor in gene regulation, and which part of the protein is required for chromatin binding. These data lead to a new model of Smchd1 function, where it directly binds DNA to mediate 3D chromatin architecture.