Setleis syndrome: Clinical, molecular and structural studies of the first TWIST2 missense mutation.

Setleis syndrome: Clinical, molecular and structural studies of the first TWIST2 missense mutation.
Clin Genet. 2014 Nov 19;
Authors: Rosti RO, Uyguner ZO, Nazarenko I, Bekerecioglu M, Cadilla CL, Ozgur H, Lee BH, Aggarwal AK, Pehlivan S, Desnick RJ
Abstract
Setleis syndrome is characterized by bitemporal scar-like lesions and other characteristic facial features. It results from recessive mutations that truncate critical functional domains in the basic helix-loop-helix (bHLH) transcription factor, TWIST2, which regulates expression of genes for facial development. To date, only four nonsense or small deletion mutations have been reported. In the current report, the clinical findings in a consanguineous Turkish family were characterized. Three affected siblings had the characteristic features of Setleis syndrome. Homozygosity for the first TWIST2 missense mutation, c.326T>C (p.Leu109Pro), was identified in the patients. In silico analyses predicted that the secondary structure of the mutant protein was sustained, but the empirical force field energy increased to an unfavorable level with the proline substitution (p.Leu109Pro). On a crystallographically generated dimer, p.Leu109 lies near the dimer interface, and the proline substitution is predicted to hinder dimer formation. Therefore, p.Leu109Pro-TWIST2 alters the three dimensional structure and is unable to dimerize, thereby hindering the binding of TWIST2 to its target genes i...

Source: Clinical Genetics - November 19, 2014 Category: Genetics & Stem Cells Authors: Rosti RO, Uyguner ZO, Nazarenko I, Bekerecioglu M, Cadilla CL, Ozgur H, Lee BH, Aggarwal AK, Pehlivan S, Desnick RJ Tags: Clin Genet Source Type: research