Int. J. Dev. Biol. 53: 909 - 924 (2009)

https://doi.org/10.1387/ijdb.082747rb

Vol 53, Issue 7

A twist of insight - the role of Twist-family bHLH factors in development

Open Access | Review | Published: 6 April 2009

Ralston M. Barnes and Anthony B. Firulli*

Riley Heart Research Center, Wells Center for Pediatric Research, Division of Pediatric Cardiology, Departments of Anatomy and Medical and Molecular Genetics, Indiana Medical School, Indianapolis, IN, USA

Abstract

Members of the Twist-family of bHLH proteins play a pivotal role in a number of essential developmental programs. Twist-family bHLH proteins function by dimerizing with other bHLH members and binding to cis- regulatory elements, called E-boxes. While Twist-family members may simply exhibit a preference in terms of high-affinity binding partners, a complex, multilevel cascade of regulation creates a dynamic role for these bHLH proteins. We summarize in this review information on each Twist-family member concerning expression pattern, function, regulation, downstream targets, and interactions with other bHLH proteins. Additionally, we focus on the phospho-regulatory mechanisms that tightly control posttranslational modification of Twist-family member bHLH proteins.

Keywords

Twist1, Twist2, Hand1, Hand2, Paraxis, Scleraxis, limb, heart, trophoblast, phosphoregulation, dimerization