Heart Development: Gene Control

Abstract

All creatures from flies to humans possess a heart‐like contractile organ responsible for movement of fluid through the body. Molecular studies have revealed a remarkable degree of evolutionary conservation in the genetic pathways underlying heart development. In Drosophila , the transcription regulatory proteins TINMAN , PANNIER , MEF2 , plus members of the TBX and HAND families are required for regulation of heart muscle differentiation and correct morphogenesis of the heart. Expression of the cardiac transcription factors is regulated by growth factor signalling from adjacent tissues. In vertebrates, members of precisely the same transcription factor families are required for heart development and their expression is also subject to growth factor regulation. One major difference is that higher organisms usually express several members of each protein family, leading to at least partial functional redundancy. In both flies and mammals, several distinct transcription regulatory proteins interact both genetically and physically to precisely regulate transcription of the structural, morphological and physiological genes required for establishment of correct heart structure and function. Key Concepts: The transcription regulatory system required for development of the heart involves members of several distinct transcription factor families. Interactions between a number of distinct transcription factors are essential for gene regulatory function. Genetic regulation of heart development is evolutionarily conserved.