Tohoku J. Exp. Med., 2018 March, 244(3)

Review

Shox2: The Role in Differentiation and Development of Cardiac Conduction System

WENYU HU,1 YANGUO XIN,2 YINAN ZHAO3 and JIAN HU1

1Department of Cardiology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
2Department of Cardiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China
3Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China

The formation and conduction of electrocardiosignals and the synchronous contraction of atria and ventricles with rhythmicity are both triggered and regulated by the cardiac conduction system (CCS). Defect of this system will lead to various types of cardiac arrhythmias. In recent years, the research progress of molecular genetics and developmental biology revealed a clearer understanding of differentiation and development of the cardiac conduction system and their regulatory mechanisms. Short stature homeobox 2 (Shox2) transcription factor, encoded by Shox2 gene in the mouse, is crucial in the formation and differentiation of the sinoatrial node (SAN). Shox2 drives embryonic development processes and is widely expressed in the appendicular skeleton, palate, temporomandibular joints, and heart. Mutations of Shox2 can lead to dysembryoplasia and abnormal phenotypes, including bradycardiac arrhythmia. In this review, we provide a summary of the latest research progress on the regulatory effects of the Shox2 gene in differentiation and development processes of the cardiac conduction system, hoping to deepen the knowledge and understanding of this systematic process based on the cardiac conduction system. Overall, the Shox2 gene is intimately involved in the differentiation and development of cardiac conduction system, especially sinoatrial node. We also summarize the current information about human SHOX2. This review article provides a new direction in biological pacemaker therapies.

Key words —— arrhythmia; cardiac conduction system; differentiation; heart evelopment; Shox2

===============================

Tohoku J. Exp. Med., 2018, 244, 177-186

Correspondence: Yinan Zhao, Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, China.

e-mail: zhaoyinan1616@yahoo.co.jp