RNA sequencing of mouse sinoatrial node reveals an upstream regulatory role for Islet-1 in cardiac pacemaker cells

Circ Res. 2015 Feb 27;116(5):797-803. doi: 10.1161/CIRCRESAHA.116.305913. Epub 2015 Jan 26.


Rationale: Treatment of sinus node disease with regenerative or cell-based therapies will require a detailed understanding of gene regulatory networks in cardiac pacemaker cells (PCs).

Objective: To characterize the transcriptome of PCs using RNA sequencing and to identify transcriptional networks responsible for PC gene expression.

Methods and results: We used laser capture microdissection on a sinus node reporter mouse line to isolate RNA from PCs for RNA sequencing. Differential expression and network analysis identified novel sinoatrial node-enriched genes and predicted that the transcription factor Islet-1 is active in developing PCs. RNA sequencing on sinoatrial node tissue lacking Islet-1 established that Islet-1 is an important transcriptional regulator within the developing sinoatrial node.

Conclusions: (1) The PC transcriptome diverges sharply from other cardiomyocytes; (2) Islet-1 is a positive transcriptional regulator of the PC gene expression program.

Keywords: Hcn4 protein, mouse; Isl1 protein, mouse; high-throughput RNA sequencing; laser capture microdissection; sinoatrial node; transcription factors.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Video-Audio Media

MeSH terms

  • Animals
  • Female
  • Fetal Heart / cytology
  • Gene Expression Profiling
  • Gene Expression Regulation, Developmental*
  • Gene Regulatory Networks
  • Genes, Reporter
  • Heart Atria / cytology
  • Heart Atria / embryology
  • Heart Atria / metabolism
  • High-Throughput Nucleotide Sequencing
  • LIM-Homeodomain Proteins / deficiency
  • LIM-Homeodomain Proteins / genetics
  • LIM-Homeodomain Proteins / physiology*
  • Laser Capture Microdissection
  • Male
  • Mice
  • Molecular Sequence Data
  • Myocardial Contraction
  • Myocytes, Cardiac / metabolism*
  • RNA, Messenger / biosynthesis*
  • RNA, Messenger / genetics
  • RNA, Messenger / isolation & purification
  • Sinoatrial Node / cytology*
  • Sinoatrial Node / embryology
  • Sinoatrial Node / metabolism
  • Subtraction Technique
  • Transcription Factors / deficiency
  • Transcription Factors / genetics
  • Transcription Factors / physiology*
  • Transcription, Genetic
  • Transcriptome


  • LIM-Homeodomain Proteins
  • RNA, Messenger
  • Transcription Factors
  • insulin gene enhancer binding protein Isl-1