Table 1

Some examples of key transcription factors expressed in the heart

FactorGene familyDNA binding siteExpression patternExamples of gene regulated
α-MHC, cardiac α myosin heavy chain; ANF, atrial natriuretic factor; bHLH, basic helix-loop-helix; CK-M, muscle creatine kinase; HIF-1, hypoxia inducible factor-1; MEF-2, myocyte enhancer factor-2; MLC2v, ventricular myosin light chain 2; SM22, smooth muscle 22; SRF, serum response factor; TnIc, cardiac troponin I; TnC, troponin C.
MEF-2 A, B, C, D4MADS box familyCTA(A/T)4TAGWidely expressedTnIc CK-M
SRF5MADS box familyCC(A/T)6GG (“AcrG box”)Widely expressedα-cardiac actin, SM22, c-fos
Myocardin6SAP domain familyDoes not bind directly to DNA, but binds to SRF as co-factorHeartSM 22, ANF
GATA-4, 5, 67GATA familyA/TGATAA/gMyocardium, endodermα-MHC, cardiac TnC, TnIc
Nkx-2.5 8 HomeoboxTNNAGTG (high affinity) C(A/T)TTAATTN (low affinity)Cardiac mesodermMLC2v, ANF, cardiac α-actin
HIF-19bHLHα/β heterodimers bind CANNTGUbiquitous; HIF-1β constitutively expressed, changes in levels of active HIF-1α induced by hypoxiaMLC2v, ANF, cardiac α-actin