G Protein-coupled receptors

 Ion channels

 Nuclear receptors

 Protein kinases

 Cytokines and receptors

 Cell surface molecules and ligands

 Transporters

 Enzymes

   Oxidoreductases (EC1)

   Transferases (EC2)

     Methyltransferases [EC:2.1.1.-]

       COMT [HSA:1312] [KO:K00545]

       DNMT [HSA:1786 1788 1789] [KO:K00558 K17398 K17399]

       DNMT1 [HSA:1786] [KO:K00558]

       EZH [HSA:2145 2146] [KO:K17451 K11430]

       EZH2 [HSA:2146] [KO:K11430]

       TYMS [HSA:7298] [KO:K00560]

     Acyltransferases [EC:2.3.1.-]

     gamma-Glutamyltransferase [EC:2.3.2.2]

     E3 ubiquitin-protein ligase [EC:2.3.2.27]

     ATP citrate synthase [EC:2.3.3.8]

     Hexosyltransferases [EC:2.4.1.-]

     Pentosyltransferases [EC:2.4.2.-]

     Alkyl/Aryl transferases [EC:2.5.1.-]

     Aminotransferase [EC:2.6.1.-]

     Phosphotransferase [EC:2.7.1.-]

     DNA polymerase [EC:2.7.7.7]

     Reverse transcriptase [EC:2.7.7.49]

   Hydrolases (EC3)

   Lyases (EC4)

   Isomerases (EC5)

   Ligases (EC6)

 Nucleic acids

 Not elsewhere classified