靶點(diǎn) |
GST fusion protein with sequence HGHLHDSAEERRLIAEGDASPG EDRTPPGLAAEPERP, corresponding to amino acid residues 119-155 of human HCN4 (Accession Q9Y3Q4) , (MW: 31 kDa.).????Intracellular, N-terminus.
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總結(jié) |
Hyperpolarization-activated cation currents (Ih) appear in the heart and the brain and have a crucial role in controlling electrical pacemaker activity, contributing to biological processes such as heartbeat, sleep-wake cycle and synaptic plasticity.1,2The Ihcurrents are generated by the Hyperpolarization-activated cyclic nucleotide-gated channel family (HCN), which is comprised of four homologous members,HCN1-4.EachHCNsubunit consists of six transmembrane domains (TM), a pore region between TM5-TM6 and a binding domain for cyclic nucleotides (CNBD) in the cytoplasmic C-terminus.2TheHCNsubunits can form functional homomers and can also co-assemble into functional heteromers.2The channels are closely related to each other and share a homology of about 60%. However, their similarity decreases in the cytoplasmic N- and C-termini. TheHCN1-4 channels mainly differ from each other in their speed of activation and the extent to which they are modulated by cAMP.HCN1, weakly affected by cAMP, is the fastest channel, followed byHCN2,HCN3 andHCN4.HCN4 is highly expressed in a restricted manner in adult sinoatrial (SA) node, constituting a goodmolecular marker for the adult cardiac pacemaker and might serve as a unique marker of the developing SA node .4,5mRNA expression of HCN4is most abundant in medial habenula and anterior and principal relay nuclei of the thalamus.6
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