title: PIP2 and PIP3 interact with N-terminus region of TRPM4 channel.
abstract: The transient receptor potential melastatin 4 (TRPM4) is a calcium-activated non-selective ion channel broadly expressed in a variety of tissues. Receptor has been identified as a crucial modulator of numerous calcium dependent mechanisms in the cell such as immune response, cardiac conduction, neurotransmission and insulin secretion. It is known that phosphoinositide lipids (PIPs) play a unique role in the regulation of TRP channel function. However the molecular mechanism of this process is still unknown. We characterized the binding site of PIP2 and its structural analogue PIP3 in the E733-W772 proximal region of the TRPM4 N-terminus via biophysical and molecular modeling methods. The specific positions R755 and R767 in this domain were identified as being important for interactions with PIP2/PIP3 ligands. Their mutations caused a partial loss of PIP2/PIP3 binding specificity. The interaction of PIP3 with TRPM4 channels has never been described before. These findings provide new insight into the ligand binding domains of the TRPM4 channel.
authors.affiliation: 2nd Faculty of Medicine, Charles University in Prague, 15006 Prague, Czech Republic; Institute of Physiology, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic.
authors.forename: Kristyna
authors.initials: K
authors.lastname: Bousova
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic; Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic.
authors.forename: Michaela
authors.initials: M
authors.lastname: Jirku
authors.affiliation: Institute of Microbiology, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic.
authors.forename: Ladislav
authors.initials: L
authors.lastname: Bumba
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Bednarova
authors.affiliation: Institute of Microbiology, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Sulc
authors.affiliation: 3rd Faculty of Medicine, Charles University in Prague, 10000 Prague, Czech Republic.
authors.forename: Miloslav
authors.initials: M
authors.lastname: Franek
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic.
authors.forename: Ladislav
authors.initials: L
authors.lastname: Vyklicky
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic.
authors.forename: Jiri
authors.initials: J
authors.lastname: Vondrasek
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic. Electronic address: jan.teisinger@fgu.cas.cz.
authors.forename: Jan
authors.initials: J
authors.lastname: Teisinger
mesh_terms: D000595:Amino Acid Sequence; D004134:Dimyristoylphosphatidylcholine / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D062105:Molecular Docking Simulation; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000378:metabolism*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D050053:TRPM Cation Channels / Q000737:chemistry* / Q000378:metabolism*
chemical_list: C108836:1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine; D010446:Peptide Fragments; D019269:Phosphatidylinositol 4,5-Diphosphate; D050053:TRPM Cation Channels; C437888:TRPM4 protein, human; D004134:Dimyristoylphosphatidylcholine
keywords: Binding site; Circular dichroism; Molecular modeling; PIP2; Surface plasmon resonance; TRPM4 channel