TABLE 1

Residues in h5-HT3A selected for cysteine substitution and their equivalents in other Cys-loop receptor subunits previously studied by fluorescence

Human h5-HT3APreviously Studied Positions in Cys-Loop Receptors as Potential VCF ReportersRegion
Human ρ1 GABAARat α1 GABAAHuman α1 GlyR
Asp74aSer66bN.T.Ala52cLoop 2
Tyr89N.T.N.T.Gln67cLoop D
Gln146Leu166bLeu127dLeu127cLoop E
Val196aAsp214eN.T.N.T.Loop F
Phe221N.T.N.T.N.T.Loop C
Met223Tyr241bN.T.His201cLoop C
Ser225aN.T.N.T.Asn203cLoop C
Ile238aN.T.N.T.N.T.Pre-M1
Arg239aN.T.N.T.Glu217cPre-M1
Arg241aN.T.N.T.Gln219cPre-M1
Leu243aN.T.N.T.Gly221cPre-M1
Val246aN.T.N.T.Leu224cPre-M1
Val247aN.T.N.T.Ile225cPre-M1
Leu249aN.T.N.T.Met227cPre-M1
  • N.T.; not tested in the listed subunit.

  • a Indicates that the position did not report fluorescence changes when mutated to Cys and labeled with a fluorophore in the indicated study. Residue numbering according to original publications and may differ from canonical sequence numbering. Other studies concerning studies of Cys-loop receptors by fluorescence labeling at other positions thank those in the present study include Mourot et al. (2008), Menny et al. (2017), and Polovinkin et al. (2018).

  • b Chang and Weiss (2002).

  • c Pless and Lynch (2009a).

  • d Muroi et al. (2006).

  • e Zhang et al. (2009).