Example sentences for: lgic
How can you use “lgic” in a sentence? Here are some example sentences to help you improve your vocabulary:
The first subunit of the 5-HT 3 R was cloned in 1991 [ 7 ] . The sequence of this subunit was shown to be highly homologous to LGIC receptors and thus identified the 5-HT 3 R receptor as another member of this superfamily [ 7 8 9 ] . Similar to other LGIC receptors, more than one subtype has been identified.
Mutagenesis studies have identified the interaction of amino acids W89 and R91 in the binding of 5-HT 3 R ligands [ 24 23 ] . Studies conducted in our laboratory have identified three additional putative binding site residues (Y140, Y142, and Y152) [ 25 ] . W89 and R91 are present in a conserved region of LGIC receptors often referred to as loop D [ 24 26 ] . Similarly, Y140, Y142 and Y152 are located in the region homologus to E loop region of nicotinic AchR.
This orientation of an amino group interacting with an aromatic amino acid in a cation-π interaction has been shown for the nicotinic acetylcholine receptor and has been hypothesized for many LGIC receptors [ 28 29 30 26 ] . This conclusion is based on both the magnitude of the change observed on the wild type receptor for removal of the amino group (400 fold) compared to the effect of the Y142A mutation on lerisetron binding (160 fold) and the lack of any major change in K i for analog 2 as a result of this mutation.
This structure is supported by site-directed mutagenesis data [ 25 ] as well as structural predictions obtained from other LGIC receptors [ 31 ] . The recent determination of the structure of a nicotinic acetylcholine binding protein [ 27 ] that shares significant homology with the LGIC family also supports a loop structure in this part of the protein.
The AChBP displays a large amount of homology to the amino terminal of LGIC receptors and thus may be similar in structure [ 20 24 ] . The crystal structure of this protein reveals a loose 3 residue turn incorporating the conserved glycine residue [ 24 ] . Homologous residues in other LGIC subunits have also been identified and are shown in Figure 1. The residues identified in this study as altering binding affinity of 5-HT 3 R ligands would also be present on the same surface if this structure is present in the 5-HT 3 R. While Y140 lies somewhat outside the region identified by Chiara in the nAChR (homologous to γN107), γL109 and γL119 are homologous to Y142 and Y152 of the 5-HT 3AS R. The ability of lerisetron to interact with both Y142 and Y152 also supports the hypothesis that these two amino acids are present in a loop structure since the eight intervening residues would position Y142 and Y152 too far apart to permit them both to interact with a single ligand even if they were interacting with functional groups on opposite ends of the molecule.
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