The mouse Tlr4 gene is the house mouse gene encoding Toll-like receptor 4. NCBI identifies it as Tlr4, GeneID21898. The DNA locus, its RNA transcripts and its receptor protein are distinct objects: measuring a sequence change does not directly measure receptor abundance or signalling output.[ref]
A1998 study linked two inherited defects in lipopolysaccharide responsiveness to the mouse Tlr4 gene. In
C3H/HeJ mice, the coding change was predicted to replace proline by histidine at receptor position712. C57BL/10ScCr mice carried a mutation eliminating normal receptor function. These animals were relatively resistant to endotoxin while being unusually susceptible to Gram-negative infection.[ref]The result motivates a distinction between avoiding an inflammatory response and recognizing an invading bacterium. A lower response to an isolated bacterial component can coexist with impaired defence against infection. It also illustrates the evidence needed to connect genotype and mechanism: association of a mutation with a phenotype, prediction of its protein consequence and measurement of cellular signalling are related steps, rather than interchangeable assays. The1998 host-genetic findings supported a role for Toll-like receptor 4 in lipopolysaccharide recognition and signalling; a coding variant alone is not a direct ligand-binding measurement.
New to topics? Read the docs here!