Functional analysis of mSix1-8 in mouse.

<p>(A) Mutation analysis of mSix1-8 in mouse. Wild-type (mSix1-8wt-LacZ, Aa) and mutated [(mSix1-8NR1-4m-LacZ, Ab) and (mSix1-8TCF/LEFm2-LacZ, Ac)] transgenes were used for transgenesis and ß-Gal localization was examined at E10.5. Embryos injected with the wild-type transgene showed ß-Gal activity specifically in the trigeminal ganglion, the VII/VIII ganglion complex and epibranchial placode/ganglia (Aa)[<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0136666#pone.0136666.ref017" target="_blank">17</a>]. However, ß-Gal activity was almost completely lost in an embryo carrying NR1-4m mutation, with the exception of a small number of ectopic ß-Gal-positive cells in the cervical area (Ab). In an embryo carrying TCF/LEFm2 mutation, ß-Gal activity was lost in the sensory organs and ganglia, with the exception of ectopic activity in the somites (Ac). drg: dorsal root ganglia, so: somites, V: trigeminal ganglion, VII/VIII: VII/VIII ganglion complex, IX: petrosal ganglion, X: nodose ganglion. Scale bars: 1 mm. (B) Summary of the phenotypes of transgenic mouse embryos. transgenic embryos: the total number of transgenic embryos obtained using each transgene, pattern A: number of embryos with ß-Gal staining pattern in which the signal in the trigeminal ganglion stands out as the major ß-Gal-positive domain (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0136666#pone.0136666.g003" target="_blank">Fig 3Aa</a> represents a typical pattern A staining), pattern B: number of embryos with ß-Gal staining in which signals in the cranial ganglia was reduced while those in the DRG were relatively unaffected, embryos with ectopic expression: number of embryos with an ectopic LacZ staining, embryos without sensory ganglia-expression: number of embryos without a LacZ staining in the sensory ganglia. Parts of the results obtained using the wild-type transgene were reported previously [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0136666#pone.0136666.ref017" target="_blank">17</a>].