Comparison of the expression patterns of two LIM-homeodomain genes, Lhx6 and L3/Lhx8, in the developing palate

Structured Abstract Authors– Zhang Y, Mori T, Takaki H, Takeuchi M, Iseki K, Hagino S, Murakawa M, Yokoya S, Wanaka A. Objectives– To compare and contrast the gene expression of two LIM-homeobox type transcription factors, Lhx6 and L3/Lhx8, in secondary palate formation. Methods– In situ hybridization histochemistry with digoxygenin (DIG) labelled cRNA probes specific for Lhx6 and L3/Lhx8. Materials– Serial cryo-sections of embryonic day (E)13.5, 14.5, and 15.5 mice (C57BL/6). Outcome Measure– Comparison of the signal intensities of NBT/BCIP precipitate by alkaline phosphatase conjugated anti-DIG antibody. Results– From E13.5 to E15.5, Lhx6 and L3/Lhx8 signals are detected in palatal mesenchyme, but the L3/Lhx8 signal is much more intense than the Lhx6 signal. In palatal epithelium, covering the mesenchyme, Lhx6 mRNA is transiently expressed at E14.5, while L3/Lhx8 mRNA expression is never detected throughout the development. Conclusion– Lhx6 and L3/Lhx8 functions may be partially redundant in the mesenchyme of the secondary palate, but not in the palatal epithelium.