Project description:The tongue is a muscular organ in the vertebrate oral cavity that performs complex functions in daily life, including feeding and phonetic articulation. The tongue consists of mesenchyme cells of two distinct origins: the muscle cells are derived from occipital somites whereas the tendons and other connective tissues derived from the cranial neural crest. Cranial neural crest cells are important for the initiation of tongue swelling and proper patterning of intrinsic and extrinsic tongue muscle groups. However, little is known regarding the molecular and cellular mechanisms of tongue morphogenesis. We show that the odd-skipped related 1 (Osr1) transcription factor exhibits dynamic expression in the tongue mesenchyme during early tongue development. Tissue-specific inactivation of Osr1 in the early neural crest cells resulted in ectopic cartilage formation in the mouse tongue. We show that Sox9, the master regulator of chondrocyte differentiation, is initially widely expressed in the neural crest derived mesenchyme in the tongue and subsequently down-regulated concomitant by up-regulation of Osr1 expression. Osr1 mutant embryos exhibit persistent expression of Sox9 and chondrocyte differentiation from the neural crest derived tongue mesenchyme. Further biochemical analyses indicate that Osr1 may directly suppresses Sox9 gene expression in the tongue mesenchyme. These data reveal a novel mechanism in suppression of chondrogenic fate during tongue development. Remarkably, the ectopic cartilage in the Osr1 mutant mice resembles the entoglossal cartilage naturally develops in the avian tongue. These results suggest that modulation of expression of Osr1 may underline the evolutionary divergence in tongue cartilage formation. RNAs were isolated from microdissected E12 embryonic mouse tongue of Osr1f/-;Wnt1cre and control littermates and characterized by RNAseq E12 mouse embryonic tongues were micro-dissceted, 3 pairs of control and mutant samples were pooled for the RNA extraction
Project description:The tongue is a muscular organ in the vertebrate oral cavity that performs complex functions in daily life, including feeding and phonetic articulation. The tongue consists of mesenchyme cells of two distinct origins: the muscle cells are derived from occipital somites whereas the tendons and other connective tissues derived from the cranial neural crest. Cranial neural crest cells are important for the initiation of tongue swelling and proper patterning of intrinsic and extrinsic tongue muscle groups. However, little is known regarding the molecular and cellular mechanisms of tongue morphogenesis. We show that the odd-skipped related 1 (Osr1) transcription factor exhibits dynamic expression in the tongue mesenchyme during early tongue development. Tissue-specific inactivation of Osr1 in the early neural crest cells resulted in ectopic cartilage formation in the mouse tongue. We show that Sox9, the master regulator of chondrocyte differentiation, is initially widely expressed in the neural crest derived mesenchyme in the tongue and subsequently down-regulated concomitant by up-regulation of Osr1 expression. Osr1 mutant embryos exhibit persistent expression of Sox9 and chondrocyte differentiation from the neural crest derived tongue mesenchyme. Further biochemical analyses indicate that Osr1 may directly suppresses Sox9 gene expression in the tongue mesenchyme. These data reveal a novel mechanism in suppression of chondrogenic fate during tongue development. Remarkably, the ectopic cartilage in the Osr1 mutant mice resembles the entoglossal cartilage naturally develops in the avian tongue. These results suggest that modulation of expression of Osr1 may underline the evolutionary divergence in tongue cartilage formation. RNAs were isolated from microdissected E12 embryonic mouse tongue of Osr1f/-;Wnt1cre and control littermates and characterized by RNAseq
Project description:RNAseq comparison of gene expression profiles in Hand2-Cre driven Msx1/Msx2 double conditional mutant and control mouse embryonic mandible
Project description:We investigated Smad4-mediated TGF-beta signaling in the development of occipital somite-derived myogenic progenitors during tongue morphogenesis by comparing the transcriptomes of tongue derived from Myf5-Cre;Smad4flox/flox mutant and Myf5-Cre;Smad4flox/+ control mice at day E13.5. Based on gene expression profiles and functional studies, we elucidated the influences Smad4 activity and TGF-beta signaling have on the gene expression profiles underlying tongue development. The data are consistent with the hypothesis that TGF-beta-Smad4-FGF6 signaling cascade plays a crucial role in myogenic cell fate determination and lineage progression during tongue myogenesis. We obtained RNA samples from tongue tissues of mutant and control mouse embryos (C57BL/6J) at day E13.5 RNA and subjected them to analysis on Affymetrix GeneChip Mouse Genome 430 2.0 Arrays.
Project description:We investigated Smad4-mediated TGF-beta signaling in the development of occipital somite-derived myogenic progenitors during tongue morphogenesis by comparing the transcriptomes of tongue derived from Myf5-Cre;Smad4flox/flox mutant and Myf5-Cre;Smad4flox/+ control mice at day E13.5. Based on gene expression profiles and functional studies, we elucidated the influences Smad4 activity and TGF-beta signaling have on the gene expression profiles underlying tongue development. The data are consistent with the hypothesis that TGF-beta-Smad4-FGF6 signaling cascade plays a crucial role in myogenic cell fate determination and lineage progression during tongue myogenesis.
Project description:Determine whether 4NQO treatment may modulate gene expression in mouse tongue. C57BL/6J mice were given 4NQO (100ug/ml in drink) for 8 weeks; Non-treated control samples were used for comparison.