Molecular profiles of mitogen activated protein kinase signaling pathways in orofacial development.
BACKGROUND
Formation of the mammalian orofacial region involves multiple signaling pathways regulating sequential expression of and interaction between molecular signals during embryogenesis. The present study examined the expression patterns of members of the MAPK family in developing murine orofacial tissue.


METHODS
Total RNA was extracted from developing embryonic orofacial tissue during gestational days (GDs) 12-14 and used to prepare biotinylated cDNA probes, which were then denatured and hybridized to murine MAPK signaling pathways gene arrays.


RESULTS
Expression of a number of genes involved in the (ERK1/2) cascade transiently increased in the embryonic orofacial tissue over the developmental period examined. Numerous members of the SAPK/JNK cascade were constitutively expressed in the tissue. Genes known to play a role in p38 MAPK signaling exhibited constitutive expression during orofacial development. Western blot analysis demonstrated that ERK2/1, p38, and SAPK/JNK kinases are present in embryonic orofacial tissue on each of GD 12, 13, and 14. By using phospho-specific antibodies, active ERK was shown to be temporally regulated during orofacial development. Minimal amounts of active p38 and active SAPK/JNK were detected in orofacial tissue during GDs 12-14.


CONCLUSIONS
Our study documents specific expression patterns of genes coding for proteins belonging to the ERK1/2, p38, and SAPK/JNK MAPK families in embryonic orofacial tissue. We also demonstrate that active, phosphorylated forms of ERK1/2 only were detected in the embryonic tissue investigated, suggesting a more central role for members of this family in embryonic orofacial development.
Singh
Saurabh
S
Department of Molecular, Cellular and Craniofacial Biology, University of Louisville Birth Defects Center, ULSD, Louisville, Kentucky 40292, USA.
Yin
Xiaolong
X
Pisano
M Michele
MM
Greene
Robert M
RM
D000818:Animals; D045163:Antibodies, Phospho-Specific / Q000276:immunology / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D015151:Immunoblotting; D020935:MAP Kinase Signaling System; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D048052:Mitogen-Activated Protein Kinase 3 / Q000235:genetics / Q000378:metabolism; D048055:Mitogen-Activated Protein Kinase 8 / Q000235:genetics / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D009055:Mouth / Q000196:embryology* / Q000201:enzymology*; D011247:Pregnancy; D048051:p38 Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism
D045163:Antibodies, Phospho-Specific; D048052:Mitogen-Activated Protein Kinase 3; D048055:Mitogen-Activated Protein Kinase 8; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases