TY - JOUR TI - Gene expression analysis reveals that formation of the mouse anterior secondary palate involves recruitment of cells from the posterior side AU - Li, Qun AU - Ding, Jixiang T2 - The International Journal of Developmental Biology AB - Cleft palate is a common birth defect caused by disruptions in secondary palate development. Anterior-posterior (A-P) regional specification plays a critical role in palate development and fusion. Previous studies have shown that at the molecular level, the anterior palate can be defined by the expression of Shox-2 and the posterior palate by Meox-2 expression in certain mouse strains. Here, we have extended previous studies by performing a more detailed analysis of these genes during mouse palate development. We found that the expression patterns of Shox-2 and Meox-2 are dynamic during palate development. At embryonic day 12.5 (E12.5), Shox-2 expression is localized to the anterior end and its expression domain covers less than 25% of the length of the palate shelf. The Shox-2 expression domain then gradually expands towards the posterior end and ultimately occupies more than 60% of the palate shelf by E14.5. The expansion of the Shox-2 domain may involve induction of Shox2 expression in additional cells. Reciprocally, the Meox-2 expression domain at E12.5 covers a large portion of the palate shelf, a region more than 70% of the entire palate, but then regresses to the posterior 25% by E14.5. This regression is likely caused by the repression of Meox-2 expression in certain Meox2 expressing cells, rather than the cessation of cell proliferation. Therefore, certain Meox-2 positive "primitive posterior cells" are differentiated/converted into Shox-2 positive "definitive anterior cells" during A-P regional specification. PY - 2007 DO - 10.1387/ijdb.062212ql VL - 51 IS - 2 SP - 167 EP - 172 J2 - Int. J. Dev. Biol. LA - en SN - 0214-6282 SN - 1696-3547 UR - https://ijdb.ehu.eus/article/062212ql Y2 - 2024/12/22/03:22:39 ER -