Expression of Msx1 and Dlx1 during Dumbo rat head development: correlation with morphological features

Abstract

The Dumbo rat possesses some characteristics that evoke several human syndromes, such as Treacher-Collins: shortness of the maxillary, zygomatic and mandibular bones, and low position of the ears. Knowing that many homeobox genes are candidates in craniofacial development, we investigated the involvement of the Msx1 and Dlx1 genes in the Dumbo phenotype with the aim of understanding their possible role in abnormal craniofacial morphogenesis and examining the possibility of using Dumbo rat as an experimental model for understanding abnormal craniofacial development. We studied the expression of these genes during craniofacial morphogenesis by RT-PCR method. We used Dumbo embryos at E12 and E14 and included the Wistar strain as a control. Semi-quantitative PCR analysis demonstrated that Msx1 and Dlx1 are expressed differently between Dumbo and Wistar rats, indicating that their low expression may underly the Dumbo phenotype.

Deletion of a conserved regulatory element required for Hmx1 expression in craniofacial mesenchyme in the dumbo rat: a novel cause of congenital ear malformation

“…Prior to the mapping of the rat dmbo mutation to the Hmx1 locus, dysregulation of the homeobox genes Msx1 and Dlx1 was proposed as a causative mechanism for the rat dumbo phenotype ( Katerji et al, 2009 ). Loss-of-function mutations in Msx1/2 and Dlx1/2 result in much more extensive defects in craniofacial development than the phenotypes observed in the dumbo rat and mouse ( Ishii et al, 2005 ; Qiu et al, 1997 ; Qiu et al, 1995 ).…”

Reconstruction of drug-induced cleft palate using bone marrow mesenchymal stem cell in rodents

“…Adhesion and fusion of the shelves take place by the transformation of medial edge epithelial (MEE) cells and apoptosis of MEE. The fusion of the shelves is initiated in the third palatal Rugae region and extends anteriorly, and posteriorly[ 22 23 ] growth factor β3 is specifically required for the adhesion and fusion of the palatal shelves. The phenotypical analysis shows that delayed closure of the secondary palate at the anterior end leading to a failed fusion of primary and secondary palates.…”