Primary cilia regulate Shh activity in the control of molar tooth number.

ABSTRACT: Primary cilia mediate Hh signalling and mutations in their protein components affect Hh activity. We show that in mice mutant for a cilia intraflagellar transport (IFT) protein, IFT88/polaris, Shh activity is increased in the toothless diastema mesenchyme of the embryonic jaw primordia. This results in the formation of ectopic teeth in the diastema, mesial to the first molars. This phenotype is specific to loss of polaris activity in the mesenchyme since loss of Polaris in the epithelium has no detrimental affect on tooth development. To further confirm that upregulation of Shh activity is responsible for the ectopic tooth formation, we analysed mice mutant for Gas1, a Shh protein antagonist in diastema mesenchyme. Gas1 mutants also had ectopic diastema teeth and accompanying increased Shh

SUBMITTER: Ohazama A 

PROVIDER: S-EPMC2727556 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature