Journal article

Constitutive and Conditional Mutant Mouse Models for Understanding Dopaminergic Regulation of Orofacial Movements: Emerging Insights and Challenges

Katsunori Tomiyama, John Drago, John L Waddington, Noriaki Koshikawa



Among numerous mechanisms implicated in the regulation of orofacial movements, dopamine-containing neurons have received the most extensive study. Here we review the effects of a) constitutive knockout of D(1-5) dopamine receptors and b) conditional mutations with progressive ablation of D(1) receptor-expressing cells, on the topography of spontaneous and D(1)-like agonist-induced orofacial movements. In constitutive knockouts, D(1) and D(2) exert primary roles in regulating horizontal and vertical jaw movements, respectively, in opposite directions; in contrast, both D(1) and D(2) receptors regulate tongue protrusions and incisor chattering, in the same direction. D(3) and D(5) receptors pl..

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University of Melbourne Researchers


Awarded by Science Foundation Ireland

Funding Acknowledgements

The authors' studies would be impossible without the generous collaboration of our colleagues in molecular biology who have kindly made their mutants available to us; we are indebted to Emiliana Borrelli, Michelle Ehrlich, Sara Fuchs, David Grandy, Malcolm Low, Marcelo Rubinstein, Gunter Schutz, and David Sibley. These studies are supported by a grant for promotion of multidisciplinary research projects entitled Translational Research Network on Orofacial Neurological Disorders from the Ministry of Education, Culture, Sports, Science, and Technology of Japan (KT, NK) and a Nihon University Multidisciplinary Grant (KT, NK), Science Foundation Ireland Principal Investigator Grant 07/IN.1/B960 (JLW), and an Australian National Health and Medical Research Council Research Fellowship (JD).