AML1/Runx1 Is Important for the Development of Hindbrain Cholinergic Branchiovisceral Motor Neurons and Selected Cranial Sensory Neurons

• Published in: Proceedings of the National Academy of Sciences - PNAS 2004-07, Vol.101 (28), p.10343-10348
• Main Authors: Theriault, Francesca M., Roy, Priscillia, Stifani, Stefano, Jessell, Thomas M.
• Format: Article
• Language: English
• Subjects: Animals; Biological Sciences; Biology; Brain; Cholinergic Fibers - physiology; Cholinergics; Core Binding Factor Alpha 2 Subunit; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Embryos; Female; Ganglia; Gene Expression Regulation, Developmental; Hindbrain; Male; Mice; Motor ability; Motor neurons; Motor Neurons - physiology; Neurons; Neurons, Afferent - physiology; Pregnancy; Proto-Oncogene Proteins - genetics; Proto-Oncogene Proteins - metabolism; Quadrants; Rhombencephalon - cytology; Rhombencephalon - embryology; Rhombencephalon - physiology; Sensory neurons; Spinal cord; Transcription Factors - genetics; Transcription Factors - metabolism; Trigeminal ganglion; Trigeminal Ganglion - cytology; Trigeminal Ganglion - embryology; Trigeminal Ganglion - physiology; Vestibulocochlear Nerve - cytology; Vestibulocochlear Nerve - embryology; Vestibulocochlear Nerve - physiology
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0400768101

The mechanisms that regulate the acquisition of distinctive neuronal traits in the developing nervous system are poorly defined. It is shown here that the mammalian runt-related gene Runx1 is expressed in selected populations of postmitotic neurons of the embryonic central and peripheral nervous systems. These include cholinergic branchial and visceral motor neurons in the hindbrain, restricted populations of somatic motor neurons of the median and lateral motor columns in the spinal cord, as well as nociceptive and mechanoreceptor neurons in trigeminal and vestibulocochlear ganglia. In mouse embryos lacking Runx1 activity, hindbrain branchiovisceral motor neuron precursors of the cholinergic lineage are correctly specified but then fail to progress to a more differentiated state and undergo increased cell death, resulting in a neuronal loss in the mantle layer. In contrast, the development of cholinergic somatic motor neurons is unaffected. Runx1 inactivation also leads to a loss of selected sensory neurons in trigeminal and vestibulocochlear ganglia. These findings uncover previously unrecognized roles for Runx1 in the regulation of mammalian neuronal subtype development.