Research Report 2010 - MDC

Dr. Katja Grossmann*Dr. Elena RoccaDr. Elvira Rohde (guest)Dr. Robert StormDr. Hagen WendeDr. Elena VasyutinaGraduate andUndergraduate StudentsFabian Ahrens*Kira BaluevaJustyna Cholewa-WaclawMaciej Czajkowski*Pedro Garcia Vallecillo*Shiqi JiaUlrich Koestner*Diana LenhardRobin SchneiderJochen WelckerTechniciansBettina BarbyMaria Braunschweig*Sven BuchertKarin GottschlingCarola GriffelAndrea LeschkeIvonne SchiffnerAnimal CaretakersClaudia PäselerPetra StallerowSecretariatDr. Timkehet Teffera**part of the period reportedFigure 1. Insm1 expression in the developing embryo. To analyzeInsm1 expression, we took advantage of the Insm1lacZallele in which lacZ sequences replace the Insm1-codingsequence. Insm1lacZ/+ mice. LacZ expression is detected in theentire primary sympathetic ganglion chain (arrowhead), aswell as in sensory ganglia and in the central nervous system.In a collaborative effort, we could also show that Insm1controls the differentiation of monoaminergic neuronsin the hindbrain. These neurons use either the neurotransmitterserotonin or noradrenaline, both of whichhave a wide range of complementary actions and areimplicated in the pathophysiology of many commonneurological and psychiatric disorders. In Insm1 mutantmice, serotonergic precursors located in the ventralhindbrain, began to differentiate despite the reducedexpression of the postmitotic serotonergic fatedeterminants (Pet1, Lmx1 and Gata2), but failed toproduce serotonin due to the lack of tryptophanhydroxylase 2, an enzyme essential for serotoninbiosynthesis. In brainstem noradrenergic centers ofInsm1 mutants, expression of tyrosine hydroxylase wasimpaired, resulting in aberrant noradrenergic differentiation.The bHLH factor Olig3 functions in thedetermination of neuronal fatesJustyna Cholewa-Waclaw, Robert Storm, DominiqueBröhl, Thomas Müller (in collboration with MathiasTreier, EMBL Heidelberg)The hindbrain is the part of the central nervous systemthat monitors and regulates inner organ function suchas the rate of heartbeat, blood pressure and breathing.To achieve this, hindbrain neurons receive and integrateviscerosensory information from inner organs. Thecomplex circuitry in which neurons participate is establishedduring development and depends on their spatiallyand temporally ordered appearance.One important class of genes that regulates cellulardiversity in the nervous system encodes basic helixloop-helix(bHLH) transcription factors. The Olig3 bHLHfactor is expressed in the ventricular zone of the dorsalFunction and Dysfunction of the Nervous System 151