Shox2 is required for the proper development of the facial motor nucleus and the establishment of the facial nerves

BMC Neuroscience

John Cobb²  Deborah M Kurrasch¹  Jessica M Rosin² 

[1] Department of Medical Genetics, Alberta Children’s Hospital Research Institute, University of Calgary, 3330 Hospital Drive N.W., Room HS2275, Calgary T2N 4N1, AB, Canada;Department of Biological Sciences, University of Calgary, 2500 University Drive N.W., BI286D, Calgary T2N 1N4, AB, Canada

关键词: Facial (VII) nerves;    Facial motor nucleus;    Visceral motor neurons (vMNs);    Sonic hedgehog (Shh);    Islet 1 (Isl1);    Short stature homeobox 2 (Shox2) gene;   

Others  :  1228621
DOI  :  10.1186/s12868-015-0176-0

 received in 2015-03-09, accepted in 2015-06-12,  发布年份 2015

【 摘 要 】

Background

Axons from the visceral motor neurons (vMNs) project from nuclei in the hindbrain to innervate autonomic ganglia and branchial arch-derived muscles. Although much is known about the events that govern specification of somatic motor neurons, the genetic pathways responsible for the development of vMNs are less well characterized. We know that vMNs, like all motor neurons, depend on sonic hedgehog signaling for their generation. Similarly, the paired-like homeobox 2b (Phox2b) gene, which is expressed in both proliferating progenitors and post-mitotic motor neurons, is essential for the development of vMNs. Given that our previous study identified a novel role for the short stature homeobox 2 (Shox2) gene in the hindbrain, and since SHOX2 has been shown to regulate transcription of islet 1 (Isl1), an important regulator of vMN development, we sought to determine whether Shox2 is required for the proper development of the facial motor nucleus.

Results

Using a Nestin-Cre driver, we show that elimination of Shox2 throughout the brain results in elevated cell death in the facial motor nucleus at embryonic day 12.5 (E12.5) and E14.5, which correlates with impaired axonal projection properties of vMNs. We also observed changes in the spatial expression of the vMN cell fate factors Isl1 and Phox2b, and concomitant defects in Shh and Ptch1 expression in Shox2 mutants. Furthermore, we demonstrate that elimination of Shox2 results in the loss of dorsomedial and ventromedial subnuclei by postnatal day 0 (P0), which may explain the changes in physical activity and impaired feeding/nursing behavior in Shox2 mutants.

Conclusions

Combined, our data show that Shox2 is required for development of the facial motor nucleus and its associated facial (VII) nerves, and serves as a new molecular tool to probe the genetic programs of this understudied hindbrain region.

【 授权许可】

   
2015 Rosin et al.

【 图 表 】

Figure1.

Figure2.

Figure3.

Figure4.

Figure5.

Figure6.

Figure7.

【 参考文献 】

• [1]Lumsden A, Keynes R: Segmental patterns of neuronal development in the chick hindbrain. Nature 1989, 337:424-428.
• [2]Herrup K, Diglio TJ, Letsou A: Cell lineage relationships in the development of the mammalian CNS. I. The facial nerve nucleus. Dev Biol 1984, 103:329-336.
• [3]Gavalas A, Ruhrberg C, Livet J, Henderson CE, Krumlauf R: Neuronal defects in the hindbrain of Hoxa1, Hoxb1 and Hoxb2 mutants reflect regulatory interactions among these Hox genes. Development 2003, 130:5663-5679.
• [4]Gaunt SJ, Krumlauf R, Duboule D: Mouse homeo-genes within a subfamily, Hox-1.4, -2.6 and -5.1, display similar anteroposterior domains of expression in the embryo, but show stage- and tissue-dependent differences in their regulation. Development 1989, 107:131-141.
• [5]Dolle P, Lufkin T, Krumlauf R, Mark M, Duboule D, Chambon P: Local alterations of Krox-20 and Hox gene expression in the hindbrain suggest lack of rhombomeres 4 and 5 in homozygote null Hoxa-1 (Hox-1.6) mutant embryos. Proc Natl Acad Sci USA 1993, 90:7666-7670.
• [6]Studer M, Lumsden A, Ariza-McNaughton L, Bradley A, Krumlauf R: Altered segmental identity and abnormal migration of motor neurons in mice lacking Hoxb-1. Nature 1996, 384:630-634.
• [7]Pattyn A, Vallstedt A, Dias JM, Sander M, Ericson J: Complementary roles for Nkx6 and Nkx2 class proteins in the establishment of motoneuron identity in the hindbrain. Development 2003, 130:4149-4159.
• [8]Tsuchida T, Ensini M, Morton SB, Baldassare M, Edlund T, Jessell TM, et al.: Topographic organization of embryonic motor neurons defined by expression of LIM homeobox genes. Cell 1994, 79:957-970.
• [9]Auclair F, Valdes N, Marchand R: Rhombomere-specific origin of branchial and visceral motoneurons of the facial nerve in the rat embryo. J Comp Neurol 1996, 369:451-461.
• [10]Garel S, Garcia-Dominguez M, Charnay P: Control of the migratory pathway of facial branchiomotor neurones. Development 2000, 127:5297-5307.
• [11]Traiffort E, Charytoniuk D, Watroba L, Faure H, Sales N, Ruat M: Discrete localizations of hedgehog signalling components in the developing and adult rat nervous system. Eur J Neurosci 1999, 11:3199-3214.
• [12]Jessell TM: Neuronal specification in the spinal cord: inductive signals and transcriptional codes. Nat Rev Genet 2000, 1:20-29.
• [13]Briscoe J, Chen Y, Jessell TM, Struhl G: A hedgehog-insensitive form of patched provides evidence for direct long-range morphogen activity of sonic hedgehog in the neural tube. Mol Cell 2001, 7:1279-1291.
• [14]Briscoe J, Pierani A, Jessell TM, Ericson J: A homeodomain protein code specifies progenitor cell identity and neuronal fate in the ventral neural tube. Cell 2000, 101:435-445.
• [15]Ericson J, Morton S, Kawakami A, Roelink H, Jessell TM: Two critical periods of Sonic Hedgehog signaling required for the specification of motor neuron identity. Cell 1996, 87:661-673.
• [16]Akazawa C, Kohsaka S: In vivo characterization of sonic hedgehog in the peripheral nerve regeneration. Brain Nerve 2007, 59:1341-1346.
• [17]Dubreuil V, Hirsch MR, Pattyn A, Brunet JF, Goridis C: The Phox2b transcription factor coordinately regulates neuronal cell cycle exit and identity. Development 2000, 127:5191-5201.
• [18]Pattyn A, Hirsch M, Goridis C, Brunet JF: Control of hindbrain motor neuron differentiation by the homeobox gene Phox2b. Development 2000, 127:1349-1358.
• [19]Pfaff SL, Mendelsohn M, Stewart CL, Edlund T, Jessell TM: Requirement for LIM homeobox gene Isl1 in motor neuron generation reveals a motor neuron-dependent step in interneuron differentiation. Cell 1996, 84:309-320.
• [20]Thor S, Ericson J, Brannstrom T, Edlund T: The homeodomain LIM protein Isl-1 is expressed in subsets of neurons and endocrine cells in the adult rat. Neuron 1991, 7:881-889.
• [21]Sun Y, Dykes IM, Liang X, Eng SR, Evans SM, Turner EE: A central role for Islet1 in sensory neuron development linking sensory and spinal gene regulatory programs. Nat Neurosci 2008, 11:1283-1293.
• [22]Liang X, Song MR, Xu Z, Lanuza GM, Liu Y, Zhuang T, et al.: Isl1 is required for multiple aspects of motor neuron development. Mol Cell Neurosci 2011, 47:215-222.
• [23]Ashwell KW: The adult mouse facial nerve nucleus: morphology and musculotopic organization. J Anat 1982, 135:531-538.
• [24]Ashwell KW, Watson CR: The development of facial motoneurones in the mouse—neuronal death and the innervation of the facial muscles. J Embryol Exp Morphol 1983, 77:117-141.
• [25]Cobb J, Dierich A, Huss-Garcia Y, Duboule D: A mouse model for human short-stature syndromes identifies Shox2 as an upstream regulator of Runx2 during long-bone development. Proc Natl Acad Sci USA 2006, 103:4511-4515.
• [26]Vickerman L, Neufeld S, Cobb J: Shox2 function couples neural, muscular and skeletal development in the proximal forelimb. Dev Biol 2011, 350:323-336.
• [27]Bobick BE, Cobb J: Shox2 regulates progression through chondrogenesis in the mouse proximal limb. J Cell Sci 2012, 125:6071-6083.
• [28]Yu L, Gu S, Alappat S, Song Y, Yan M, Zhang X, et al.: Shox2-deficient mice exhibit a rare type of incomplete clefting of the secondary palate. Development 2005, 132:4397-4406.
• [29]Gu S, Wei N, Yu L, Fei J, Chen Y: Shox2-deficiency leads to dysplasia and ankylosis of the temporomandibular joint in mice. Mech Dev 2008, 125:729-742.
• [30]Blaschke RJ, Hahurij ND, Kuijper S, Just S, Wisse LJ, Deissler K, et al.: Targeted mutation reveals essential functions of the homeodomain transcription factor Shox2 in sinoatrial and pacemaking development. Circulation 2007, 115:1830-1838.
• [31]Espinoza-Lewis RA, Yu L, He F, Liu H, Tang R, Shi J, et al.: Shox2 is essential for the differentiation of cardiac pacemaker cells by repressing Nk2-5. Dev Biol 2009, 327:376-385.
• [32]Scott A, Hasegawa H, Sakurai K, Yaron A, Cobb J, Wang F: Transcription factor short stature homeobox 2 is required for proper development of tropomyosin-related kinase B-expressing mechanosensory neurons. J Neurosci 2011, 31:6741-6749.
• [33]Rosin JM, McAllister BB, Dyck RH, Percival CJ, Kurrasch DM, Cobb J: Mice lacking the transcription factor SHOX2 display impaired cerebellar development and deficits in motor coordination. Dev Biol 2015, 399:54-67.
• [34]Hoffmann S, Berger IM, Glaser A, Bacon C, Li L, Gretz N, et al.: Islet1 is a direct transcriptional target of the homeodomain transcription factor Shox2 and rescues the Shox2-mediated bradycardia. Basic Res Cardiol 2013, 108:339.
• [35]Tronche F, Kellendonk C, Kretz O, Gass P, Anlag K, Orban PC, et al.: Disruption of the glucocorticoid receptor gene in the nervous system results in reduced anxiety. Nat Genet 1999, 23:99-103.
• [36]Tvrdik P, Capecchi MR: Reversal of Hox1 gene subfunctionalization in the mouse. Dev Cell 2006, 11:239-250.
• [37]Rosin JM, Abassah-Oppong S, Cobb J: Comparative transgenic analysis of enhancers from the human SHOX and mouse Shox2 genomic regions. Hum Mol Genet 2013, 22:3063-3076.
• [38]Dykes IM, Tempest L, Lee SI, Turner EE: Brn3a and Islet1 act epistatically to regulate the gene expression program of sensory differentiation. J Neurosci 2011, 31:9789-9799.
• [39]Geisen MJ, Di Meglio T, Pasqualetti M, Ducret S, Brunet JF, Chedotal A, et al.: Hox paralog group 2 genes control the migration of mouse pontine neurons through slit-robo signaling. PLoS Biol 2008, 6:e142.
• [40]Goddard JM, Rossel M, Manley NR, Capecchi MR: Mice with targeted disruption of Hoxb-1 fail to form the motor nucleus of the VIIth nerve. Development 1996, 122:3217-3228.
• [41]Susulic VS, Frederich RC, Lawitts J, Tozzo E, Kahn BB, Harper ME, et al.: Targeted disruption of the beta 3-adrenergic receptor gene. J Biol Chem 1995, 270:29483-29492.
• [42]Brinster RL, Braun RE, Lo D, Avarbock MR, Oram F, Palmiter RD: Targeted correction of a major histocompatibility class II E alpha gene by DNA microinjected into mouse eggs. Proc Natl Acad Sci USA 1989, 86:7087-7091.
• [43]Nagy A, Gertsenstein M, Vintersten K, Behringer RR: Manipulating the mouse embryo: a laboratory manual. 3rd edition. Cold Spring Harbor Press, New York; 2003.
• [44]Cobb J, Duboule D: Comparative analysis of genes downstream of the Hoxd cluster in developing digits and external genitalia. Development 2005, 132:3055-3067.
• [45]Echelard Y, Epstein DJ, St-Jacques B, Shen L, Mohler J, McMahon JA, et al.: Sonic hedgehog, a member of a family of putative signaling molecules, is implicated in the regulation of CNS polarity. Cell 1993, 75:1417-1430.
• [46]Dodd J, Morton SB, Karagogeos D, Yamamoto M, Jessell TM: Spatial regulation of axonal glycoprotein expression on subsets of embryonic spinal neurons. Neuron 1988, 1:105-116.