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Workshop on Neural Prepatterning and Specification Instituto Juan March de Estudios e Investigaciones CENTRO DE REUNIONES 126 INTERNACIONALES SOBRE BIOLOGÍA Workshop on N eural Prepatterning and Specification Organized by K. G. Sto rey and J. Modolell D. J. Anderson C. KHimht R. L. Cagan S. Martínez J. A. Campos-Ortega R. Mayor W. Chia J. Modolell A. Chitnis M. A. Nieto C. Damhly-Chaudiere N. Papalopulu C. Q. Doe A. Rui1 i Altaba A. Giangrande Y. Sasai A. Jarman P. Simpson ' M. Kessel C. D. Stern C. Kintncr K. G. Storey Instituto Juan March de Estudios e Investigaciones CENTRO DE REUNIONES 126 INTERNACIONALES SOBRE BIOLOGÍA Workshop on Neural Prepatterning and Specification Organized by K. G. Storey and J. Modolell D. J. Anderson C. KHimbt R. L. Cagan S. Martínez J. A. Campos-Ortega R. Mayor W. Chia J. Modolell A. Chitnis M. A. Nieto C. Dambly-Chaudiere N. Papalopulu C. Q. Doe ~, ~ ... e A. Ruiz i Altaba A. Giangrande ·[ -= ·- l~ , Y. Sasai A. Jarman ":r ~ P. Simpson ~ ... M. Kessel ' v¿ 1 v('~ , C. D. Stern ~ --_.,.. C. Kintner K. G. Storey Instituto Juan March (Madrid) The lectures summarized in this publication were presented by their authors at a workshop held on the 181h through the 2oth of June, 2001, at the Instituto Juan March. Depósito Legal: M-31612-2001 Impresión: Ediciones Peninsular. Tomelloso, 27. 28026 Madrid Instituto Juan March (Madrid) INDEX PAGE Jntroduction: K. G. Storey and J. Modolell.................................................... 7 Session 1: Neural prepatterning Chair: José A. Campos-Ortega .................................................................. 11 Juan Modolell: The iroquois genes in Drosophila and vertebrates.. .. ...... .. .. .. .. .. 13 Pat Simpson: A common prepattem for the sensory bristles on the scutum of higher flies .................... ... .. .. ..... ... .. .... ... .. .. .. ........ .. .. ... ... .. ... ... .. ... 16 Claudio D. Stern: Early steps ofneural induction. .. ...... .... .. .. .. .... ... .. ....... ... 18 Michael Kessel: The specification of prospective epidermal, neural crest and neural territories in early vertebrate embryos.... .. .... ...... ..................... .. .. .... 19 Short talk: José Luís Gómez-Skarmeta: The Wnt-activated Xiro-1 gene encodes a repressor that is essential for neural development and downregulates Bmp-4. 2 O Yoshiki Sasai: Molecular regulation of specification of Xenopus neuroectoderm and neural crest.. ............ .. ............ .... .. .. ........ ......... ..... ... .... ... .. .. .... 21 Ariel Ruiz i Altaba: The SHH-GLI pathway and the control of dorsal brain development and tumorigenesis. .... ... ........ ... .. .. .. .. .. .. ... .. .. .. .. ... .. ... .. 2 2 Salvador Martínez: Secondary organizers and brain patteming.. .. ... ... ... .. .... .. 23 Ross L. Cagan: Patteming the fly retina.. ...... ........ ..................... ... ........... 24 Short talks: Kristen Kroll: The role of gemmm in vertebrate neural cell fate determination. ... ... .. ... .. .... ... .. .. .. ... ... .. .... ..... .... ..... .. .. .. .. .. ... 25 Nobue Itasaki: Neural patteming along the antero-posterior axis in vertebrate embryos... ........................................... ............... ........ 2 6 Roberto Mayor: Patteming the neural crest in the ectoderm of X eno pus...... .. .... 2 7 M. Angela Nieto: The Snail gene family and the evolution ofthe neural crest. .. .. 28 Session 2: Neural determination Chair: Claudio D. Stern........................................................................... 31 David J. Anderson: Neural crest stem cells.. .. ... ... ....... ... .. ... ............ ... ... 3 3 Instituto Juan March (Madrid) PAGE Aja y Chitnis: Patteming neurogenesis in the zebrafish embryo. .... ... .... .. ..... 34 Short talk: Caro! Schuurmans: Proneural g enes control the proliferation of cortical progenitors .... ... .. .. .. .......... .. .... ......... ... .......... .......... ............. .. .. 3 6 José A. Cl1mpos-Ortega: Cell type specification in the developing spinal cord of the zebrafi sh... ........................... .. .. .. .. ........ ... ... ....... ... ... ... ..... ....... ... 3 7 Nancy Papalopulu: Spatia l and te mporal c ontrol of neurogenesis in Xenopus e mbr yos. .. .. .. .. .. .. 3 8 Kate G. Storey: Cellular and mol ecul ar mechanisms underlying the progressive generation ofthe spinal cord .. ... ............ .. .. .. .. .. ... .. ... .. .... 4 o Andrew Jarman: Proneural g ene function during Drosophi/a neural spec ificati on... .. ... ..... .. ... .. .. .. .. .. .. ... .. .. .. ..... ... .. 41 Chris Kintner: Regul ati on ofthe Notch pathway during neurogenesis.. ... .. ... ..... 4 3 Session 3: Neural specification and identity Chair: David J. Anderson...................... .. ......... ......................................................... ..... 4 5 Christian Kliimbt: Spec ifi cation a nd differentiation of the Drosophila CNS midline glial ce lis... .. .. .... ... .. .. .......................... .. .... ............. ..... ........... 4 7 Chris Q. Doe: Neural stem cell s sequentially express transcription factors which specify the temporal identity of their neuronal pro gen y. ... ... ....... ...... ......... ... 4 8 William Chia: Cell cycle, cell fa te, asymmetric cell divisions and the generation of neuronal diversity. .............. .. ... ......... ..................... ... .. ... ............. .. 4 9 Cluistine Dambly-Chaudierc: Ne ural identity in the sense organs of fly (lnd fi sh. 5O Angela Giangrande: Fate choi ces and asymmetric cell divisions in fly neural stem ce lis. .. 51. Instituto Juan March (Madrid) PAGE POSTERS............................................................................................. 53 Mark W. Barnett: Xenopus Enhancer of Zeste (XEZ); an anteriorly restricted polycomb gene with a role in neural patteming... ... .. .. ........ .. .. .. .. .. .. ...... .. .... .. ... 55 May-Britt Becker: Functional and structural analysis of the murine homeobox gene lrx2. .. ........ ... ........... .. ....... ... .. .. ........................................................... .. 56 Jo Begbie: Requirement for neural crest in the development of epibranchial ganglia.. .. 57 Yi-Chuan Cheng: Functional analysis ofSox group E genes during gliagenesis. .. .. ... 58 Sébastien Darras: The BMP/CHORDIN antagonism controls sensory pigment cell specification and differentiation in the ascidian embryo.... .. ...... .. .... ...... .. .. .. .. ....... 59 Ruth Diez del Corral: Progression of neurogenesis is regulated by paraxial mesoderm in the chick spinal cord........................... ... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ... .. .. .. 60 Alvaro Glavic: Molecular analysis of the induction and positioning of the midbrain- hindbrain boundary in Xenopus. ... .. .. .. .. .. .. .... .. .. .61 . Stefan Jungbluth: Neural patterning around the vertebrate embryonic midbrain- hindbrain boundary.. .. ........ ... ... ... ............ .. .. .. ... .... .. .. ... .... .. ..... .. ...... ........... 62 Giovanna Liguori: Patteming of anterior neural plate occurs and is maintained in cripto-/- embryos, despite the absence ofthe node ... ...... ............ ...... .. .. .. .. .... ...... 63 Paul J. Scotting: Changes in cSox3 gene expression during patteming of the epibranchial pi acodes and subsequent neurogenesis. ......... 6 4 Cathy Soula: Distinct si tes of origin of oligodendrocytes and somatic motoneurons in the chick spinal cord: oligodendrocytes arise from Nkx2.2-expressing progenitors by a Shh-dependent mechanism.. .... .. .. .. ... ....... .... .................................. .... ... .... 65 Tadmiri R. Venkatesh: The retina aberran! in pattern (rap) gene encodes the Drosophila Fizzy related protein (Fzr) and regulates cell cycle exit and neural pattem formation in the developing eye....... ..... ... .. .... .. ... ... ..... .. .... .. .. .. ... ... .. .. .... 66 Robert Vignali: Induction and patteming of telencephalon in Xenopus /aevis... ..... ... ...... .. .. .. .... .. ... ... ..... .. ... ........ .... .. .. .. .. ... ... .... ... .. ......... 6 7 Tonia Von Ohlen: Dorsoventral patteming within the Drosophi/a CNS: identification oftranscriptional targets ofthe homeodomain proteins lnd and Vnd..... ....... ... .. ... 68 Armin Zülch: - lrxl -Structural and functional analysis of a murine lroquois homeobox gene .... .. .. ..... ................................ ... ... ..................... ...... .................... 69 Instituto Juan March (Madrid) PAGE LIST OF INVITED SPEAKERS................................................................ 71 LIST OF PARTICIPANTS........................................................................ 73 Instituto Juan March (Madrid) lntroduction K. G. Storey and J. Modolell Instituto Juan March (Madrid) 9 Understanding the cellular and molecular mechanisms underlying neural specification is an important and fundamental challenge in Modern Biology. While much progress has recently been made in this area following the characterisation of neural inducing molecules, signalling pathways and transcription factors which mediate vertebrate neural specification, our understanding of the mechanisrns underlying this process springs in large part from studies conducted in the fruit fly, Drosophila melanogaster. It is therefore irnportant and informative to evaluate the similarities and differences manifest at both cellular and molecular levels during the generation of neural tissue in flies and vertebrates. Recent advances in this field include the identification of multiple steps involved in defming vertebrate
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