dissection-lateral-mounting-zebrafish-embryos-analysis-spinal-cord

Dissection and Lateral Mounting of Zebrafish Embryos: Analysis of Spinal Cord Development

The zebrafish spinal cord is an effective investigative model for nervous system research for several reasons. First, genetic, transgenic and gene ...

Skidmore College

&#x57FA;&#x819C;&#x88AB;&#x7EC4;&#x6210;&#x5206;&#x5B50;&#x7684;&#x7269;&#x7406;&#x4EA4;&#x4E92;&#xFF0C;&#x4EE5;&#x5F62;&#x6210;&#x4E00;&#x4E2A;&#x7F51;&#x7EDC;&#xFF0C;&#x5145;&#x5F53;&#x79FB;&#x5F92;&#x652F;&#x67B6;&#x7684;&#x8BB8;&#x591A;&#x5355;&#x5143;&#x683C;&#x7C7B;&#x578B;&#x3002;&#x5728;&#x53D1;&#x5C55;&#x4E2D;&#x56FD;&#x5BB6;&#x5468;&#x56F4;&#x795E;&#x7ECF;&#x7CFB;&#x7EDF;&#xFF0C;&#x795E;&#x7ECF;&#x5143;&#x751F;&#x957F;&#x9525;&#x4ED6;&#x4EEC;&#x8FC1;&#x79FB;&#x662F;&#x86B1;&#x8722;&#x7684;&#x4E0E;&#x57FA;&#x819C;&#x5BC6;&#x5207;&#x76F8;&#x5173;&#x3002;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x662F;&#x57FA;&#x819C;&#x7684;&#x4E3B;&#x8981;&#x7EC4;&#x6210;&#x90E8;&#x5206;&#xFF0C;&#x7A81;&#x8D77;&#x4F53;&#x5916;&#x7684;&#x6709;&#x529B;&#x63A8;&#x52A8;&#x8005;&#x3002;&#x7136;&#x800C;&#xFF0C;&#x5C1A;&#x4E0D;&#x6E05;&#x695A;&#xFF0C;&#x5982;&#x4F55;&#x5EFA;&#x7ACB;&#x5185;&#x57FA;&#x819C;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x7684;&#x5206;&#x5E03;&#x6216;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x7684;&#x6765;&#x6E90;&#x662F;&#x4EC0;&#x4E48;&#x3002;&#x4E3A;&#x4E86;&#x89E3;&#x51B3;&#x8FD9;&#x4E00;&#x95EE;&#x9898;&#xFF0C;&#x86B1;&#x8722;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x4E9A;&#x57FA;&#x57FA;&#x56E0;&#x88AB;&#x514B;&#x9686;&#x3002;&#x5982;&#x6240;&#x6599;&#xFF0C;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x88AB;&#x53D1;&#x73B0;&#x6574;&#x4E2A;&#x80DA;&#x80CE;&#xFF0C;&#x57FA;&#x819C;&#x5185;&#x7279;&#x522B;&#x662F;&#x5728;&#x80A2;&#x82BD;&#xFF0C;&#x5176;&#x4E2D;&#xFF0C;&#x5176;&#x8868;&#x8FBE;&#x5F0F;&#x662F;&#x91CD;&#x5408;&#x7684;&#x4EA7;&#x7269;&#x548C;&#x6307;&#x5BFC; (Til) &#x5148;&#x9A71;&#x795E;&#x7ECF;&#x5143;&#x80EB;&#x9AA8;&#x3002;&#x5947;&#x602A;&#x7684;&#x662F;&#xFF0C;&beta; &#x548C; &gamma; &#x94FE;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x7684;&#x5408;&#x6210;&#x4EC5;&#x9650;&#x4E8E;&#x6D04;&#x6E38;&#x4E2D;&#x80DA;&#x53F6;&#x7EC6;&#x80DE;&#xFF0C;&#x800C;&#x5728;&#x5176;&#x4ED6; nonmigratory &#x7684;&#x7EC4;&#x7EC7;&#xFF0C;&#x5982;&#x4E0A;&#x76AE;&#x7EC6;&#x80DE;&#x548C;&#x63A8;&#x5B9A;&#x808C;&#x8089;&#x3001; &beta; &#x548C; &gamma; &#x94FE;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x7684;&#x68C0;&#x6D4B;&#x4E0D;&#x5230;&#x3002;&#x867D;&#x7136;&#x662F;&#x8FD9;&#x6837;&#xFF0C;&#x57FA;&#x819C;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x514D;&#x75AB;&#x53CD;&#x5E94;&#x51FA;&#x73B0;&#x7EDF;&#x4E00;&#x5E76;&#x4E14;&#x53EF;&#x7528;&#x4F5C;&#x4E3A;&#x57FA;&#x8D28;&#x7684;&#x8F74;&#x7A81;&#x7684;&#x4EA7;&#x7269;&#x3002;

&#x8FC1;&#x79FB;&#x4E2D;&#x80DA;&#x5C42;&#x5EFA;&#x7ACB;&#x5C42;&#x7C98;&#x8FDE;&#x86CB;&#x767D;&#x5747;&#x5300;&#x5206;&#x5E03;&#x5728;&#x53D1;&#x5C55;&#x4E2D;&#x56FD;&#x5BB6;&#x7684;&#x86B1;&#x8722;&#x80DA;&#x80CE;&#x3002;

The basal lamina is composed of molecules which physically interact to form a network that serves as a migrational scaffold for many cell types. In the developing peripheral nervous system of the grasshopper, neuronal growth cones are intimately associated with the basal lamina as they migrate. Laminin is a major component of the basal lamina and is a potent promoter of neurite outgrowth in vitro. However, it is unclear what the source of laminin is or how the distribution of laminin within the basal lamina is established. To address this question, grasshopper laminin subunit genes were cloned. As expected, laminin was found within the basal lamina throughout the embryo, in particular in the limb bud, where its expression is coincident with the outgrowth and guidance of the Tibial (Til) pioneer neurons. Surprisingly, the synthesis of beta and gamma chains of laminin was restricted to migratory mesodermal cells, while in other nonmigratory tissues, such as epithelium and presumptive muscle, beta and gamma chains of laminin were not detected. In spite of this, laminin immunoreactivity in the basal lamina appears uniform and is available as a substrate for axonal outgrowth.

Migrating mesoderm establish a uniform distribution of laminin in the developing grasshopper embryo.

La lame basale est compos&#xE9;e de mol&#xE9;cules qui interagissent physiquement pour former un r&#xE9;seau qui sert de migrationnelle &#xE9;chafaudage pour de nombreux types cellulaires. Dans le d&#xE9;veloppement du syst&#xE8;me nerveux p&#xE9;riph&#xE9;rique de la sauterelle, des c&#xF4;nes de croissance neuronaux sont intimement associ&#xE9;s &#xE0; la lame basale lors de leur migration. La laminine est une composante majeure de la lame basale et est un promoteur puissant de la croissance des neurites in vitro. Toutefois, il n&#x26;#39;est pas clair quelle est la source de la laminine, ou comment la distribution de la laminine dans la membrane basale est &#xE9;tablie. Pour r&#xE9;pondre &#xE0; cette question, les g&#xE8;nes de sauterelles sous-unit&#xE9;s de laminine ont &#xE9;t&#xE9; clon&#xE9;s. Comme pr&#xE9;vu, la laminine a &#xE9;t&#xE9; trouv&#xE9;e dans la lame basale dans tout l&#x26;#39;embryon, en particulier dans l&#x26;#39;oeuf branche, o&#xF9; l&#x26;#39;expression est confondu avec l&#x26;#39;excroissance et le guidage des neurones tibiales pionni&#xE8;res (TIL). &#xC9;tonnamment, la synth&#xE8;se de cha&#xEE;nes b&#xEA;ta et gamma de la laminine a &#xE9;t&#xE9; limit&#xE9;e &#xE0; migratoires cellules m&#xE9;sodermiques, tandis que dans d&#x26;#39;autres tissus non migrateurs, tels que l&#x26;#39;&#xE9;pith&#xE9;lium et le muscle pr&#xE9;somptif, b&#xEA;ta et gamma des cha&#xEE;nes de la laminine n&#x26;#39;ont pas &#xE9;t&#xE9; d&#xE9;tect&#xE9;s. En d&#xE9;pit de cela, la laminine immunor&#xE9;activit&#xE9; dans la lame basale appara&#xEE;t uniforme et est disponible en tant que substrat pour la croissance axonale.

Migration m&#xE9;soderme &#xE9;tablir une r&#xE9;partition uniforme de la laminine dans le d&#xE9;veloppement de l&#x26;#39;embryon Grasshopper

Migrieren von Mesoderm stellen eine gleichm&#xE4;&#xDF;ige Verteilung von Laminin in der sich entwickelnden Embryo Heuschrecke.

La lamina basale &egrave; composta di molecole che interagiscono fisicamente per formare una rete che serve come un ponteggio migrational per molti tipi di cellule. In via di sviluppo sistema nervoso periferico della cavalletta, coni di crescita neuronale sono intimamente associati con la lamina basale come migrano. La laminina &egrave; una componente importante della lamina basale ed &egrave; un potente promotore della crescita dei neuriti in vitro. Tuttavia, non &egrave; chiaro qual &egrave; l&#39;origine della laminina o come viene stabilita la distribuzione di laminina all&#39;interno della lamina basale. Per rispondere a questa domanda, sono stati clonati geni subunit&agrave; di cavalletta laminina. Come previsto, la laminina &egrave; stata trovata all&#39;interno della lamina basale in tutto l&#39;embrione, in particolare sul nascere dell&#39;arto, dove la sua espressione &egrave; coincidente con l&#39;escrescenza e guida di Tibial (Til), pionieri dei neuroni. Sorprendentemente, la sintesi delle catene beta e gamma di laminina &egrave; stata limitata a celle mesodermica migratori, mentre in altri tessuti, migratore, come epitelio e muscolo presuntiva, beta e catene gamma di laminina non sono state rilevate. Nonostante ci&ograve;, laminina immunoreattivit&agrave; della lamina basale appare uniforme ed &egrave; disponibile come substrato per la crescita assonale.

La migrazione del mesoderma stabilire una distribuzione uniforme della laminina nell&#39;embrione in via di sviluppo grasshopper.

&#x57FA;&#x5E95;&#x819C;&#x306F;&#x3001;&#x7269;&#x7406;&#x7684;&#x306B;&#x591A;&#x304F;&#x306E;&#x7D30;&#x80DE;&#x30BF;&#x30A4;&#x30D7;&#x306E;&#x904A;&#x8D70;&#x306E;&#x8DB3;&#x5834;&#x3068;&#x3057;&#x3066;&#x6A5F;&#x80FD;&#x3059;&#x308B;&#x30CD;&#x30C3;&#x30C8;&#x30EF;&#x30FC;&#x30AF;&#x3092;&#x5F62;&#x6210;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x3059;&#x308B;&#x5206;&#x5B50;&#x3067;&#x69CB;&#x6210;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x5F7C;&#x3089;&#x304C;&#x79FB;&#x884C;&#x3059;&#x308B;&#x30D0;&#x30C3;&#x30BF;&#x306E;&#x958B;&#x767A;&#x672B;&#x68A2;&#x795E;&#x7D4C;&#x7CFB;&#x3067;&#x306F;&#x3001;&#x30CB;&#x30E5;&#x30FC;&#x30ED;&#x30F3;&#x306E;&#x6210;&#x9577;&#x5186;&#x9310;&#x306F;&#x5BC6;&#x63A5;&#x306B;&#x57FA;&#x5E95;&#x819C;&#x306B;&#x95A2;&#x9023;&#x4ED8;&#x3051;&#x3089;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306F;&#x57FA;&#x5E95;&#x819C;&#x306E;&#x4E3B;&#x8981;&#x6210;&#x5206;&#x3067;&#x3042;&#x308A;&#x3001;in vitro&#x306B;&#x304A;&#x3051;&#x308B;&#x795E;&#x7D4C;&#x7A81;&#x8D77;&#x4F38;&#x9577;&#x306E;&#x5F37;&#x529B;&#x306A;&#x30D7;&#x30ED;&#x30E2;&#x30FC;&#x30BF;&#x30FC;&#x3067;&#x3042;&#x308B;&#x3002;&#x3057;&#x304B;&#x3057;&#x3001;&#x305D;&#x308C;&#x306F;&#x57FA;&#x5E95;&#x819C;&#x5185;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306E;&#x5206;&#x5E03;&#x304C;&#x78BA;&#x7ACB;&#x3055;&#x308C;&#x3066;&#x3044;&#x308B;&#x3082;&#x306E;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306E;&#x30BD;&#x30FC;&#x30B9;&#x304C;&#x3042;&#x308B;&#x304B;&#x3069;&#x3046;&#x304B;&#x306F;&#x4E0D;&#x660E;&#x3067;&#x3042;&#x308B;&#x3002;&#x3053;&#x306E;&#x554F;&#x984C;&#x306B;&#x5BFE;&#x51E6;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x3001;&#x30D0;&#x30C3;&#x30BF;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x30B5;&#x30D6;&#x30E6;&#x30CB;&#x30C3;&#x30C8;&#x907A;&#x4F1D;&#x5B50;&#x304C;&#x30AF;&#x30ED;&#x30FC;&#x30CB;&#x30F3;&#x30B0;&#x3057;&#x305F;&#x3002;&#x4E88;&#x60F3;&#x901A;&#x308A;&#x3001;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306F;&#x3001;&#x305D;&#x306E;&#x5F0F;&#x306F;&#x811B;&#x9AA8;&#xFF08;TIL&#xFF09;&#x306E;&#x30D1;&#x30A4;&#x30AA;&#x30CB;&#x30A2;&#x30CB;&#x30E5;&#x30FC;&#x30ED;&#x30F3;&#x306E;&#x7A81;&#x8D77;&#x4F38;&#x9577;&#x3084;&#x30AC;&#x30A4;&#x30C0;&#x30F3;&#x30B9;&#x3068;&#x4E00;&#x81F4;&#x3059;&#x308B;&#x80A2;&#x82BD;&#x306B;&#x304A;&#x3044;&#x3066;&#x3001;&#x7279;&#x306B;&#x80DA;&#x5168;&#x4F53;&#x306B;&#x57FA;&#x5E95;&#x819C;&#x5185;&#x306B;&#x898B;&#x3064;&#x304B;&#x308A;&#x307E;&#x3057;&#x305F;&#x3002;&#x305D;&#x306E;&#x3088;&#x3046;&#x306A;&#x4E0A;&#x76AE;&#x3068;&#x63A8;&#x5B9A;&#x7B4B;&#x8089;&#x306E;&#x3088;&#x3046;&#x306A;&#x4ED6;&#x306E;nonmigratory&#x7D44;&#x7E54;&#x3067;&#x306F;&#x3001;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306E;&#x3B2;&#x3001;&#x3B3;&#x9396;&#x306F;&#x691C;&#x51FA;&#x3055;&#x308C;&#x306A;&#x304B;&#x3063;&#x305F;&#x9593;&#x306B;&#x9A5A;&#x304F;&#x3079;&#x304D;&#x3053;&#x3068;&#x306B;&#x3001;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306E;&#x3B2;&#x304A;&#x3088;&#x3073;&#x3B3;&#x9396;&#x306E;&#x5408;&#x6210;&#x306F;&#x3001;&#x6E21;&#x308A;&#x9CE5;&#x306E;&#x4E2D;&#x80DA;&#x8449;&#x7D30;&#x80DE;&#x306B;&#x5236;&#x9650;&#x3055;&#x308C;&#x3066;&#x3044;&#x307E;&#x3057;&#x305F;&#x3002;&#x3053;&#x308C;&#x306B;&#x3082;&#x304B;&#x304B;&#x308F;&#x3089;&#x305A;&#x3001;&#x57FA;&#x5E95;&#x819C;&#x306E;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306E;&#x514D;&#x75AB;&#x53CD;&#x5FDC;&#x306F;&#x3001;&#x5747;&#x4E00;&#x306B;&#x8868;&#x793A;&#x3055;&#x308C;&#x3001;&#x8EF8;&#x7D22;&#x4F38;&#x9577;&#x306E;&#x305F;&#x3081;&#x306E;&#x57FA;&#x8CEA;&#x3068;&#x3057;&#x3066;&#x5229;&#x7528;&#x53EF;&#x80FD;&#x3067;&#x3059;&#x3002;

&#x958B;&#x767A;&#x30D0;&#x30C3;&#x30BF;&#x80DA;&#x306B;&#x304A;&#x3051;&#x308B;&#x30E9;&#x30DF;&#x30CB;&#x30F3;&#x306E;&#x5747;&#x4E00;&#x306A;&#x5206;&#x5E03;&#x3092;&#x78BA;&#x7ACB;&#x4E2D;&#x80DA;&#x8449;&#x3078;&#x306E;&#x79FB;&#x884C;

&#xB9CE;&#xC740; &#xC140; &#xD615;&#xC2DD;&#xC758; migrational &#xBE44; &#xACC4; &#xC5ED;&#xD560;&#xC744; &#xD558;&#xB294; &#xB124;&#xD2B8;&#xC6CC;&#xD06C; &#xD615;&#xC131;&#xC744; &#xBB3C;&#xB9AC;&#xC801;&#xC73C;&#xB85C; &#xC0C1;&#xD638; &#xC791;&#xC6A9; &#xD558;&#xB294; &#xBD84;&#xC790;&#xC758; &#xAE30;&#xC800; lamina &#xAD6C;&#xC131; &#xB429;&#xB2C8;&#xB2E4;. &#xBA54;&#xB69C;&#xAE30;&#xC758; &#xAC1C;&#xBC1C; &#xB9D0; &#xCD08; &#xC2E0; &#xACBD;&#xACC4;&#xC5D0;&#xC11C; &#xC2E0;&#xACBD; &#xC131;&#xC7A5; &#xC6D0;&#xBFD4;&#xC73C;&#xB85C; &#xB9C8;&#xC774;&#xADF8;&#xB808;&#xC774;&#xC158;&#xD560; &#xAE30;&#xC800; lamina &#xBC00;&#xC811; &#xD558; &#xAC8C; &#xC5F0;&#xAD00; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;. Laminin &#xAE30;&#xC800; lamina&#xC758; &#xC8FC;&#xC694; &#xAD6C;&#xC131; &#xC694;&#xC18C; &#xC774;&#xBA70; neurite &#xD30C;&#xC0DD;&#xBB3C; &#xCCB4; &#xC678;&#xC758; &#xAC15;&#xB825;&#xD55C; &#xBAA8;&#xD130;. &#xADF8;&#xB7EC;&#xB098;, &#xADF8;&#xAC83;&#xC740; &#xD558;&#xC9C0; &#xBD84;&#xBA85; laminin&#xC758; &#xC18C;&#xC2A4; &#xB610;&#xB294; &#xAE30;&#xC800; lamina &#xC774;&#xB0B4; laminin&#xC758; &#xBC30;&#xD3EC; &#xC124;&#xC815; &#xBC29;&#xBC95;&#xC785;&#xB2C8;&#xB2E4;. &#xC774; &#xBB38;&#xC81C;&#xB97C; &#xD574;&#xACB0; &#xD558;&#xAE30; &#xC704;&#xD574; &#xBA54;&#xB69C;&#xAE30; laminin &#xC18C; &#xB2E8;&#xC704; &#xC720;&#xC804;&#xC790; &#xBCF5;&#xC81C; &#xB41C;. &#xC608;&#xC0C1; &#xB300;&#xB85C; laminin&#xC774; &#xCC3E;&#xC558;&#xC2B5;&#xB2C8;&#xB2E4; &#xD0DC;&#xC544;, &#xAC78;&#xCCD0; &#xAE30;&#xC800; lamina&#xC5D0;&#xC11C; &#xD2B9;&#xD788; &#xADF8; &#xD45C;&#xD604; &#xD30C;&#xC0DD;&#xBB3C;&#xACFC; &#xC9C0;&#xB3C4; (&#xD2F8;) &#xAC1C;&#xCC99;&#xC790; &#xB274;&#xB7F0; Tibial &#xC81C;&#xC5B4;&#xC810;&#xC740; &#xC0AC;&#xC9C0; &#xC0C8;&#xC2F9;&#xC5D0;&#xC11C;. &#xB180;&#xB78D;&#xAC8C;&#xB3C4;, laminin&#xC758; &#xBCA0;&#xD0C0; &#xBC0F; &#xAC10;&#xB9C8; &#xCCB4;&#xC778; &#xD569;&#xC131; &#xC0C1;&#xD53C;&#xC640; &#xCD94;&#xC815; &#xADFC;&#xC721;, &#xBCA0;&#xD0C0; nonmigratory &#xB2E4;&#xB978; &#xC870;&#xC9C1;&#xC5D0;&#xC11C; &#xCCA0;&#xC0C8; mesodermal &#xC140;&#xC73C;&#xB85C; &#xC81C;&#xD55C; &#xB418;&#xC5C8;&#xACE0; laminin&#xC758; &#xAC10;&#xB9C8; &#xC0AC;&#xC2AC; &#xAC80;&#xC0C9; &#xB418;&#xC9C0; &#xB410;&#xB2E4;. &#xAE30;&#xC800; lamina&#xC5D0;&#xC11C; laminin immunoreactivity &#xC720;&#xB2C8;&#xD3FC; &#xB098;&#xD0C0;&#xB098;&#xACE0; axonal &#xD30C;&#xC0DD;&#xBB3C;&#xC5D0; &#xB300; &#xD55C; &#xAE30;&#xD310;&#xC73C;&#xB85C; &#xC0AC;&#xC6A9;&#xD560; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;.

&#xB9C8;&#xC774;&#xADF8;&#xB808;&#xC774;&#xC158; mesoderm &#xBC1C;&#xC804; &#xBA54;&#xB69C;&#xAE30; &#xBC30;&#xC544;&#xC5D0;&#xC11C; laminin&#xC758; &#xADE0;&#xC77C; &#xD55C; &#xBD84;&#xD3EC;&#xB97C; &#xC124;&#xC815; &#xD569;&#xB2C8;&#xB2E4;.

La l&#xE1;mina basal est&#xE1; compuesto de mol&#xE9;culas que interaccionan f&#xED;sicamente para formar una red que sirve como un andamio migratorio para muchos tipos de c&#xE9;lulas. En el desarrollo del sistema nervioso perif&#xE9;rico de los saltamontes, los conos de crecimiento neuronales est&#xE1;n &#xED;ntimamente asociados con la l&#xE1;mina basal, ya que migrar. La laminina es un componente principal de la l&#xE1;mina basal y es un potente promotor de crecimiento neur&#xED;tico in vitro. Sin embargo, no est&#xE1; claro cu&#xE1;l es la fuente de la laminina es o c&#xF3;mo la distribuci&#xF3;n de laminina en la l&#xE1;mina basal se ha establecido. Para abordar esta cuesti&#xF3;n, saltamontes genes de la subunidad laminina fueron clonados. Como era de esperar, la laminina se encuentra dentro de la l&#xE1;mina basal en todo el embri&#xF3;n, en particular en la yema de la extremidad, donde su expresi&#xF3;n es coincidente con el resultado y la orientaci&#xF3;n de las neuronas pioneras tibiales (TIL). Sorprendentemente, la s&#xED;ntesis de cadenas beta y gamma de laminina se limita a las c&#xE9;lulas migratorias mesod&#xE9;rmicos, mientras que en otros tejidos no migratorias, tales como el epitelio y el m&#xFA;sculo presuntivo, beta y gamma cadenas de laminina no se detectaron. A pesar de esto, inmunoreactividad laminina en la l&#xE1;mina basal aparece uniforme y est&#xE1; disponible como un sustrato para crecimiento axonal.

Migraci&#xF3;n de mesodermo establecer una distribuci&#xF3;n uniforme de laminina en el embri&#xF3;n en desarrollo Grasshopper

&#x5982;&#x795E;&#x7ECF;&#x5143;&#x5728;&#x5F00;&#x53D1;&#x8FC7;&#x7A0B;&#x4E2D;&#x6269;&#x5C55;&#x5230;&#x5176;&#x76EE;&#x6807;&#x7684;&#x795E;&#x7ECF;&#x8F74;&#x7A81;&#xFF0C;&#x751F;&#x957F;&#x9525;&#x5FC5;&#x987B;&#x8C03;&#x6574;&#x5176;&#x65B9;&#x5411;&#x7684;&#x8FC1;&#x79FB;&#x4E2D;&#x80DE;&#x5916;&#x5BFC;&#x5411;&#x4FE1;&#x53F7;&#x7684;&#x54CD;&#x5E94;&#x3002;&#x89E3;&#x5256;&#x7684;&#x7EC6;&#x80DE;&#x548C;&#x5206;&#x5B50;&#x673A;&#x5236;&#xFF0C;&#x8FD9;&#x4E2A;&#x590D;&#x6742;&#x7684;&#x8FC7;&#x7A0B;&#xFF0C;&#x91C7;&#x7528;&#x4E86;&#x5404;&#x79CD;&#x5404;&#x6837;&#x7684;&#x6A21;&#x578B;&#x7CFB;&#x7EDF;&#x3002;&#x4E00;&#x5236;&#x5907;&#xFF0C;&#x53D1;&#x5C55;&#x4E2D;&#x56FD;&#x5BB6;&#x7684;&#x86B1;&#x8722;&#x80A2;&#x82BD;&#xFF0C;&#x5DF2;&#x8BC1;&#x660E;&#x82E5;&#x5E72;&#x4F18;&#x52BF;&#xFF0C;&#x7528;&#x6765;&#x68C0;&#x67E5;&#x751F;&#x957F;&#x9525;&#x6307;&#x5BFC;&#x4E0E;&#x4F53;&#x5185;&#x7684;&#x52A8;&#x529B;&#x673A;&#x5236;&#x3002;&#x7B2C;&#x4E00;&#xFF0C;&#x89C4;&#x6A21;&#x8F83;&#x5927;&#x7684;&#x80DA;&#x80CE;&#x795E;&#x7ECF;&#x7CFB;&#x7EDF;&#x5141;&#x8BB8;&#x76F4;&#x63A5;&#x6210;&#x50CF;&#x7684;&#x56FA;&#x5B9A;&#x548C;&#x6D3B;&#x7684;&#x795E;&#x7ECF;&#x5143;&#x4F53;&#x5185;&#x3002;&#x7B2C;&#x4E8C;&#xFF0C;&#x5728;&#x80A2;&#x4F53;&#x82BD;&#x4E2D;&#x751F;&#x6210;&#x7684;&#x5916;&#x5468;&#x795E;&#x7ECF;&#x9AD8;&#x5EA6;&#x9648;&#x89C4;&#x5B9A;&#x578B;&#x3002;&#x7B2C;&#x4E09;&#xFF0C;&#x4E0D;&#x53D8;&#x7684;&#x80DA;&#x80CE;&#x53EF;&#x4EE5;&#x4E3A;&#x5929;&#xFF0C;&#x5141;&#x8BB8;&#x76F8;&#x5F53;&#x5BB9;&#x6613;&#x6270;&#x52A8;&#x7CBE;&#x786E;&#x53D1;&#x80B2;&#x9636;&#x6BB5;&#x57F9;&#x517B;&#x3002;&#x7B2C;&#x56DB;&#xFF0C;&#x7531;&#x4E8E;&#x5939;&#x5C42;&#x7684;&#x6613;&#x7528;&#x6027;&#xFF0C;&#x4F17;&#x591A;&#x7684;&#x7EC6;&#x80DE;&#x751F;&#x7269;&#x5B66;&#x548C;&#x5206;&#x5B50;&#x6280;&#x672F;&#x53EF;&#x4EE5;&#x5229;&#x7528;&#x80A2;&#x4F53;&#x542B;&#x82DE;&#x5F85;&#x653E;&#x3002;&#x6700;&#x540E;&#xFF0C;&#x8F74;&#x7A81;&#x5BFC;&#x5411;&#x5206;&#x5B50;&#x548C;&#x673A;&#x5236;&#x5B88;&#x6052;&#x86B1;&#x8722;&#x548C;&#x5176;&#x4ED6;&#x751F;&#x7269;&#x4F53;&#xFF0C;&#x5305;&#x62EC;&#x810A;&#x690E;&#x52A8;&#x7269;&#x4E4B;&#x95F4;&#x3002;

&#x80EB;&#x9AA8; 1 &#x5148;&#x9A71;&#x9014;&#x5F84;&#xFF1A; &#x4F53;&#x5185;&#x6A21;&#x578B;&#x795E;&#x7ECF;&#x5143;&#x4EA7;&#x7269;&#x548C;&#x6307;&#x5BFC;&#x3002;

As neurons extend axons to their targets during development, growth cones must reorient their direction of migration in response to extracellular guidance cues. A variety of model systems have been employed in order to dissect the cellular and molecular mechanisms that underlie this complex process. One preparation, the developing grasshopper limb bud, has proved to offer a number of advantages in which to examine mechanisms of growth cone guidance and motility in vivo. First, the relatively large size of the embryonic nervous system allows for straightforward imaging of both fixed and live neurons in vivo. Second, the peripheral nerves generated in the limb bud are highly stereotyped. Third, intact embryos can be cultured for a period of days, allowing for fairly easy perturbations at precise developmental stages. Fourth, due to the ease of dissection, numerous cell biological and molecular techniques can be utilized in the limb bud. Finally, axon guidance molecules and mechanisms are conserved between grasshoppers and other organism, including vertebrates.

The tibial-1 pioneer pathway: an in vivo model for neuronal outgrowth and guidance.

Comme les neurones s&#39;&eacute;tendent des axones vers leurs cibles au cours du d&eacute;veloppement, c&ocirc;nes de croissance doivent r&eacute;orienter leur direction des migrations en r&eacute;ponse &agrave; des signaux extracellulaires d&#39;orientation. Une vari&eacute;t&eacute; de syst&egrave;mes mod&egrave;les ont &eacute;t&eacute; utilis&eacute;s afin de diss&eacute;quer les m&eacute;canismes cellulaires et mol&eacute;culaires qui sous-tendent ce processus complexe. Une pr&eacute;paration, le bourgeon de membre sauterelle en d&eacute;veloppement, s&#39;est av&eacute;r&eacute; offrent de nombreux avantages permettant d&#39;examiner les m&eacute;canismes d&#39;orientation de c&ocirc;ne de croissance et de la motilit&eacute; in vivo. Tout d&#39;abord, la taille relativement importante du syst&egrave;me nerveux embryonnaire permet d&#39;imagerie simple des neurones fixes et live in vivo. Deuxi&egrave;mement, les nerfs p&eacute;riph&eacute;riques g&eacute;n&eacute;r&eacute;es dans le bourgeon de membre sont tr&egrave;s st&eacute;r&eacute;otyp&eacute;s. Embryons intacts, troisi&egrave;me peuvent &ecirc;tre cultiv&eacute;es pour une p&eacute;riode de jours, ce qui permet des perturbations assez faciles &agrave; des stades de d&eacute;veloppement pr&eacute;cis. Quatri&egrave;mement, en raison de la facilit&eacute; de dissection, de nombreuses techniques biologiques et mol&eacute;culaires de cellule peuvent &ecirc;tre utilis&eacute;s dans le bourgeon de membre. Enfin, les m&eacute;canismes et mol&eacute;cules de guidage axonal sont conserv&eacute;es entre les sauterelles et autres micro-organismes, notamment des vert&eacute;br&eacute;s.

La voie pionni&egrave;re tibiale-1: un mod&egrave;le in vivo pour l&#39;excroissance des neurones et leurs conseils.

Wie Neuronen Axone auf ihre Ziele bei der Entwicklung zu erweitern, m&uuml;ssen Wachstum Zapfen ihre Richtung der Migration als Reaktion auf extrazellul&auml;re Anleitung Hinweise neu orientieren. Eine Vielzahl von Modellsystemen wurden eingestellt, um die zellul&auml;ren und molekularen Mechanismen zu sezieren, die diesen komplexen Prozess zugrunde liegen. Eine Zubereitung, die Entwicklung Heuschrecke Gliedma&szlig;en Knospe, erwies sich bieten eine Reihe von Vorteilen, um die Mechanismen des Wachstums Kegel Anleitung und Motilit&auml;t in-vivo zu untersuchen. Erstens erm&ouml;glicht die relativ gro&szlig;e Gr&ouml;&szlig;e des embryonalen Nervensystems f&uuml;r einfache Imaging sowohl live als auch feste Neuronen in-vivo. Zweitens sind die peripheren Nerven erzeugt im Keim Gliedma&szlig;en sehr klischeehaft. Dritte, intakte Embryonen k&ouml;nnen f&uuml;r einen Zeitraum von Tagen, damit ziemlich einfach Perturbationen auf pr&auml;zise Entwicklungsstadien kultiviert werden. Viertens k&ouml;nnen wegen der Leichtigkeit des Sezierens, zahlreiche Zelle biologische und molekulare Techniken in den Gliedma&szlig;en-Knospe genutzt werden. Schlie&szlig;lich sind Axon Guidance Molek&uuml;le und Mechanismen zwischen Heuschrecken und anderen Organismus, einschlie&szlig;lich Wirbeltieren konserviert.

Der Pionier tibial-1-Weg: ein in-vivo Modell f&uuml;r neuronale Auswuchs und Anleitung.

Come i neuroni estendono assoni ai loro bersagli durante lo sviluppo, coni di crescita devono riorientare la loro direzione di migrazione in risposta a segnali extracellulari di orientamento. Una variet&agrave; di sistemi di modello sono state impiegate per sezionare i meccanismi cellulari e molecolari che sono alla base di questo complesso processo. Una preparazione, la cavalletta arto germoglio in via di sviluppo, ha dimostrato di offrire una serie di vantaggi in cui esaminare i meccanismi di crescita cono guida e motilit&agrave; in vivo. In primo luogo, le dimensioni relativamente grandi del sistema nervoso embrionale consente semplice imaging dei neuroni fissi e diretta in vivo. In secondo luogo, i nervi periferici generati sul nascere dell&#39;arto sono altamente stereotipati. Terzi, intatti gli embrioni possono essere colta per un periodo di giorni, permettendo di perturbazioni abbastanza facile a precise fasi di sviluppo. Quarto, a causa della facilit&agrave; di dissezione, numerose tecniche di biologico e molecolare delle cellule possono essere utilizzate sul nascere dell&#39;arto. Infine, meccanismi e axon guidance molecole sono conservate tra cavallette e altri organismi, compresi i vertebrati.

Via pioniere del tibiale-1: un modello in vivo per escrescenza neuronale e di orientamento.

&#x6210;&#x9577;&#x5186;&#x9310;&#x30CB;&#x30E5;&#x30FC;&#x30ED;&#x30F3;&#x8EF8;&#x7D22;&#x306E;&#x76EE;&#x6A19;&#x3092;&#x958B;&#x767A;&#x4E2D;&#x306B;&#x62E1;&#x5F35;&#x3059;&#x308B;&#x3088;&#x3046;&#x306B;&#x3001;&#x79FB;&#x884C;&#x306B;&#x5FDC;&#x7B54;&#x3057;&#x3066;&#x7D30;&#x80DE;&#x5916;&#x8A98;&#x5C0E;&#x624B;&#x306E;&#x5F7C;&#x3089;&#x306E;&#x65B9;&#x5411;&#x306E;&#x5411;&#x304D;&#x3092;&#x5909;&#x66F4;&#x3059;&#x308B;&#x5FC5;&#x8981;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;&#x3055;&#x307E;&#x3056;&#x307E;&#x306A;&#x30E2;&#x30C7;&#x30EB; &#x30B7;&#x30B9;&#x30C6;&#x30E0;&#x306F;&#x3001;&#x3053;&#x306E;&#x8907;&#x96D1;&#x306A;&#x30D7;&#x30ED;&#x30BB;&#x30B9;&#x306E;&#x6839;&#x5E95;&#x306B;&#x3042;&#x308B;&#x7D30;&#x80DE;&#x304A;&#x3088;&#x3073;&#x5206;&#x5B50;&#x30E1;&#x30AB;&#x30CB;&#x30BA;&#x30E0;&#x3092;&#x89E3;&#x5256;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x63A1;&#x7528;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;1 &#x3064;&#x306E;&#x6E96;&#x5099;&#x3001;&#x767A;&#x5C55;&#x9014;&#x4E0A;&#x306E;&#x30D0;&#x30C3;&#x30BF;&#x80A2;&#x82BD;&#x3092;&#x6210;&#x9577;&#x5186;&#x9310;&#x30AC;&#x30A4;&#x30C0;&#x30F3;&#x30B9;&#x3068; in vivo &#x3067;&#x306E;&#x904B;&#x52D5;&#x306E;&#x30E1;&#x30AB;&#x30CB;&#x30BA;&#x30E0;&#x3092;&#x8ABF;&#x67FB;&#x3059;&#x308B;&#x5229;&#x70B9;&#x306E;&#x6570;&#x3092;&#x63D0;&#x4F9B;&#x3057;&#x3066;&#x8A3C;&#x660E;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x307E;&#x305A;&#x3001;&#x840C;&#x82BD;&#x671F;&#x306E;&#x795E;&#x7D4C;&#x7CFB;&#x306E;&#x6BD4;&#x8F03;&#x7684;&#x5927;&#x304D;&#x306A;&#x30B5;&#x30A4;&#x30BA;&#x56FA;&#x5B9A;&#x3068;&#x30E9;&#x30A4;&#x30D6;&#x306E;&#x4E21;&#x65B9;&#x306E;&#x30CB;&#x30E5;&#x30FC;&#x30ED;&#x30F3;&#x306E;&#x7C21;&#x5358;&#x30A4;&#x30E1;&#x30FC;&#x30B8;&#x30F3;&#x30B0;&#x7528; in vivo &#x3067;&#x3067;&#x304D;&#x307E;&#x3059;&#x3002;&#x7B2C;&#x4E8C;&#x306B;&#x3001;&#x80A2;&#x82BD;&#x306E;&#x751F;&#x6210;&#x3055;&#x308C;&#x305F;&#x672B;&#x68A2;&#x795E;&#x7D4C;&#x306F;&#x975E;&#x5E38;&#x306B;&#x30B9;&#x30C6;&#x30EC;&#x30AA;&#x30BF;&#x30A4;&#x30D7;&#x3067;&#x3059;&#x3002;&#x7B2C;&#x4E09;&#x306B;&#x3001;&#x305D;&#x306E;&#x307E;&#x307E;&#x306E;&#x80DA;&#x306F;&#x304B;&#x306A;&#x308A;&#x7C21;&#x5358;&#x64FE;&#x4E71;&#x3092;&#x6B63;&#x78BA;&#x306A;&#x767A;&#x9054;&#x6BB5;&#x968E;&#x3067;&#x53EF;&#x80FD;&#x306B;&#x3059;&#x308B;&#x65E5;&#x306E;&#x671F;&#x9593;&#x57F9;&#x990A;&#x3059;&#x308B;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x307E;&#x3059;&#x3002;&#x7B2C;&#x56DB;&#x306B;&#x3001;&#x90ED;&#x6E05;&#x3092;&#x5BB9;&#x6613;&#x3059;&#x308B;&#x305F;&#x3081;&#x3001;&#x591A;&#x6570;&#x306E;&#x7D30;&#x80DE;&#x751F;&#x7269;&#x5B66;&#x30FB;&#x5206;&#x5B50;&#x6280;&#x8853;&#x80A2;&#x82BD;&#x3067;&#x5229;&#x7528;&#x3067;&#x304D;&#x307E;&#x3059;&#x3002;&#x6700;&#x5F8C;&#x306B;&#x3001;&#x8EF8;&#x7D22;&#x30AC;&#x30A4;&#x30C0;&#x30F3;&#x30B9;&#x5206;&#x5B50;&#x3068;&#x30E1;&#x30AB;&#x30CB;&#x30BA;&#x30E0;&#x306F;&#x3001;&#x30D0;&#x30C3;&#x30BF;&#x3084;&#x810A;&#x690E;&#x52D5;&#x7269;&#x3092;&#x542B;&#x3080;&#x3001;&#x4ED6;&#x306E;&#x751F;&#x7269;&#x306E;&#x9593;&#x4FDD;&#x5B58;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;

&#x811B;&#x9AA8; 1 &#x30D1;&#x30A4;&#x30AA;&#x30CB;&#x30A2;&#x7D4C;&#x8DEF;: &#x795E;&#x7D4C;&#x4F38;&#x9577;&#x3068;&#x30AC;&#x30A4;&#x30C0;&#x30F3;&#x30B9;&#x306E; in vivo &#x3067;&#x306E;&#x30E2;&#x30C7;&#x30EB;&#x306F;&#x3002;

&#xC2E0;&#xACBD; &#xC138;&#xD3EC; &#xCD95; &#xC0AD; &#xADF8;&#xB4E4;&#xC758; &#xBAA9;&#xD45C;&#xB97C; &#xAC1C;&#xBC1C; &#xD558;&#xB294; &#xB3D9;&#xC548; &#xD655;&#xC7A5;&#xC73C;&#xB85C; &#xC131;&#xC7A5; &#xC6D0;&#xBFD4; &#xC138;&#xD3EC; &#xC678; &#xC548;&#xB0B4; &#xC2E0;&#xD638;&#xC5D0; &#xB300; &#xD55C; &#xC751;&#xB2F5;&#xC5D0;&#xC11C; &#xADF8;&#xB4E4;&#xC758; &#xBC29;&#xD5A5;&#xC758; &#xBC29;&#xD5A5;&#xC744; &#xC0C8;&#xB85C; &#xC124;&#xC815; &#xD574;&#xC57C; &#xD569;&#xB2C8;&#xB2E4;. &#xB2E4;&#xC591; &#xD55C; &#xBAA8;&#xB378; &#xC2DC;&#xC2A4;&#xD15C;&#xC740;&#xC774; &#xBCF5;&#xC7A1; &#xD55C; &#xACFC;&#xC815;&#xC758; &#xAE30;&#xCD08;&#xAC00; &#xB418;&#xB294; &#xC138;&#xD3EC;&#xC9C8;&#xC774; &#xACE0; &#xBD84;&#xC790; &#xBA54;&#xCEE4;&#xB2C8;&#xC998;&#xC744; &#xD574; &#xBD80; &#xD558;&#xAE30; &#xC704;&#xD574; &#xACE0;&#xC6A9; &#xB418;&#xC5B4;. &#xD55C; &#xC900;&#xBE44;, &#xAC1C;&#xBC1C; &#xBA54;&#xB69C;&#xAE30; &#xB2E4;&#xB9AC; &#xBD09; &#xC81C;&#xACF5; &#xD558;&#xB294; &#xB2E4;&#xC591; &#xD55C; &#xC131;&#xC7A5; &#xC6D0;&#xBFD4; &#xC9C0;&#xB3C4; &#xC6B4;&#xB3D9; &#xC131; in vivo&#xC758; &#xBA54;&#xCEE4;&#xB2C8;&#xC998;&#xC744; &#xAC80;&#xC0AC; &#xD558;&#xB294; &#xC7A5;&#xC810; &#xC785;&#xC99D; &#xD558;&#xACE0;&#xC788;&#xB2E4;. &#xCCAB;&#xC9F8;, &#xBC30;&#xC544; &#xC2E0;&#xACBD; &#xC2DC;&#xC2A4;&#xD15C;&#xC758; &#xBE44;&#xAD50;&#xC801; &#xD070; &#xD06C;&#xAE30; &#xACE0;&#xC815; &#xBC0F; &#xB77C;&#xC774;&#xBE0C; &#xB274;&#xB7F0;&#xC758; &#xAC04;&#xB2E8; &#xC774;&#xBBF8;&#xC9D5; vivo&#xC5D0;&#xC11C; &#xD5C8;&#xC6A9;&#xD569;&#xB2C8;&#xB2E4;. &#xB458;&#xC9F8;, &#xB2E4;&#xB9AC; &#xB1CC;&#xC5D0;&#xC11C; &#xC0DD;&#xC131; &#xB41C; &#xC8FC;&#xBCC0; &#xC2E0;&#xACBD;&#xC740; &#xB9E4;&#xC6B0; &#xC9C4;&#xBD80;. &#xC14B;&#xC9F8;, &#xADF8;&#xB300;&#xB85C; &#xD0DC;&#xC544; &#xC77C;, &#xC815;&#xD655;&#xD55C; &#xBC1C;&#xB2EC; &#xB2E8;&#xACC4;&#xC5D0;&#xC11C; &#xBE44;&#xAD50;&#xC801; &#xC27D;&#xAC8C; &#xBB3C;&#xACB0;&#xC5D0; &#xB300; &#xD55C; &#xC218;&#xC758; &#xAE30;&#xAC04;&#xC5D0; &#xB300; &#xD55C; &#xAD50;&#xC591; &#xB420; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;. &#xB137;&#xC9F8;, &#xD574; &#xBD80;&#xC758; &#xC6A9;&#xC774;&#xC131;&#xC73C;&#xB85C; &#xC778;&#xD574; &#xC218;&#xB9CE;&#xC740; &#xC138;&#xD3EC; &#xC0DD;&#xBB3C;&#xD559; &#xBC0F; &#xBD84;&#xC790; &#xAE30;&#xC220;&#xC740; &#xC0AC;&#xC9C0; &#xC0C8;&#xC2F9;&#xC5D0;&#xC11C; &#xC774;&#xC6A9;&#xD558;&#xC2E4; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;. &#xB9C8;&#xC9C0;&#xB9C9;&#xC73C;&#xB85C;, &#xCD95; &#xC0AD; &#xC9C0;&#xB3C4; &#xBD84;&#xC790; &#xBC0F; &#xBA54;&#xCEE4;&#xB2C8;&#xC998; &#xBA54;&#xB69C;&#xAE30;&#xC640; &#xCC99;&#xCD94;&#xB97C; &#xD3EC;&#xD568; &#xD55C; &#xB2E4;&#xB978; &#xC720;&#xAE30; &#xCCB4; &#xC0AC;&#xC774;&#xC758; &#xBCF4;&#xC874; &#xB429;&#xB2C8;&#xB2E4;.

1 Tibial &#xAC1C;&#xCC99;&#xC790; &#xD1B5;&#xB85C;: &#xC2E0;&#xACBD; &#xD30C;&#xC0DD;&#xBB3C; &#xBC0F; &#xC9C0;&#xCE68;&#xC5D0; &#xB300; &#xD55C; in vivo &#xBAA8;&#xB378;.

Como las neuronas extienden axones sus objetivos durante el desarrollo, conos de crecimiento deben reorientar su direcci&oacute;n de la migraci&oacute;n en respuesta a se&ntilde;ales extracelulares de orientaci&oacute;n. Una variedad de sistemas modelo han sido empleados para diseccionar los mecanismos celulares y moleculares que subyacen a este complejo proceso. Una preparaci&oacute;n, el esbozo del saltamontes en desarrollo, ha demostrado para ofrecer una serie de ventajas que examinar mecanismos de orientaci&oacute;n del cono de crecimiento y motilidad in vivo. En primer lugar, el tama&ntilde;o relativamente grande del sistema nervioso embrionario permite la proyecci&oacute;n de imagen directa de neuronas tanto fijas como vivos in vivo. En segundo lugar, los nervios perif&eacute;ricos que se generan en el esbozo de la extremidad son altamente estereotipados. Embriones en tercer lugar, intactos pueden ser cultivados por un per&iacute;odo de d&iacute;as, teniendo en cuenta las perturbaciones bastante f&aacute;ciles en etapas de desarrollo precisas. En cuarto lugar, debido a la facilidad de la disecci&oacute;n, pueden utilizarse numerosas t&eacute;cnicas biol&oacute;gicas y moleculares de la c&eacute;lula del esbozo. Finalmente, mecanismos y mol&eacute;culas de orientaci&oacute;n del ax&oacute;n se conservan entre los saltamontes y otro organismo, incluidos los vertebrados.

El camino pionero tibial-1: un modelo in vivo por consecuencia neuronal y orientaci&oacute;n.

While Wnt/beta-catenin signaling is known to be involved in the development of neural crest cells in zebrafish, it is unclear which Wnts are involved, and when they are required. To address these issues we employed a zebrafish line that was transgenic for an inducible inhibitor of Wnt/beta-catenin signaling, and inhibited endogenous Wnt/beta-catenin signaling at discrete times in development. Using this approach, we defined a critical period for Wnt signaling in the initial induction of neural crest, which is distinct from the later period of development when pigment cells are specified from neural crest. Blocking Wnt signaling during this early period interfered with neural crest formation without blocking development of dorsal spinal neurons. Transplantation experiments suggest that neural crest precursors must directly transduce a Wnt signal. With regard to identifying which endogenous Wnt is responsible for this initial critical period, we established that wnt8 is expressed in the appropriate time and place to participate in this process. Supporting a role for Wnt8, blocking its function with antisense morpholino oligonucleotides eliminates initial expression of neural crest markers. Taken together, these results demonstrate that Wnt signals are critical for the initial induction of zebrafish neural crest and suggest that this signaling pathway plays reiterated roles in its development.

Reiterated Wnt signaling during zebrafish neural crest development.

Canonical Wnt signaling can regulate proliferation and patterning in the developing spinal cord, but the relationship between these functions has remained elusive. It has been difficult to separate the distinct activities of Wnts because localized changes in proliferation could conceivably alter patterning, and gain and loss of function experiments have resulted in both types of defects. To resolve this issue we have investigated canonical Wnt signaling in the zebrafish spinal cord using multiple approaches. We demonstrate that Wnt signaling is required initially for proliferation throughout the entire spinal cord, and later for patterning dorsal progenitor domains. Furthermore, we find that spinal cord patterning is normal in embryos after cell division has been pharmacologically blocked. Finally, we determine the transcriptional mediators of Wnt signaling that are responsible for patterning and proliferation. We show that tcf7 gene knockdown results in dorsal patterning defects without decreasing the mitotic index in dorsal domains. In contrast, tcf3 gene knockdown results in a reduced mitotic index without affecting dorsal patterning. Together, our work demonstrates that proliferation and patterning in the developing spinal cord are separable events that are regulated independently by Wnt signaling.

Proliferation and patterning are mediated independently in the dorsal spinal cord downstream of canonical Wnt signaling.

The Lef/Tcf factor Tcf3 is expressed throughout the developing vertebrate central nervous system (CNS), but its function and transcriptional targets are uncharacterized. Tcf3 is thought to mediate canonical Wnt signaling, which functions in CNS patterning, proliferation and neurogenesis. In this study, we examine Tcf3 function in the zebrafish spinal cord, and find that this factor does not play a general role in patterning, but is required for the proper expression of Dbx genes in intermediate progenitors. In addition, we show that Tcf3 is required to inhibit premature neurogenesis in spinal progenitors by repressing sox4a, a known mediator of spinal neurogenesis. Both of these functions are mediated by Tcf3 independently of canonical Wnt signaling. Together, our data indicate a novel mechanism for the regulation of neurogenesis by Tcf3-mediated repression.

Tcf3 inhibits spinal cord neurogenesis by regulating sox4a expression.

Growth cone navigation across the vertebrate midline is critical in the establishment of nervous system connectivity. While midline crossing is achieved through coordinated signaling of attractive and repulsive cues, this has never been demonstrated at the single cell level. Further, though growth cone responsiveness to guidance cues changes after crossing the midline, it is unclear whether midline crossing itself is required for subsequent guidance decisions in vivo. In the zebrafish, spinal commissures are initially formed by a pioneer neuron called CoPA (Commissural Primary Ascending). Unlike in other vertebrate models, CoPA navigates the midline alone, allowing for single-cell analysis of axon guidance mechanisms.

Midline crossing is not required for subsequent pathfinding decisions in commissural neurons.

Calcium, a ubiquitous intracellular signaling molecule, controls a diverse array of cellular processes. Consequently, cells have developed strategies to modulate the shape of calcium signals in space and time. The force generating machinery in muscle is regulated by the influx and efflux of calcium ions into the muscle cytoplasm. In order for efficient and effective muscle contraction to occur, calcium needs to be rapidly, accurately and reliably regulated. The mechanisms underlying this highly regulated process are not fully understood. Here, we show that the Caenorhabditis elegans homolog of the giant muscle protein obscurin, UNC-89, is required for normal muscle cell architecture. The large immunoglobulin domain-rich isoforms of UNC-89 are critical for sarcomere and sarcoplasmic reticulum organization. Furthermore, we have found evidence that this structural organization is crucial for excitation-contraction coupling in the body wall muscle, through the coordination of calcium signaling. Thus, our data implicates UNC-89 in maintaining muscle cell architecture and that this precise organization is essential for optimal calcium mobilization and efficient and effective muscle contraction.

Large isoforms of UNC-89 (obscurin) are required for muscle cell architecture and optimal calcium release in Caenorhabditis elegans.

Despite recommendations, there have been few efforts to apply the community-based participatory research (CBPR) approach in the development, implementation, and evaluation of community gardens.

Exploring community gardens in a health disparate population: findings from a mixed methods pilot study.

Zebrafish provide researchers and students alike with an excellent model of vertebrate nervous system development due to a high degree of conserved developmental mechanisms and transparent embryos that develop in synchrony. In these laboratory exercises, undergraduate students explore cell biological concepts while performing hypothesis-driven novel research utilizing methodologies such as immunofluorescence, confocal microscopy, image analysis, pharmacology, and basic statistics. In the first block of exercises, students perform anti-acetylated tubulin (anti-AT) immunofluorescence, identify spinal tracts and neuronal subtypes, and perform conventional and confocal microscopy. Building on knowledge acquired in the first block of exercises, during the second block, students subsequently perform pharmacological activation of Wnt signaling through lithium chloride treatments, and assess nervous system integrity through anti-AT immunofluorescence. Students perform various quantitative methods and apply statistics to determine outcomes of Wnt activation. In their final laboratory report, students contextualize their results with foundations of molecular mechanisms of nervous system development. In sum, these exercises offer undergraduate students a model of independent research at the graduate level.

Article	Year
Migrating mesoderm establish a uniform distribution of laminin in the developing grasshopper embryo. Developmental biology\| PubMed ID: 12217318	2002
The tibial-1 pioneer pathway: an in vivo model for neuronal outgrowth and guidance. Methods in cell biology\| PubMed ID: 12884692	2003
Reiterated Wnt signaling during zebrafish neural crest development. Development (Cambridge, England)\| PubMed ID: 14973296	2004
Proliferation and patterning are mediated independently in the dorsal spinal cord downstream of canonical Wnt signaling. Developmental biology\| PubMed ID: 18062957	2008
Tcf3 inhibits spinal cord neurogenesis by regulating sox4a expression. Development (Cambridge, England)\| PubMed ID: 19176587	2009
Midline crossing is not required for subsequent pathfinding decisions in commissural neurons. Neural development\| PubMed ID: 22672767	2012
Large isoforms of UNC-89 (obscurin) are required for muscle cell architecture and optimal calcium release in Caenorhabditis elegans. PloS one\| PubMed ID: 22768340	2012
Exploring community gardens in a health disparate population: findings from a mixed methods pilot study. Progress in community health partnerships : research, education, and action\| PubMed ID: 22820225	2012
Activation of Wnt signaling using lithium chloride: inquiry-based undergraduate laboratory exercises. Zebrafish\| PubMed ID: 23098089	2012

Jennifer Bonner

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