Hoxd and Gli3-Hoxd interaction roles in Hedgehog regulated digit morphogenesis

Hoxd 和 Gli3-Hoxd 相互作用在 Hedgehog 调节数字形态发生中的作用

• 批准号: 10014540
• 负责人: Susan Mackem
• 金额: $ 59.96万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10014540
• 关键词: Adult; Ambystoma; Amphibia; Anterior; Appearance; Cartilage; Cell Adhesion; Cell Aggregation; Cell Death; Cell physiology; Cessation of life; Chromatin Remodeling Factor; Complex; Congenital Abnormality; Development; Developmental Biology; Digit structure; Disease; Distal; Elements; Ensure; Equilibrium; Erinaceidae; Evolution; Excision; Failure; Feedback; Fibroblast Growth Factor; Finger joint structure; Fingers; GLI3 gene; Gene Dosage; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Transcription; Genomics; Goals; Growth; Homeobox; Homeostasis; Human; Intercept; Joints; Lead; Learning; Length; Limb Bud; Limb Development; Limb structure; Link; Maintenance; Malignant Neoplasms; Mammals; Mesenchyme; Mission; Morphogenesis; Morphology; Mus; Natural regeneration; Neoplasm Metastasis; Neoplasms; Organ; Output; Pathologic; Pathology; Pathway interactions; Pattern; Periodicity; Phalanx; Phalanx of hand; Phase; Physical condensation; Physiological Processes; Play; Positioning Attribute; Process; Proteins; Proteomics; Radial; Regulation; Replication Licensing; Research; Role; Running; SHH gene; Shapes; Signal Transduction; Site; Skeleton; Skin; Structure; Study models; System; Systems Biology; Thumb structure; Tissues; Tumor Biology; Vertebrates; Work; austin; base; beta catenin; cell behavior; cell motility; cellular targeting; design; digit regeneration; gastrointestinal epithelium; genetic approach; insight; joint formation; mutant; neoplastic; neoplastic cell; progenitor; programs; regenerative; selective expression; skeletal; skeletal regeneration; smoothened signaling pathway; transcription factor; tumorigenesis; ulna; Adult; Ambystoma; Amphibia; Anterior; Appearance; Cartilage; Cell Adhesion; Cell Aggregation; Cell Death; Cell physiology; Cessation of life; Chromatin Remodeling Factor; Complex; Congenital Abnormality; Development; Developmental Biology; Digit structure; Disease; Distal; Elements; Ensure; Equilibrium; Erinaceidae; Evolution; Excision; Failure; Feedback; Fibroblast Growth Factor; Finger joint structure; Fingers; GLI3 gene; Gene Dosage; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Transcription; Genomics; Goals; Growth; Homeobox; Homeostasis; Human; Intercept; Joints; Lead; Learning; Length; Limb Bud; Limb Development; Limb structure; Link; Maintenance; Malignant Neoplasms; Mammals; Mesenchyme; Mission; Morphogenesis; Morphology; Mus; Natural regeneration; Neoplasm Metastasis; Neoplasms; Organ; Output; Pathologic; Pathology; Pathway interactions; Pattern; Periodicity; Phalanx; Phalanx of hand; Phase; Physical condensation; Physiological Processes; Play; Positioning Attribute; Process; Proteins; Proteomics; Radial; Regulation; Replication Licensing; Research; Role; Running; SHH gene; Shapes; Signal Transduction; Site; Skeleton; Skin; Structure; Study models; System; Systems Biology; Thumb structure; Tissues; Tumor Biology; Vertebrates; Work; austin; base; beta catenin; cell behavior; cell motility; cellular targeting; design; digit regeneration; gastrointestinal epithelium; genetic approach; insight; joint formation; mutant; neoplastic; neoplastic cell; progenitor; programs; regenerative; selective expression; skeletal; skeletal regeneration; smoothened signaling pathway; transcription factor; tumorigenesis; ulna

5'Hoxd genes play many roles during limb development and may control the effectors of morphogenesis at late stages. How Hoxd genes guide digit morphogenesis and their downstream targets remain enigmatic. Using genetic approaches in mice we find that, in addition to a role in initiating Sonic hedgehog (Shh) expression, 5'Hoxd genes determine the polarity of the primary limb axis early, and regulate digit pattern and morphogenesis at late stages, after digit condensations have already formed, including joint formation and positioning; a major mechanism by which Hoxd genes regulate digit identity. We previously discovered genetic and physical interactions between 5Hoxd and Gli3 that modify Gli3 repressor (Gli3R) function (and hence Shh output), antagonizing Gli3R and potentially converting it to an activator. We find that Gli3-Hox interactions both modulate the polarity of limb axis formation and regulate the pacing of cartilage vs joint formation in digits, which may have relevance for skeletal homeostasis and disease, as well as skeletal birth defects. ....................................................................................................................................................................................................................................................................................................................Role Role of 5'Hoxd genes and Hoxd-Gli3 interaction in determining polarity of primary limb axis formation: In most vertebrates, the primary limb axis runs through the posterior limb with the ulna/digit4 (d4) condensing first. In urodele amphibians such as axolotl, which retain the ability to regenerate limbs as adults, the anterior limb axis is dominant (radius/d2 appear first). Based on altered expression patterns, it has been proposed that the axis shift in Urodeles results from a failure to expand 5'Hoxd gene expression in the late distal limb. We have analyzed limb axis formation in the 5'Hoxd mutant (Hoxd11-13 deleted) and found that the anterior axis forms first as in urodeles. Furthermore, we find that in compound 5'Hoxd;Gli3 mutants, posterior axial dominance is restored. The 5'Hoxd homeobox transcription factors play roles in replication licensing and cell adhesion. Gli3R, expressed anteriorly, also regulates proliferation and condensation, and antagonizes 5'Hoxd function. We are analyzing how changes in the relative timing and rate of proliferation and of cell aggregation/condensation in different zones of the limb bud are altered in these mutants, and if they correlate with anterior vs posterior axial dominance. We propose that the balance between antagonistic 5'Hoxd-Gli3 functions governs the polarity of primary limb axis formation and are investigating the potential relation between altered axis polarity and regenerative capacity. ....................................................................................................................................................................................................................................................................................................................Role of Hoxd genes and Hoxd-Gli3 interaction in cartilage differentiation and joint formation to determine distinct digit identities: Digit identity remains plastic even after the formation of the digit primordial chondrogenic condensations and is regulated by interdigit zones, which are also late sites of 5'Hoxd and Gli3 expression. We found that genetic removal of several Hoxd genes (d11-d13) results in abnormal joint formation, both loss of digit joints and/or abnormal joint position, as well as short, biphalangeal digits. Collaborating with Marian Ros (Univ. Cantabria) we are also examining the role of Hoxa13 in digit formation. Hoxa13 acts upstream of and induces the late phase of Hoxd13 expression and may have a distinct role in regulating the formation of a normal thumb. The canonical Wnt pathway plays an essential role in joint formation and we find that activated beta-catenin restores normal joint formation in the 5'Hoxd mutant digits. But surprisingly, selective activation of stabilized beta-catenin in the interdigital tissues is required for rescue, suggesting that at least some aspects of beta-catenin and 5'Hoxd function in joint formation occur indirectly, via interdigit signaling. Gli3 (the transcriptional effector of Shh and Hoxd protein interactor) also has striking effects on cartilage differentiation and joint formation in digits. During joint formation in digit precursors, Gli3 mutants form abnormal segments with excessive joint formation extending into the cartilage elements. Genetically, the balance between total 5'Hoxd and Gli3 gene dosage regulates the periodic formation of normal joints and the normal 3 bony segments typical of mammalian digits. Our genetic evidence indicates that the Hoxd-Gli3 balance acts indirectly, from interdigital mesenchyme, to modulate Bmp activity and thereby regulate the periodic appearance of digit elements (phalanges) and joints from a digit tip progenitor pool. We are extending our analysis to determine: 1) targets regulated by Gli3-Hoxd interaction and 2) other signaling inputs that regulate the digit tip progenitor pool to determine phalanx number and size. Collaborating with Steve Vokes (UT-Austin) we will examine the role of the chromatin modifier Prmt5, which is selectively expressed in the digit tip progenitors, in maintaining this progenitor pool. Even in mammals, distal digit tips retain a limited capacity for regeneration and understanding the regulation of this distal digit progenitor pool and it's maintenance will provide new insights relevant to skeletal regeneration potential.

5'HOXD基因在肢体发育过程中起着许多作用，并且可以控制晚期形态发生的效应因子。 HOXD基因如何引导数字形态发生及其下游靶标仍然神秘。使用小鼠中的遗传方法，我们发现，除了在启动声音刺猬（SHH）表达中的作用外，5'HOXD基因还确定了早期主要肢体轴的极性，并在阶段调节了后期的数字模式和形态发生，在数字冷凝后已经形成了关节形成和位置，包括关节形成和定位； HOXD基因调节数字身份的主要机制。我们以前在5HOXD和GLI3之间发现了修改GLI3阻遏物（GLI3R）函数（以及SHH输出）之间的遗传和物理相互作用，使GLI3R拮抗并可能将其转换为激活剂。我们发现，GLI3-HOX相互作用既调节肢体轴的极性，又调节了软骨与接头形成的起搏，这可能与骨骼稳态和疾病以及骨骼出生缺陷有关。 ....................................................................................................................................................................................................................................................................................................................Role Role of 5'Hoxd genes and Hoxd-Gli3 interaction in determining polarity of primary limb axis formation: In most vertebrates,初级肢轴首先用尺骨/digit4（D4）凝结。在乌罗德勒两栖动物（例如Axolotl）中，它保留了成年后四肢再生能力的能力，前肢轴是主导的（半径/D2首先出现）。基于变化的表达模式，已经提出，尿素中的轴移动是由于未能在晚期远端肢体中扩展5'HOXD基因表达而导致的。我们已经分析了5'HoxD突变体（HOXD11-13）中的肢体轴的形成，并发现前轴首先形成如尿道中。此外，我们发现在化合物5'HOXD; GLI3突变体中，后轴向优势恢复。 5'HOXD同源词转录因子在复制许可和细胞粘附中起着作用。 GLI3R在前表达，还调节增生和缩合，并拮抗5'HOXD功能。我们正在分析这些突变体的肢体芽不同区域中相对时机和增殖速率的变化以及细胞聚集/凝结的变化，以及它们是否与前轴向优势与前轴向优势相关。我们提出，拮抗5'HoxD-GLI3功能之间的平衡控制原发肢轴形成的极性，并正在研究改变轴极性和再生能力之间的潜在关系。 ....................................................................................................................................................................................................................................................................................................................Role of Hoxd genes and Hoxd-Gli3 interaction in cartilage differentiation and joint formation to determine distinct digit identities: Digit identity remains plastic即使在数字原始软骨凝结形成后，也受到互化区的调节，该区域也是5'HOXD和GLI3表达的晚期位点。我们发现，遗传去除几个HOXD基因（D11-D13）导致关节形成异常，数字关节的丧失和/或异常关节位置以及短毛联旋带数字。与Marian Ros（Univ Cantabria）合作，我们还研究了Hoxa13在数字形成中的作用。 HOXA13在上游并诱导HOXD13表达的后期，并且在调节正常拇指的形成中可能具有独特的作用。规范的Wnt途径在关节形成中起着至关重要的作用，我们发现激活的β-catenin恢复了5'HOXD突变体数字中的正常关节形成。但是令人惊讶的是，需要选择性激活固定的β-catenin在杀虫组织中需要进行救援，这表明至少在关节形成中至少在关节形成中至少某些方面通过互指信号发生了。 GLI3（SHH和HOXD蛋白相互作用器的转录效应子）对数字的软骨分化和关节形成也具有惊人的影响。在数字前体的关节形成期间，GLI3突变体形成异常片段，关节形成过多，延伸到软骨元件中。从遗传上讲，总5'HOXD和GLI3基因剂量之间的平衡调节了正常关节的周期性形成和典型的哺乳动物数字的正常3个骨段。我们的遗传证据表明，HOXD-GLI3平衡间接起作用，从界面间充质到调节BMP活性，从而调节数字元素（phalanges）的周期性外观和来自数字尖端祖细胞库的关节。我们正在扩展分析以确定：1）由GLI3-HOXD相互作用调节的目标和2）其他信号输入，这些信号输入调节了数字尖端祖细胞池以确定phalanx的数量和大小。与史蒂夫·沃克斯（Steve Vokes）（UT-AUSTIN）合作，我们将研究染色质修饰剂PRMT5的作用，该染色质修饰剂PRMT5在数字尖端祖细胞中有选择地表达在维护该祖细胞池中。即使在哺乳动物中，远端数字提示也保留了有限的再生能力，并了解该远端数字祖细胞池的调节及其维护将提供与骨骼再生潜力有关的新见解。