The feelgood mutation in zebrafish dysregulates COPII-dependent secretion of select extracellular matrix proteins in skeletal morphogenesis.
The feelgood mutation in zebrafish dysregulates COPII-dependent secretion of select extracellular matrix proteins in skeletal morphogenesis.
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DOI：
10.1242/dmm.007625
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发表时间：
2011-11
影响因子：
4.3
通讯作者：
Knapik EW
中科院分区：
文献类型：
--
作者：
Melville DB;Montero-Balaguer M;Levic DS;Bradley K;Smith JR;Hatzopoulos AK;Knapik EW
颅面和骨骼畸形占大多数出生缺陷。许多疾病的表型已被归因于细胞外基质（ECM）的异常合成，维持和组成，但导致这些ECM缺陷的分子和细胞机制仍然知之甚少。由于软骨细胞发育成熟阶段的缺陷，斑马鱼感觉良好突变体表现出严重畸形的头部骨骼和缩短的体长。在体内分析揭示了积压的II型和IV型胶原蛋白在粗面内质网（ER）中发现的那些相似的外壳蛋白II复合物（COPII）缺陷的细胞。感觉良好的突变阻碍了ECM中的胶原沉积，但小货物和其他大ECM蛋白如层粘连蛋白到细胞外空间的运输不受影响。我们证明，斑马鱼的感觉良好的突变导致转录因子Creb3l2的DNA结合结构域内的单个氨基酸取代。我们发现Creb3l2选择性地调节编码不同COPII蛋白（sec23a，sec23b和sec24d）的基因的表达，但没有发现其调节sec24c表达的证据。此外，我们没有检测到激活的ER应激反应基因，尽管细胞内积累的胶原蛋白和突出的骨骼缺陷。启动子反式激活试验表明，Creb3l2感觉良好的变体是一个亚型等位基因，保留约50%的转录活性。感觉良好表型的转基因拯救实验恢复颅面发育，说明Creb3l2转录活性的精确水平对骨骼发育至关重要。我们的研究结果表明，Creb3l2调制的可用性COPII机器在组织和货物的具体方式。这些发现可以更好地了解人类颅面和骨骼出生缺陷的病因，以及与ECM沉积失调有关的成人发病疾病，如关节炎，纤维化或骨质疏松症。
Craniofacial and skeletal dysmorphologies account for the majority of birth defects. A number of the disease phenotypes have been attributed to abnormal synthesis, maintenance and composition of extracellular matrix (ECM), yet the molecular and cellular mechanisms causing these ECM defects remain poorly understood. The zebrafish feelgood mutant manifests a severely malformed head skeleton and shortened body length due to defects in the maturation stage of chondrocyte development. In vivo analyses reveal a backlog of type II and type IV collagens in rough endoplasmic reticulum (ER) similar to those found in coat protein II complex (COPII)-deficient cells. The feelgood mutation hinders collagen deposition in the ECM, but trafficking of small cargos and other large ECM proteins such as laminin to the extracellular space is unaffected. We demonstrate that the zebrafish feelgood mutation causes a single amino acid substitution within the DNA-binding domain of transcription factor Creb3l2. We show that Creb3l2 selectively regulates the expression of genes encoding distinct COPII proteins (sec23a, sec23b and sec24d) but find no evidence for its regulation of sec24c expression. Moreover, we did not detect activation of ER stress response genes despite intracellular accumulation of collagen and prominent skeletal defects. Promoter trans-activation assays show that the Creb3l2 feelgood variant is a hypomorphic allele that retains approximately 50% of its transcriptional activity. Transgenic rescue experiments of the feelgood phenotype restore craniofacial development, illustrating that a precise level of Creb3l2 transcriptional activity is essential for skeletogenesis. Our results indicate that Creb3l2 modulates the availability of COPII machinery in a tissue- and cargo-specific manner. These findings could lead to a better understanding of the etiology of human craniofacial and skeletal birth defects as well as adult-onset diseases that are linked to dysregulated ECM deposition, such as arthritis, fibrosis or osteoporosis.
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影响因子：
30.8
作者：
Boyadjiev, Simeon A.;Fromme, J. Christopher;Eyaid, Wafaa
通讯作者：
Eyaid, Wafaa
影响因子：
30.8
作者：
Lang, Michael R.;Lapierre, Lynne A.;Knapik, Ela W.
通讯作者：
Knapik, Ela W.
影响因子：
12.3
作者：
Bradley, Kevin M.;Elmore, J. Bradford;Smith, Jeffrey R.
通讯作者：
Smith, Jeffrey R.
影响因子：
5.3
作者：
Kondo, Shinichi;Saito, Atsushi;Imaizumi, Kazunori
通讯作者：
Imaizumi, Kazunori
DOI：
10.1126/science.1176009
发表时间：
2009-11-27
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Hynes RO
通讯作者：
Hynes RO