Department of Craniofacial Biology, School of Dental Medicine, University of Colorado, Denver, Colorado, USA.
Dev Dyn. 2013 Jul;242(7):817-31. doi: 10.1002/dvdy.23969. Epub 2013 Jun 3.
The regulatory mechanisms underpinning facial development are conserved between diverse species. Therefore, results from model systems provide insight into the genetic causes of human craniofacial defects. Previously, we generated a comprehensive dataset examining gene expression during development and fusion of the mouse facial prominences. Here, we used this resource to identify genes that have dynamic expression patterns in the facial prominences, but for which only limited information exists concerning developmental function.
This set of ∼80 genes was used for a high-throughput functional analysis in the zebrafish system using Morpholino gene knockdown technology. This screen revealed three classes of cranial cartilage phenotypes depending upon whether knockdown of the gene affected the neurocranium, viscerocranium, or both. The targeted genes that produced consistent phenotypes encoded proteins linked to transcription (meis1, meis2a, tshz2, vgll4l), signaling (pkdcc, vlk, macc1, wu:fb16h09), and extracellular matrix function (smoc2). The majority of these phenotypes were not altered by reduction of p53 levels, demonstrating that both p53-dependent and -independent mechanisms were involved in the craniofacial abnormalities.
This Morpholino-based screen highlights new genes involved in development of the zebrafish craniofacial skeleton with wider relevance to formation of the face in other species, particularly mouse and human.
面部发育的调控机制在不同物种之间是保守的。因此，模型系统的研究结果为研究人类颅面缺陷的遗传原因提供了线索。此前，我们生成了一个综合数据集，研究了小鼠面部突起发育和融合过程中的基因表达。在这里，我们利用这一资源来鉴定在面部突起中具有动态表达模式的基因，但这些基因的发育功能信息有限。
利用斑马鱼系统中的 Morpholino 基因敲低技术，对大约 80 个基因进行了高通量功能分析。该筛选揭示了三种颅软骨表型，这取决于基因敲低是否影响了神经颅、咽颅或两者。产生一致表型的靶向基因编码与转录（meis1、meis2a、tshz2、vgll4l）、信号（pkdcc、vlk、macc1、wu：fb16h09）和细胞外基质功能（smoc2）相关的蛋白。这些表型中的大多数都不受 p53 水平降低的影响，这表明 p53 依赖性和非依赖性机制都参与了颅面异常的形成。
这项基于 Morpholino 的筛选突出了新的基因，这些基因参与了斑马鱼颅面骨骼的发育，与其他物种，特别是小鼠和人类的面部形成具有更广泛的相关性。
