Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK.
Dev Biol. 2010 Apr 15;340(2):234-48. doi: 10.1016/j.ydbio.2010.01.015. Epub 2010 Jan 21.
FoxC, FoxF, FoxL1 and FoxQ1 genes have been shown to be clustered in some animal genomes, with mesendodermal expression hypothesised as a selective force maintaining cluster integrity. Hypotheses are, however, constrained by a lack of data from the Lophotrochozoa. Here we characterise members of the FoxC, FoxF, FoxL1 and FoxQ1 families from the annelid Capitella teleta and the molluscs Lottia gigantea and Patella vulgata. We cloned FoxC, FoxF, FoxL1 and FoxQ1 genes from C. teleta, and FoxC, FoxF and FoxL1 genes from P. vulgata, and established their expression during development. We also examined their genomic organisation in C. teleta and L. gigantea, and investigated local syntenic relationships. Our results show mesodermal and anterior gut expression is a common feature of these genes in lophotrochozoans. In L. gigantea FoxC, FoxF and FoxL1 are closely linked, while in C. teleta Ct-foxC and Ct-foxL1 are closely linked, with Ct-foxF and Ct-foxQ1 on different scaffolds. Adjacent to these genes there is limited evidence of local synteny. This demonstrates conservation of genomic organisation and expression of these genes can be traced in all three bilaterian Superphyla. These data are evaluated against competing theories for the long-term maintenance of gene clusters.
FoxC、FoxF、FoxL1 和 FoxQ1 基因已被证明在一些动物基因组中聚集在一起，假设中胚层和内胚层的表达是维持簇完整性的选择力。然而，由于缺乏来自两侧对称动物门的数据，这些假设受到了限制。在这里，我们从环节动物门的 Capiteletate 以及软体动物门的 Lottia gigantea 和 Patella vulgata 中鉴定了 FoxC、FoxF、FoxL1 和 FoxQ1 家族的成员。我们从 C. teleta 克隆了 FoxC、FoxF、FoxL1 和 FoxQ1 基因，从 P. vulgata 克隆了 FoxC、FoxF 和 FoxL1 基因，并在发育过程中建立了它们的表达。我们还研究了它们在 C. teleta 和 L. gigantea 中的基因组组织，并调查了局部同线性关系。我们的研究结果表明，这些基因在两侧对称动物中具有中胚层和前肠表达的共同特征。在 L. gigantea 中，FoxC、FoxF 和 FoxL1 紧密连锁，而在 C. teleta 中，Ct-foxC 和 Ct-foxL1 紧密连锁，Ct-foxF 和 Ct-foxQ1 位于不同的支架上。这些基因附近的局部同线性证据有限。这表明这些基因的基因组组织和表达在所有三个两侧对称动物超门中都得到了保守。这些数据是针对基因簇长期维持的竞争理论进行评估的。
