Mazet Françoise, Yu Jr Kai, Liberles David A, Holland Linda Z, Shimeld Sebastian M
School of Animal and Microbial Sciences, The University of Reading, P.O. Box 228 Whiteknights, RG6 6AJ Reading, UK.
Gene. 2003 Oct 16;316:79-89. doi: 10.1016/s0378-1119(03)00741-8.
The Forkhead or Fox gene family encodes putative transcription factors. There are at least four Fox genes in yeast, 16 in Drosophila melanogaster (Dm) and 42 in humans. Recently, vertebrate Fox genes have been classified into 17 groups named FoxA to FoxQ. Here, we extend this analysis to invertebrates, using available sequences from D. melanogaster, Anopheles gambiae (Ag), Caenorhabditis elegans (Ce), the sea squirt Ciona intestinalis (Ci) and amphioxus Branchiostoma floridae (Bf), from which we also cloned several Fox genes. Phylogenetic analyses lend support to the previous overall subclassification of vertebrate genes, but suggest that four subclasses (FoxJ, L, N and Q) could be further subdivided to reflect their relationships to invertebrate genes. We were unable to identify orthologs of Fox subclasses E, H, I, J, M and Q1 in D. melanogaster, A. gambiae or C. elegans, suggesting either considerable loss in ecdysozoans or the evolution of these subclasses in the deuterostome lineage. Our analyses suggest that the common ancestor of protostomes and deuterostomes had a minimum complement of 14 Fox genes.
叉头或Fox基因家族编码假定的转录因子。酵母中至少有4个Fox基因，黑腹果蝇（Dm）中有16个，人类中有42个。最近，脊椎动物的Fox基因已被分为17组，命名为FoxA到FoxQ。在这里，我们利用黑腹果蝇、冈比亚按蚊（Ag）、秀丽隐杆线虫（Ce）、海鞘玻璃海鞘（Ci）和文昌鱼佛罗里达文昌鱼（Bf）的现有序列，将这种分析扩展到无脊椎动物，我们还从这些物种中克隆了几个Fox基因。系统发育分析支持了先前对脊椎动物基因的总体亚分类，但表明四个亚类（FoxJ、L、N和Q）可以进一步细分，以反映它们与无脊椎动物基因的关系。我们无法在黑腹果蝇、冈比亚按蚊或秀丽隐杆线虫中鉴定出Fox亚类E、H、I、J、M和Q1的直系同源基因，这表明蜕皮动物中这些亚类有相当大的缺失，或者这些亚类在后口动物谱系中发生了进化。我们的分析表明，原口动物和后口动物的共同祖先至少有14个Fox基因。
