Expansion of the SOX gene family predated the emergence of the Bilateria
Expansion of the SOX gene family predated the emergence of the Bilateria
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DOI：
10.1016/j.ympev.2005.12.005
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发表时间：
2006-05-01
影响因子：
4.1
通讯作者：
Manuel, M
中科院分区：
文献类型：
--
作者：
Jager, M;Quéinnec, E;Manuel, M
SOX基因家族的成员参与调节许多发育过程，包括神经元的决定和分化，并参与致癌作用。到目前为止，它们只在两侧门（后口门和原口门）的物种中被发现。为了了解SOX家族的起源，我们使用了基于PCR的策略，以获得28个新的SOX基因HMG结构域的序列从四个非两侧后生动物：两种海绵，一个栉水母和刺胞动物。另外一个SOX序列是从昆虫物种Clytia hemisphaerica的EST序列中检索到的。在这些物种中发现了意想不到的SOX基因多样性，尤其是在刺胞动物和栉水母中。最大似然分析推导出的基因关系的拓扑结构，虽然没有支持的自举值，表明SOX家族开始多样化的后生动物干分支之前，demosponges的分歧，并进一步多样化的真后生动物分支，以及后来在钙海绵，栉水母，刺胞动物和脊椎动物。相比之下，基因丢失似乎发生在线虫和可能在其他原口类谱系，解释他们的SOX基因数量较少。(c)2005年爱思唯尔公司All rights reserved.
Members of the SOX gene family are involved in regulating many developmental processes including neuronal determination and differentiation, and in carcinogenesis. So far they have only been identified in species from the Bilateria (deuterostomes and protostomes). To understand the origins of the SOX family, we used a PCR-based strategy to obtain 28 new sequences of SOX gene HMG domains from four non-bilaterian Metazoa: two sponge species, one ctenophore and one cnidarian. One additional SOX sequence was retrieved from EST sequences of the cmdarian species Clytia hemisphaerica. Unexpected SOX gene diversity was found in these species, especially in the cnidarian and the ctenophore. The topology of gene relationships deduced by Maximum Likelihood analysis, although not supported by bootstrap values, suggested that the SOX family started to diversify in the metazoan stem branch prior to the divergence of demosponges, and that further diversification Occurred in the eumetazoan branch, as well as later in calcisponges, ctenophores, cnidarians and vertebrates. In contrast, gene loss appears to have occurred in the nematode and probably in other protostome lineages, explaining their lower number of SOX genes. (c) 2005 Elsevier Inc. All rights reserved.