Early evolution of the LIM homeobox gene family.
Early evolution of the LIM homeobox gene family.
复制标题
DOI：
10.1186/1741-7007-8-4
复制
发表时间：
2010-01-18
期刊：
影响因子：
5.4
通讯作者：
Rokhsar DS
中科院分区：
文献类型：
--
作者：
Srivastava M;Larroux C;Lu DR;Mohanty K;Chapman J;Degnan BM;Rokhsar DS
LIM同源盒（Lhx）转录因子是动物谱系所特有的，在果蝇、线虫和脊椎动物的胚胎发育过程中具有模式作用，在指定神经元身份方面具有保守作用。虽然这个家族的基因在海绵和刺胞动物中有报道，但在非双边门的发育过程中，Lhx家族的表达模式和功能尚不清楚。我们在两种刺胞动物和一种placozoa动物中鉴定了Lhx基因，并报道了Lhx基因在Nematostella和demosponge Amphimedon胚胎发育过程中的表达。6个主要的LIM同型盒亚家族的成员在海葵、线虫和粘毛虫的基因组中都有代表。水螅类刺胞动物Hydra magnipapillata保留了6个Lhx亚科中的4个，但显然失去了另外2个。在昆士兰的单硬壳蠕变海绵Amphimedon中只有三个亚科。在T. adhaerens（一种没有神经元的动物）基因组中，三个不同亚家族的Lhx基因串联簇和一个包含两个LIM结构域的基因表明Lhx亚家族是通过串联复制产生的。这种串联簇在Trichoplax可能是一个残余的原始染色体背景，其中Lhx亚家族首次出现。6个毛虫Lhx基因中的3个在实验室培养的动物中表达，所有的Lhx基因在九头蛇中表达。线虫Lhx基因的表达模式与幼虫和幼年水螅阶段的神经区域相关。在神经海绵A. quenslandica中，三个Lhx基因在发育过程中广泛表达，包括在与幼虫光感环相关的细胞中。Lhx家族在动物进化的早期就扩大和多样化了，在刺胞动物-placozoan-双边动物的最后共同祖先之前，所有六个亚家族都已经分化了。在线虫中，Lhx基因的表达与幼虫和幼年水螅期的神经领地相关。这种模式与线虫属神经系统的可能模式一致。我们提出了一个场景，其中Lhx基因在真生动物的神经模式中起同源作用。
LIM homeobox (Lhx) transcription factors are unique to the animal lineage and have patterning roles during embryonic development in flies, nematodes and vertebrates, with a conserved role in specifying neuronal identity. Though genes of this family have been reported in a sponge and a cnidarian, the expression patterns and functions of the Lhx family during development in non-bilaterian phyla are not known. We identified Lhx genes in two cnidarians and a placozoan and report the expression of Lhx genes during embryonic development in Nematostella and the demosponge Amphimedon. Members of the six major LIM homeobox subfamilies are represented in the genomes of the starlet sea anemone, Nematostella vectensis, and the placozoan Trichoplax adhaerens. The hydrozoan cnidarian, Hydra magnipapillata, has retained four of the six Lhx subfamilies, but apparently lost two others. Only three subfamilies are represented in the haplosclerid demosponge Amphimedon queenslandica. A tandem cluster of three Lhx genes of different subfamilies and a gene containing two LIM domains in the genome of T. adhaerens (an animal without any neurons) indicates that Lhx subfamilies were generated by tandem duplication. This tandem cluster in Trichoplax is likely a remnant of the original chromosomal context in which Lhx subfamilies first appeared. Three of the six Trichoplax Lhx genes are expressed in animals in laboratory culture, as are all Lhx genes in Hydra. Expression patterns of Nematostella Lhx genes correlate with neural territories in larval and juvenile polyp stages. In the aneural demosponge, A. queenslandica, the three Lhx genes are expressed widely during development, including in cells that are associated with the larval photosensory ring. The Lhx family expanded and diversified early in animal evolution, with all six subfamilies already diverged prior to the cnidarian-placozoan-bilaterian last common ancestor. In Nematostella, Lhx gene expression is correlated with neural territories in larval and juvenile polyp stages. This pattern is consistent with a possible role in patterning the Nematostella nervous system. We propose a scenario in which Lhx genes play a homologous role in neural patterning across eumetazoans.
登录
查看更多内容
影响因子：
10.7
作者：
Castresana, J
通讯作者：
Castresana, J
影响因子：
4.1
作者：
Darmer, D;Hauser, F;Grimmelikhuijzen, CJP
通讯作者：
Grimmelikhuijzen, CJP
影响因子：
2.4
作者：
Fritzenwanker, JH;Technau, U
通讯作者：
Technau, U
影响因子：
56.9
作者：
Finnerty, JR;Pang, K;Martindale, MQ
通讯作者：
Martindale, MQ
影响因子：
16.2
作者：
Cassata, G;Kagoshima, H;Bürglin, TR
通讯作者：
Bürglin, TR