现代昆虫唯一已知的背侧附器是翅膀及其衍生物，它们仅仅出现在其第二及第三胸节上。然而，在化石记录中翅状垫却存在于昆虫其它的无翅节段上。
现在，Takahiro Ohde及其同事证明，2个分别出现在黄粉虫甲虫 Tenebrio molitor 第一胸节和腹节上的特别翅状垫可通过减少该昆虫中 Hox 基因的表达而被诱导成为翅状附器。相关论文发表在3月14日的Science上。
据这些研究人员披露，这些身体区域仍然保持着某种可被开启而萌发出新附器的翅膀发育机制。他们的发现意味着这些区域——也被称为序列翼翅同系物——并没有在进化中丧失，而是进行了修改以允许出现极为多样的昆虫身体构造。Ohde及其他的研究人员提出，其它昆虫物种身体上的无翅节段可能也有长出翅膀的潜力。(生物谷Bioon.com)
DOI: 10.1126/science.1234219
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PMID:
Insect Morphological Diversification Through the Modification of Wing Serial Homologs
Takahiro Ohde, Toshinobu Yaginuma, Teruyuki Niimi.
Fossil insects living some 350 million years ago show winglike pads on all thoracic and abdominal segments, which suggests their serial homology. It remains unclear whether winglike structures in nonwinged segments have been lost or modified through evolution. Here, we identified a ventral/lateral part of the body wall on the first thoracic segment, the hypomeron, and pupal dorsolateral denticular outgrowths as wing serial homologs in the mealworm beetle Tenebrio molitor. Both domains transform into winglike structures under Hox RNA interference conditions. Gene expression and functional analyses revealed central roles for the key wing selector genes, vestigial and scalloped, in the hypomeron and the denticular outgrowth formation. We propose that modification, rather than loss, of dorsal appendages has provided an additional diversifying mechanism of insect body plan.
