Harvey R P, Melton D A
Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138.
Cell. 1988 Jun 3;53(5):687-97. doi: 10.1016/0092-8674(88)90087-6.
The structural similarity between Drosophila and vertebrate homeobox genes begs the question of whether the vertebrate gene products affect cell fate and pattern formation. To study the function of the Xenopus homeobox protein, Xhox-1A, we microinjected fertilized Xenopus eggs with an excess of synthetic Xhox-RNA and assayed for effects on development. The predominant phenotype is a disturbance in somite formation. When embryos are injected with Xhox-1A mRNA, but not with control mRNAs, morphogenesis of somites occurs chaotically and individual segments are lost. Histological staining, in situ hybridization, and immunohistochemistry indicate that the disorganized somitic tissue has differentiated into muscle cells. Overall, these results suggest that correct regulation of the Xhox-1A gene may be important for the normal development of the segmented somite pattern in early embryos. Moreover, the inferred role of Xhox-1A in somite formation indicates that there may be molecular parallels between mechanisms of segmentation in flies and vertebrates.
果蝇和脊椎动物同源框基因之间的结构相似性引发了一个问题，即脊椎动物的基因产物是否会影响细胞命运和模式形成。为了研究非洲爪蟾同源框蛋白Xhox-1A的功能，我们向非洲爪蟾受精卵中显微注射过量的合成Xhox-RNA，并检测其对发育的影响。主要表型是体节形成受到干扰。当向胚胎注射Xhox-1A mRNA而非对照mRNA时，体节的形态发生会混乱，个别节段会缺失。组织学染色、原位杂交和免疫组织化学表明，紊乱的体节组织已分化为肌肉细胞。总体而言，这些结果表明，正确调节Xhox-1A基因可能对早期胚胎中分段体节模式的正常发育很重要。此外，Xhox-1A在体节形成中所推断的作用表明，果蝇和脊椎动物的分段机制之间可能存在分子层面的相似之处。
