Positional Cloning of a Bombyx Wingless Locus flügellos (fl) Reveals a Crucial Role for fringe That Is Specific for Wing Morphogenesis
Positional Cloning of a Bombyx Wingless Locus flügellos (fl) Reveals a Crucial Role for fringe That Is Specific for Wing Morphogenesis
复制标题
DOI：
10.1534/genetics.107.082784
复制
发表时间：
2008-06
期刊：
影响因子：
3.3
通讯作者：
Kaoru Sato;T. Matsunaga;R. Futahashi;T. Kojima;K. Mita;Y. Banno;H. Fujiwara
中科院分区：
文献类型：
--
作者：
Kaoru Sato;T. Matsunaga;R. Futahashi;T. Kojima;K. Mita;Y. Banno;H. Fujiwara
家蚕中FlüGellos(Fl)基因的突变产生了无翅的蛹和蛾，因为翅盘对蜕皮类固醇的反应受到抑制。4个隐性等位基因自发出现，定位于家蚕遗传连锁群10的13.0个等位基因。通过定位克隆，我们证实了控制fl的基因是编码FNG糖基转移酶的条纹基因，该基因参与了Notch信号转导途径的调控。在四个不同的FL等位基因中，我们检测到FNG基因在Flk中大量缺失，在FL、Flo和Fln中发生无义突变。在野生型家蚕中，从四龄到末龄，FNG在翅盘、脑和生殖器官中表达活跃，而在被测其他组织中几乎没有表达。原位杂交结果显示，FNG基因在翼盘的背侧层有表达。无翼(WG)是FNG介导的Notch信号的下游标志，在WT翼盘中定位于背腹侧边界，但在FL翼盘中显著抑制。虽然果蝇FNG的零突变体会导致胚胎后死亡，但FNG功能的丧失只影响翅膀的形态发生，这表明FNG在昆虫组织分化中起着不同的重要作用。
Mutations at the flügellos (fl) locus in Bombyx mori produce wingless pupae and moths because of the repressed response of wing discs to ecdysteroid. Four recessive fl alleles occurred spontaneously and were mapped at 13.0 of the silkworm genetic linkage group 10. By positional cloning, we confirmed that the gene responsible for fl is fringe (fng) encoding Fng glycosyltransferase, which is involved in regulating the Notch signaling pathway. In four different fl alleles, we detected a large deletion of the fng gene in flk and nonsense mutations in fl, flo, and fln. In the wild-type (WT) silkworm, fng is expressed actively in the wing discs, brain, and reproductive organs from the fourth to final instars but barely in the other tissues tested. In situ hybridization showed that fng mRNA is expressed in the dorsal layer of the WT wing discs. The wingless (wg) mRNA, a downstream marker of Fng-mediated Notch signaling, is localized at the dorsoventral boundary in the WT wing discs but repressed markedly in the fl wing discs. Although null mutants of Drosophila fng result in postembryonic lethality, loss of fng function in Bombyx affects only wing morphogenesis, suggesting different essential roles for fng in tissue differentiation among insects.