Daulny A, Rappailles A, Landemarre L, Locker D, Decoville M
Centre de Biophysique Moléculaire, CNRS UPR 4301, conventionnée avec l'Université d'Orléans, 45071 Orléans, France.
Genesis. 2003 Jun;36(2):104-13. doi: 10.1002/gene.10201.
DSP1 is an HMG-box protein which has been implicated in the regulation of homeotic genes in Drosophila melanogaster. Here we report that DSP1 is also involved in the regulation of the kni gap gene. Analysis of the phenotype of a null mutation of dsp1 (dsp1(1)) reveals that the absence of maternal DSP1 results in A4 segmentation defects that are correlated with a diminution of the kni expression domain. Genetic interaction studies demonstrate that a bcd mutation enhances the A4 defect of dsp1(1). We present in vitro and in vivo evidences for a direct interaction between DSP1 and Bicoid, mediated by the BCD homeodomain and the HMG box of DSP1. Finally, we show by immunoprecipitation of cross-linked chromatin the association of DSP1 with the kni-regulating region and discuss the potential mechanism of DSP1-mediated activation of kni.
DSP1是一种HMG盒蛋白，它与黑腹果蝇同源异型基因的调控有关。在此我们报告DSP1也参与了kni间隙基因的调控。对dsp1无效突变（dsp1(1)）的表型分析表明，母源DSP1的缺失会导致A4节段缺陷，这与kni表达域的缩小相关。遗传相互作用研究表明，bcd突变会增强dsp1(1)的A4缺陷。我们提供了体外和体内证据，证明DSP1与双胸蛋白之间存在直接相互作用，这种相互作用由双胸蛋白的同源结构域和DSP1的HMG盒介导。最后，我们通过交联染色质的免疫沉淀显示了DSP1与kni调控区域的关联，并讨论了DSP1介导的kni激活的潜在机制。
