Bajpai Ruchi, Sambrani Nagraj, Stadelmayer Bernd, Shashidhara L S
Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India 500 007.
Gene Expr Patterns. 2004 Nov;5(1):113-21. doi: 10.1016/j.modgep.2004.05.005.
Growth and patterning during Drosophila wing development are mediated by signaling from its dorso-ventral (D/V) organizer. Wingless is expressed in the D/V boundary and functions as a morphogen to activate target genes at a distance. Wingless pathway and thereby D/V signaling is negatively regulated by the homeotic gene Ultrabithorax (Ubx) to mediate haltere development. In an enhancer-trap screen to identify genes that show differential expression between wing and haltere discs, we identified CG32062, which codes for a RNA-binding protein. In wing discs, CG32062 is expressed only in non-D/V cells. CG32062 expression in non-D/V cells is dependent on Notch-mediated signaling from the D/V boundary. However, CG32062 expression is independent of Wingless function, thus providing evidence for a second long-range signaling mechanism of the D/V organizer. In haltere discs, CG32062 is negatively regulated by Ubx. The non-cell autonomous nature of Ubx-mediated repression of CG32062 expression suggests that the novel component of D/V signaling is also negatively regulated during haltere specification.
果蝇翅膀发育过程中的生长和模式形成是由其背腹（D/V）组织者发出的信号介导的。无翅基因在D/V边界表达，并作为形态发生素在一定距离外激活靶基因。无翅信号通路以及由此产生的D/V信号受到同源异型基因超双胸（Ubx）的负调控，以介导平衡棒的发育。在一项增强子陷阱筛选中，为了鉴定在翅膀和平衡棒翅芽之间表现出差异表达的基因，我们鉴定出了CG32062，它编码一种RNA结合蛋白。在翅膀翅芽中，CG32062仅在非D/V细胞中表达。CG32062在非D/V细胞中的表达依赖于来自D/V边界的Notch介导的信号。然而，CG32062的表达独立于无翅基因的功能，从而为D/V组织者的第二种远程信号传导机制提供了证据。在平衡棒翅芽中，CG32062受到Ubx的负调控。Ubx介导的对CG32062表达的抑制的非细胞自主性表明，D/V信号的新成分在平衡棒特化过程中也受到负调控。
