Van Hateren Nick, Belsham Ashley, Randall Victoria, Borycki Anne-Gaëlle
Centre for Developmental Genetics, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield S10 2TN, UK.
Gene Expr Patterns. 2005 Aug;5(6):817-23. doi: 10.1016/j.modgep.2005.03.011.
Groucho-related genes (Grgs) encode transcriptional co-repressors of Lef/Tcf and Hes proteins, which are mediators of Wnt and Notch signalling, respectively. Thus, they are important players in the developmental processes controlled by Wnt and Notch signalling, including lateral inhibition, segmentation and dorso-ventral patterning. We have cloned the avian homologues of Grg genes and examined their expression pattern by whole-mount in situ hybridisation between Hamburger-Hamilton (HH) stages 3 and 24. At HH stage 3, Grg gene expression is detected in the primitive streak and Hensen's node. Later, Grg genes are expressed at high levels in the developing head fold and by HH stage 11, throughout the anterior CNS and in the ventricular zone of the neural tube. In addition, Grg2, Grg4 and Grg5 are expressed in the notochord. In the paraxial mesoderm, Grg genes are activated as soon as somites form. As somites mature, Grg1 and Grg5/AES are expressed predominantly in the medial myotome and dermomyotome, whereas Grg2, Grg3 and Grg4 are expressed throughout the myotome. In HH stage 20 limbs, Grg1, Grg3 and Grg4 transcripts are more abundant in the posterior limb bud, whereas Grg2 and Grg5/AES are expressed throughout. By HH stage 24, Grg1, Grg2 and Grg3 become localized to the dorsal and ventral limb muscle masses, whereas Grg4 and Grg5/AES occupy a more central and ventro-proximal domain, respectively. Overall, our expression data are consistent with a role for Grg genes in Lef/Tcf and Wnt signalling during somitogenesis and with a role in Hes and Notch signalling in neurogenesis.
与格鲁乔相关的基因（Grgs）编码Lef/Tcf和Hes蛋白的转录共抑制因子，它们分别是Wnt和Notch信号通路的介质。因此，它们是Wnt和Notch信号通路控制的发育过程中的重要参与者，包括侧向抑制、体节形成和背腹模式形成。我们克隆了Grg基因的禽类同源物，并通过整胚原位杂交技术在汉堡-汉密尔顿（HH）第3至24阶段检测了它们的表达模式。在HH第3阶段，在原条和亨氏结中检测到Grg基因表达。之后，Grg基因在发育中的头褶中高水平表达，到HH第11阶段，在整个前脑中枢神经系统和神经管的室管膜区表达。此外，Grg2、Grg4和Grg5在脊索中表达。在轴旁中胚层，体节一形成Grg基因就被激活。随着体节成熟，Grg1和Grg5/AES主要在内侧肌节和皮肌节中表达，而Grg2、Grg3和Grg4在整个肌节中表达。在HH第20阶段的肢体中，Grg1、Grg3和Grg4转录本在后肢芽中更为丰富，而Grg2和Grg5/AES在整个后肢芽中表达。到HH第24阶段，Grg1、Grg2和Grg3定位于背侧和腹侧肢体肌肉块，而Grg4和Grg5/AES分别占据更中央和腹侧近端区域。总体而言，我们的表达数据与Grg基因在体节发生过程中参与Lef/Tcf和Wnt信号通路以及在神经发生过程中参与Hes和Notch信号通路的作用一致。
