Spalt-mediated dve repression is a critical regulatory motif and coordinates with Iroquois complex in Drosophila vein formation

Abstract

Veins are longitudinal cuticular structures that maintain shape of the wing. Drosophila melanogaster has six longitudinal veins (L1-L6) and two cross veins. The Zn-finger transcription factors of Spalt-complex (Sal) are required for positioning of the L2 and L5, and the homeodomain transcription factors of Iroquois complex (Iro-C) are required for formation of the L3 and L5 veins. The homeodomain transcriptional repressor Defective proventriculus (Dve) is uniformly expressed in the wing pouch of the larval imaginal disc. However, dve mutant wings showed loss of the L2 and L5, but not of the L3 and L4 veins. Temporal dve knockdown experiments indicate that the Dve activity is required for vein formation from late third larval instar to the prepupal stage. In the prepupal wing, Dve expression becomes nearly complementary to that of Sal through the Sal-mediated dve repression. Furthermore, coexpression of Dve and Iro-C relieved of Sal-mediated repression is required for the L5 formation in a dose-dependent manner. The relationship between Sal, Dve, and Iro-C in wing vein specification is quite similar to that in ommatidial cell-type specification. Our results provide information about the conserved function of dve regulatory motifs in cell differentiation.

The wing imaginal disc

“…( Mullor et al 1997 ; Strigini and Cohen 1997 ; Biehs et al 1998 ; Vervoort et al 1999 ; Mohler et al 2000 ). The more peripheral veins, L2 and L5, are positioned by Dpp signaling, which acts through regulation of several genes expressed in broad domains, including the Aristaless, Brk, Omb, Optix, Salm, and Salr transcription factors, which then define along their borders stripes of gene expression that will become L2 and L5 ( Gómez-Skarmeta and Modolell 1996 ; Sturtevant et al 1997 ; Lunde et al 1998 ; de Celis and Barrio 2000 ; Cook et al 2004 ; Sugimori et al 2016 ; Martin et al 2017a ). Each of the provein stripes express distinct genes, including knirps and knirps-related in L2, abrupt in L5, and Iro-C genes in L3 and L5.…”

Modelado computacional de la autoorganización espacial generada por circuitos genéticos multicelulares

“…Aunque el resultado de este trabajo es novedoso, el uso de IFFL no es nuevo en el estudio de la embriogénesis de Drosophila. (Yorimitsu, Kiritooshi, & Nakagoshi, 2011) proporcionan pruebas de que el gen dve es un efector descendente de otd y también que la actividad de dve está involucrada en la formación del frons, una de las partes de la cápsula de la cabeza, en un bucle de alimentación incoherente de otd y dve (Sugimori, Hasegawa, & Nakagoshi, 2016). En el mecanismo de heterodimerización, por ser tan novedoso y desconocido, se introduce un término regulatorio variable de función desconocida (Fε).…”