Egfr signalling defines a protective function for ommatidial orientation in the<i>Drosophila</i>eye

Brown, Katherine; Freeman, Matthew

doi:10.1242/dev.00773

Cited by 58 publications

(81 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the eye, Fz/PCP signaling, together with the Notch pathway, is responsible for R3/R4 fate induction and thus for the establishment of ommatidial chirality (Cooper and Bray, 1999;Fanto and Mlodzik, 1999;Tomlinson and Struhl, 1999). Besides, it has been shown that the ommatidial rotation, depends on the Egfr pathway (Brown and Freeman, 2003;Gaengel and Mlodzik, 2003;Strutt and Strutt, 2003). Moreover, downstream of Egfr there is a requirement for the Ras/MAPK cascade and Canoe, an adherensjunction-associated protein (Young et al, 1993), that provides a link from Egfr to cytoskeletal elements (Gaengel and Mlodzik, 2003).…”

Section: Introductionmentioning

confidence: 99%

Analysis of the role of the Rac/Cdc42 GTPases during planar cell polarity generation in Drosophila

Muñoz-Descalzo

Gómez-Cabrero²,

Mlodzik³

et al. 2007

Int. J. Dev. Biol.

View full text Add to dashboard Cite

Initial genetic studies in Drosophila suggested that several members of the Rho subfamily (RhoA, Rac1 and Cdc42) are involved in planar cell polarity (PCP) establishment. However, analyses of Rac1, Rac2 and Mtl loss-of-function (LOF) mutants have argued against their role in this process. Here, we investigate in detail the role of the Rho GTPases Mtl, Cdc42, Rac1 and Rac2 in PCP generation. These functional analyses were performed by overexpressing Mtl in eyes and wings, by performing genetic interaction assays and by using a combination of triple and quadruple mutant LOF clones. We found that Mtl overexpression caused PCP phenotypes and that it interacted genetically with other Rho GTPases, such as Rac1 and Cdc42 as well as with several PCP genes, such as stbm, pk and aos. However, Mtl was not found to interact with Rac2, RhoA and other members of the Fz/PCP pathway. Triple mutant clones of Rac1, Rac2 and Mtl were found to exhibit mild PCP defects which were enhanced by reduction of Cdc42 function with a hypomorphic Cdc42 allele. Taken together, these and previous results suggest that Rho GTPases may have partially overlapping functions during PCP generation. Alternatively, it is also possible that the mild PCP phenotypes observed could indicate that they are required at low levels in that process. However, since not all of them function upstream of a JNK cassette, we propose that they may act in at least two parallel pathways.

show abstract

Section: Introductionmentioning

confidence: 99%

Analysis of the role of the Rac/Cdc42 GTPases during planar cell polarity generation in Drosophila

Muñoz-Descalzo

Gómez-Cabrero²,

Mlodzik³

et al. 2007

Int. J. Dev. Biol.

View full text Add to dashboard Cite

show abstract

“…Egfr signaling promotes rotation via the Ras/Cno and Ras/Mapk/Pnt effectors (Brown and Freeman, 2003;Gaengel and Mlodzik, 2003), so its output must be dampened to slow rotation. Ed binds and inhibits the Egf receptor (Bai et al, 2001;Rawlins et al, 2003;Spencer and Cagan, 2003), whereas Fred binds Ed and interferes with this inhibition (S.A.S., unpublished).…”

Section: Research Articlementioning

confidence: 99%

“…Although mosaic analyses indicate a requirement for the PCP genes in specifying the R3 and R4 cell fates and additional work demonstrates a tight link between fate specification and the direction of rotation, the mechanisms that control the degree to which ommatidia rotate are poorly understood (Fanto and Mlodzik, 1999;Strutt et al, 2002;Wolff and Rubin, 1998). The identification of several proteins that affect only the degree of rotation, including the serine/threonine kinase Nemo (Nmo), Ecadherin (Shotgun -FlyBase), N-cadherin and members of the Egfr signaling pathway (Brown and Freeman, 2003;Choi and Benzer, 1994;Fiehler and Wolff, 2008;Gaengel and Mlodzik, 2003;Mirkovic and Mlodzik, 2006;Strutt and Strutt, 2003), suggests that a subset of genes might act to regulate this event.…”

Section: Introductionmentioning

confidence: 99%

“…Genetic evidence has revealed that the Egfr signaling pathway promotes rotation (Mirkovic and Mlodzik, 2006), even though ommatidia in Egfr pathway mutant eyes can over-or under-rotate, leading to a wide variance in the degree to which individual ommatidia rotate (Brown and Freeman, 2003;Gaengel and Mlodzik, 2003;Strutt and Strutt, 2003). Egfr pathway members signal through both the Mapk/Pnt transcriptional cascade and Canoe (Cno), the fly homolog of Afadin/AF-6 (Brown and Freeman, 2003;Gaengel and Mlodzik, 2003).…”

Section: Introductionmentioning

confidence: 99%

“…Egfr pathway members signal through both the Mapk/Pnt transcriptional cascade and Canoe (Cno), the fly homolog of Afadin/AF-6 (Brown and Freeman, 2003;Gaengel and Mlodzik, 2003). Egfr pathway members also interact genetically with E-cadherin and N-cadherin during rotation (Mirkovic and Mlodzik, 2006).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The cell adhesion molecules Echinoid and Friend of Echinoid coordinate cell adhesion and cell signaling to regulate the fidelity of ommatidial rotation in theDrosophilaeye

2009

View full text Add to dashboard Cite

Directed cellular movements are a universal feature of morphogenesis in multicellular organisms. Differential adhesion between the stationary and motile cells promotes these cellular movements to effect spatial patterning of cells. A prominent feature of Drosophila eye development is the 90°rotational movement of the multicellular ommatidial precursors within a matrix of stationary cells. We demonstrate that the cell adhesion molecules Echinoid (Ed) and Friend of Echinoid (Fred) act throughout ommatidial rotation to modulate the degree of ommatidial precursor movement. We propose that differential levels of Ed and Fred between stationary and rotating cells at the initiation of rotation create a permissive environment for cell movement, and that uniform levels in these two populations later contribute to stopping the movement. Based on genetic data, we propose that ed and fred impart a second, independent, 'brake-like' contribution to this process via Egfr signaling. Ed and Fred are localized in largely distinct and dynamic patterns throughout rotation. However, ed and fred are required in only a subset of cells -photoreceptors R1, R7 and R6 -for normal rotation, cells that have only recently been linked to a role in planar cell polarity (PCP). This work also provides the first demonstration of a requirement for cone cells in the ommatidial rotation aspect of PCP. ed and fred also genetically interact with the PCP genes, but affect only the degree-of-rotation aspect of the PCP phenotype. Significantly, we demonstrate that at least one PCP protein, Stbm, is required in R7 to control the degree of ommatidial rotation.

show abstract

A new allele uncovers the role of echinus in the control of ommatidial rotation in the Drosophila eye

Montrasio

Mlodzik

Fanto

2007

Developmental Dynamics

View full text Add to dashboard Cite

The precise orientation of the ommatidia in the Drosophila eye is achieved through a specialized process of cell migration taking place in the third-instar eye imaginal disc when ommatidial clusters rotate by 90 degrees. This process is strictly coordinated with the establishment of planar cell polarity (PCP), but it relies on a specific set of genes that control its mechanism independently from PCP signaling. Recently, the epidermal growth factor receptor (EGFR) pathway has been implicated in determining ommatidial rotation. We have isolated a new allele of echinus, a gene known to control the patterning and number of interommatidial cells. We show that echinus displays defects in the rotation of ommatidia that are not evident until mid-pupal stages, and we propose that echinus action is that of opposing EGFR by an unknown mechanism and that this can explain both its influence in ommatidial rotation and lattice programmed cell death (PCD). Developmental Dynamics 236:2936 -2942, 2007.

show abstract

Egfr signalling defines a protective function for ommatidial orientation in theDrosophilaeye

Cited by 58 publications

References 62 publications

Analysis of the role of the Rac/Cdc42 GTPases during planar cell polarity generation in Drosophila

Analysis of the role of the Rac/Cdc42 GTPases during planar cell polarity generation in Drosophila

The cell adhesion molecules Echinoid and Friend of Echinoid coordinate cell adhesion and cell signaling to regulate the fidelity of ommatidial rotation in theDrosophilaeye

A new allele uncovers the role of echinus in the control of ommatidial rotation in the Drosophila eye

Contact Info

Product

Resources

About