Automated multidimensional image analysis reveals a role for Abl in embryonic wound repair

Abstract

The embryonic epidermis displays a remarkable ability to repair wounds rapidly. Embryonic wound repair is driven by the evolutionary conserved redistribution of cytoskeletal and junctional proteins around the wound. Drosophila has emerged as a model to screen for factors implicated in wound closure. However, genetic screens have been limited by the use of manual analysis methods. We introduce MEDUSA, a novel image-analysis tool for the automated quantification of multicellular and molecular dynamics from timelapse confocal microscopy data. We validate MEDUSA by quantifying wound closure in Drosophila embryos, and we show that the results of our automated analysis are comparable to analysis by manual delineation and tracking of the wounds, while significantly reducing the processing time. We demonstrate that MEDUSA can also be applied to the investigation of cellular behaviors in three and four dimensions. Using MEDUSA, we find that the conserved nonreceptor tyrosine kinase Abelson (Abl) contributes to rapid embryonic wound closure. We demonstrate that Abl plays a role in the organization of filamentous actin and the redistribution of the junctional protein β-catenin at the wound margin during embryonic wound repair. Finally, we discuss different models for the role of Abl in the regulation of actin architecture and adhesion dynamics at the wound margin.

The Crk adapter protein is essential forDrosophilaembryogenesis, where it regulates multiple actin-dependent morphogenic events

“…4.4 ± 0.5 hr 1 , respectively) (mean ± SEM). Consistent with this, when we previously measured the rate of closure during the fast phase of wound repair in abl maternal/zygotic mutants, it was 37% slower than in wildtype embryos (Zulueta-Coarasa et al, 2014). Thus, wound closure provides another example of a morphogenetic process requiring both Abl and Crk.…”

“…This process is tightly coordinated with dynamic changes in cell-cell adhesion (reviewed in Hunter and Fernandez-Gonzalez, 2017). Abl is required for efficient wound closure, via effects on the organization of filamentous actin and the reorganization of cell-cell junctions at the wound margin (Zulueta-Coarasa et al, 2014).…”

“…Our analysis revealed that Crk knockdown slows wound healing. Intriguingly, Abl loss has a similar effect, and in the case of Abl its loss impairs both actin organization at the wound edge and enrichment of the cadherin-catenin complex at tricellular junctions (Zulueta-Coarasa et al, 2014). SCAR is also critical for embryonic wound healing (Matsubayashi et al, 2015).…”

Endocytosis-dependent coordination of multiple actin regulators is required for wound healing

“…The AJs along the wound edge undergo changes in composition and appearance after wounding, and this remodeling has been proposed to be important in triggering wound responses (Pickering et al, 2013;Carvalho et al, 2014;Tsarouhas et al, 2014;Zulueta-Coarasa The ability to heal wounds efficiently is essential for life. After wounding of an epithelium, the cells bordering the wound form dynamic actin protrusions and/or a contractile actomyosin cable, and these actin structures drive wound closure.…”

Quantitative analysis of cell shape and the cytoskeleton in developmental biology

“…The automated tracing algorithm, MEDUSA, employs an active contour algorithm where the delineation of the wound evolves to minimize its energy (green). (Reprinted with permission from Zulueta‐Coarasa, Tamada, Lee, & Fernandez‐Gonzalez (). Copyright 2014 The Company of Biologists) (b) Pavement cells in Arabidopsis thaliana exhibit complex shapes.…”