Analysis of extracellular matrix composition in the visceral muscles of Nidogen mutant larvae in Drosophila

Nidogen in development and disease

“…Studies in Drosophila indicate that Laminin is crucial for the incorporation of Nidogen into the BM in embryos, fat body and the egg chamber ( Dai et al, 2018 ; Wolfstetter et al, 2019 ; Töpfer et al, 2022 ). Interestingly, although Nidogen requires Laminin for recruitment, studies in Drosophila , C. elegans and mice show that Collagen IV and Perlecan are capable of assembling independently of Nidogen into the BM ( Kang and Kramer, 2000 ; Bader et al, 2005 ; Dai et al, 2018 ; Wolfstetter et al, 2019 ; Töpfer and Holz, 2020 ; Töpfer et al, 2022 ). Thus, the ex vivo experiments, which identified stable ternary complexes that depend on Nidogen, are not required for the overall architecture of the BM in vivo .…”

Basement membrane dynamics and mechanics in tissue morphogenesis

“…Essential for incorporation is the interaction of the G3 domain with the Laminin γ-subunit, while the G2 domain allows linkage to Perlecan and Collagen IV ( Fox et al, 1991 ; Hopf et al, 2001 ; Mann et al, 1989 ; Reinhardt et al, 1993 ). Studies in Drosophila , C. elegans , and mice have shown Nidogen is dispensable for assembly of the other core components ( Bader et al, 2005 ; Dai et al, 2018 ; Kang and Kramer, 2000 ; Töpfer and Holz, 2020 ; Wolfstetter et al, 2019 ). Notably, all studies show a role of Nidogen in BM stability and tissue integrity ( Fig.…”

Epithelial Cell Polarity During Drosophila Midgut Development

“…During the past 20 years, Drosophila midgut has proven an exciting model system to study epithelial homeostasis, since (Wolfstetter and Holz, 2012;Lin et al, 2013;You et al, 2014;Pert et al, 2015;Töpfer and Holz, 2020;Pitsidianaki et al, 2021) Wing (Micchelli and Perrimon, 2006;Ohlstein and Spradling, 2006;Lucchetta and Ohlstein, 2012;Zeng et al, 2013;Antonello et al, 2015;He et al, 2018;Miguel-Aliaga et al, 2018;Reiff and Antonello, 2019;Rojas Villa et al, 2019;Jasper, 2020). The ISCs reside beneath the tri-cellular SJs between ECs, and do not contact the gut lumen or have an apical brush border, forming only AJs with their neighbours (Shanbhag and Tripathi, 2009;Xu et al, 2018;Chen and St Johnston, 2022).…”

“…The ECM is assembled into a sheet-like basement membrane (BM) between the epithelium and the visceral muscle layers ( Shanbhag and Tripathi, 2009 ). All four main types of the basement membrane components are present: type IV collagen (α1 2 α2 heterotrimers with Col4a1 as the α1 subunit and Vkg as the α2 subunit), Laminins (αβγ-heterotrimers with LanA and Wb as α subunits, LanB1 as the β subunit and LanB2 as the γ subunit), Nidogen and Perlecan ( Table 1 ) ( Broadie et al, 2011 ; Davis et al, 2019 ; Töpfer and Holz, 2020 ). Laminins and Type IV collagen form independent mesh-like structures with the Laminins closer to the epithelial cells.…”

“…At this stage, haemocytes (migrating macrophages) are the only source of secreted type IV collagen and Perlecan ( Matsubayashi et al, 2017 ) and they do not reach the endoderm until after the migration is complete ( Urbano et al, 2011 ; Pitsidianaki et al, 2021 ). Nidogen is reported to have similar expression pattern to LanB1 during embryogenesis but is not required for endoderm migration or formation ( Urbano et al, 2009 ; Dai et al, 2018 ; Töpfer and Holz, 2020 ). At stage 16, Laminins, Collagens, Nidogen, and Perlecan, as well as other mature ECM components, such as MDP-1 and SPARC are all found in between the endoderm and mesoderm, forming a more complex ECM network ( Wolfstetter and Holz, 2012 ).…”