Skip to main content
Figure 6 | BMC Developmental Biology

Figure 6

From: Distinct functions of the laminin β LN domain and collagen IV during cardiac extracellular matrix formation and stabilization of alary muscle attachments revealed by EMS mutagenesis in Drosophila

Figure 6

Analysis of cardiomyocyte arrangement and polarity. (A-E) Dorsal views of stage 17 embryos stained with antibodies against Mef2 and Slit as indicated. (A) Normal arrangement of cardiomyocytes in two rows with Slit localization predominantly at the luminal side. In homozygous LanB1S0733(B) and hemizygous LanB1S0733/Df(2L)ED12527 (C) embryos cardiomyocytes are arranged more densely, but mostly still with normal polarity. Small gaps and stretches with alignment defects are observed leading to occasional interruptions (arrowheads) or mislocalization of Slit (arrow) at these positions. (D) In Cg25CS3064 and in Cg25CS3064/Df(2L)Exel7022 (E) embryos cardiomyocytes align essentially as in wild type with normal luminal Slit localization except for a slightly weaker Slit concentration in the posterior heart portion. Minor cardioblast misalignments in the posterior heart are observed only in Cg25CS3064 homozygotes. (F-H) Stage 17 embryos with a Hand-GFP transgene to visualize cardiomyocytes and PCs, co-stained with antibodies against Dystroglycan (Dg). YZ plane cross-sections are shown below each XY projection at the indicated positions. (F) Heterozygous Cg25C embryos as identified by the presence of balancer encoded twi-GAL4/UAS-GFP fluorescence showing normal Dg localization at the luminal and outer membrane domains of cardiomyocytes. A large lumen is formed in the ventricle (F3, F4) and a narrower one in the aorta (F1, F2). (G) Dorsal vessel of a LanB1S0733 embryo with interrupted heart cell alignment and discontinuous Dg staining especially at its outer surface and in the ventricular portion. Along the anterior-posterior axis sections containing no lumen or a small lumen are present (G1-4). (H, H1-4) Embryo with the homozygous G552D mutation in the Cg25CS3064/Cg25CDTS-L3 background shows normal Dg localization and lumen formation.

Back to article page