Skip to main content
Figure 4 | Frontiers in Zoology

Figure 4

From: Development and epithelial organisation of muscle cells in the sea anemone Nematostella vectensis

Figure 4

Epithelial organization of the columnar muscles. All sections are cross-sections A Overview of the retractor muscle region. B Overview of the parietal muscle region. C Detail of B. A distinct neural plexus consisting of numerous neurites is located next to the parietal muscle and close to the transition zone to the ring muscle. Inlet 1: spot-like adherens junctions between the basal part (black arrow) connect muscle cells to each other. Focal adhesions (white arrow) connect the cells to the mesoglea. Inlet 2: Detail image of neurites containing neural vesicles (white arrow). D Detail of B. Parietal muscle cells consist of a cell body involved in building up the epithelium. Via cytoplasmic bridges they are connected to the myofilament-containing basal part of the cell, adjacent to the mesoglea (cell highlighted in yellow); this yields a consistent sheet of myonemes. E and F Details of A. Muscle cells (highlighted in yellow) remain epithelial at least in the proximal and distal boundaries of the retractor muscle. E (inlet): Focal adhesion between muscle cell and mesoglea. G Detailed image of well-formed myonemes in the central region of the retractor muscle. Thin cytoplasmic bridges (inlet, black arrow) are projected by every cell. Basal parts of the cells are connected by spot-like adherens junctions (black arrows). H Detailed image of a ring muscle cell showing its participation in building up the epithelium. The myofilaments are located at the basal part of the cell. cb, cytoplasmic bridges; gc, gastric cavity; gd, gastrodermis; m, mitochondrium; mg, mesoglea; myo, myoneme; np, neural plexus; nu, nucleus; pam, parietal muscle; rim, ring muscle. Scale: A, B: 20 μm, C-F, H: 5 μm, G: 2 μm.

Back to article page