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Figure 1. Surgical configuration for observing developing pupal wing tissues in vivo.For the complete developmental process over time, refer to Movie S1. (a) A pupa immediately after the operation of curling up the pupal forewing. The exposed hindwing is boxed. (b) The exposed hindwing from (a), with identification of the compartments. (c) A pupa immediately before eclosion with fully developed color patterns on the hindwing. Note that the ventral forewing also display a fully developed color pattern in this individual. This individual is identical to that shown in (a). (d) The hindwing of (c), with identification of the compartments, which can be compared to (b). Note that compartment CuA1 exhibits a large eyespot.
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Figure 2. The changes in the pupal wing tissue in the first two days.The hours indicate real developmental time (i.e., the postpupation time), and the minutes and seconds in parentheses indicate time points in the playing movies. (a) Whole-wing bright-field images. The transparent tissue is becoming gray-white. Also refer to Movie S1. (b) Bright-field images of compartment CuA1. The small boxed areas are enlarged in the adjacent large boxes. The elaboration and movement of the tracheal branches are notable. Regular arrays of epithelial cells are observed by 48 h postpupation. The possible appression front moving from the basal to the distal region is indicated by green arrows. White arrows indicate the major tracheae that run off the wing edge at the early stage. Also refer to Movie S2. (c) Autofluorescent images of compartment CuA1 under blue light. Blue arrows indicate the bordering lacuna, which corresponds to the wing edge. White arrows indicate the major tracheae that run off the wing edge at the early stage. The pink arrows indicate the marginal focus (edge spot), which is the possible organizing center for the marginal band system. The yellow arrows indicate the location of the organizing center for a border symmetry system including an eyespot. The extension of tracheal branches, especially toward the organizing centers, is detectable. Moving hemocytes are observed in a relatively early stage, some of which are most likely macrophages. In the later stages, hemocytes are confined to the bordering lacuna, which may promote degradation of the peripheral tissue. Also refer to Movie S3.
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Figure 3. Array and scale formation.Also refer to Movie S4. (a) The hindwing basal region after the curling operation. The magnified area of compartment Sc+R1 in the subsequent panels is boxed. (b-f) Cellular changes over time. The small boxed areas are enlarged in the adjacent large boxes. Transparent non-aligned epithelial cells are observed in the early stage in (b). Vigorously moving tracheal branches are notable in (c), together with moving hemocytes, some of which are most likely macrophages. Later, the epithelial cells are regularly arranged, and scales grow, as shown in (d) and (e), which are seen as white objects that are increasing in size. Scale growth accompanies the increase in wing area in (f), which appears to be driven by the contraction pulses of the wing tissue. Red arrowheads indicate single cells or scales that are circled with dots. All panels (b-f) are shown at the same magnification.
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Figure 4. Behavior of tracheal branches and hemocytes.(a, b) Bright-field image of compartment CuA1 immediately after pupation (0 h postpupation). The boxed region is magnified in (b). Many tracheal branches are already observed at this point, but they are most likely immature and cannot be seen clearly under our observation conditions. They also do not move vigorously. (c, d) The identical CuA1 region 23 h postpupation. Many tracheal branches are observed as white crinoid-like objects, with one side attached to the major trachea. They move relatively vigorously. A single branch exhibits a white knob, from which many thin branches (i.e., tracheoles) radiate. Also note the free-moving hemocytes (indicated by a red arrowhead). (e-g) Tracheal branches in compartment Sc+R1. The boxed region in (e) is magnified in (f), and the boxed region in (f) is further magnified in (g), showing the dynamics of the branch, knob, and tracheoles. The red arrowheads in (g) indicate the identical position in the images over time. The postpupation time is indicated in (g).
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Figure 5. Fluorescent images of array and scale formation.Wing tissue was stained with CFSE. (a) Stained M3 and CuA1 compartments. Compartment CuA1 exhibits an organizing center, indicated by a yellow arrowhead. The organizing center appears to be resistant to staining. Note that the adjacent M3 compartment does not have this non-stained black area, probably because the M3 compartment does not have an eyespot in adult wings. Also see Figure 6a. Red arrows indicate the major tracheae. The boxed region is enlarged in the subsequent panels. Also refer to Movie S5. (b) Cellular changes over time. At 6 h, the cellular density appears to decrease, and by 16 h the tissue is occupied by densely packed epithelial cells. After 24 h, the cells gradually become arranged, and the wing area increases, which appears to be driven by the contraction pulses that become frequent after 30 h. Scale growth is observed immediately after the cellular row arrangement occurs. All panels are shown at the same magnification.
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Figure 6. Fluorescent images of epithelial cells and tracheal branches.(a) Low-magnification image of compartments CuA1 and M3 stained with MitoTracker Orange for mitochondria (in red) and SYBR Green-1 for nuclei (in green), immediately after pupation. The red arrowhead indicates the organizing center for the border symmetry system, which is resistant to staining. This non-stained black area was not detected in the adjacent compartment where no eyespot exists in adult wings. Also see Figure 5a. The boxed region is magnified in (b). (b) High-magnification image of the epithelial cells boxed in (a). Yellow dots indicate mitochondrial DNA. (c) Optical cross section of the stained epithelial cells. The diameter of a single cell is indicated by a double-headed arrow. Cellular nucleus is encircled by red dots. Note the mitochondrial distribution on the dorsal surface of the cell. Yellow regions indicate mitochondrial DNA. (d, e) Compartment CuA1 stained with DiBAC4(3). Tracheae are stained well, and the epithelial cells are weakly stained. A portion of a tracheal knob is indicated by red arrowheads to demonstrate its vigorous movement.
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Figure 7. Areal changes associated with the wing-tissue contraction pulses.(a) Bright-field images of the hindwing over time. The postpupation time is indicated in each panel. The areas of the three different compartments (M1, M2, and CuA1), encircled with red, blue, and yellow dotted lines, were measured and normalized according to the hindwing span indicated by the double-headed blue arrow. Note that the hindwing is most contracted at 51â¶14 h and at 52â¶19 h postpupation. These are static images from Movie S1. (b) Relative areal changes over time in compartments M1, M2, and CuA1. The time points correspond to the images shown in (a). These measurements were performed using Movie S1. (c) Summation of the three compartment areas.
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Figure 8. Distance changes associated with the wing-tissue contraction pulses and autofluorescence intensity.(a) Three distance measurements (red, blue, and yellow double-headed arrows, designated 1, 2, and 3, respectively) between the two veins that define compartment CuA1. The postpupation time is also indicated. All panels are shown at the same magnification. These are static images from Movie S3. (b) Changes in length (distance) between the two wing veins over time. The measured distances are indicated in (a). These measurements were conducted using Movie S3. (c, d) Images of the distances between the wing veins at 0 h and 80 h postpupation in compartment CuA1. These panels are at the same magnification, showing static images from Movie S6. These images of the wing of a physically fixed pupa were taken at the same position at different time points, and the distances were measured between the two points despite the tilting of the wing veins relative to the double-headed red arrows as the wing grows. (e) Relative distance between the wing veins in compartment CuA1, as shown in (c, d) (indicated with red dots and lines), and the contraction frequency (shown in blue dots and lines). The distance at 0 h was considered to be 1.00, and other values were normalized accordingly. The broken lines indicate difficulty in measuring the distance, but no change appeared to occur afterwards. Note that an increase of the contraction frequency is followed by an increase in this distance in the early phase, and a decrease of the beat frequency is followed by the distance plateauing. These measurements were conducted using images from Movie S6. (f) The relative distance between the wing veins, as shown in (e) (measured from Movie S6), and the autofluorescence intensity (measured from Movie S3). The autofluorescence intensity increases together with the relative length between the wing veins.
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Figure 9. Ontogeny of the pigment deposition process at the whole-wing level.Real time points are shown along with the playing time points from Movie S1 (in parentheses). (a) Changes in the whole wing. The background black coloration emerges at the center of the wing (indicated by an arrow at 150 h). (b) High-magnification images of the eyespot. The red ring is produced first, and the black ring is produced at a single location at 150 h (indicated by an arrow). The black ring then develops around the red ring. Later, the width of the black ring expands considerably.
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Figure 10. Ontogeny of the pigment deposition process at the compartmental level.Real time points are shown along with the playing time points from Movie S6 (in parentheses). (a) The changes in CuA1 and its adjacent compartments. (b) High-magnification images of CuA1 compartment. The eyespot red ring develops first. A possible red fragment is indicated by a black asterisk at 130 h. Black fragments are indicated by white asterisks at 136 h. Black and red arrows indicate artifactual objects that can be used as physical reference points. Reference point R is located in the middle of the red ring at 135 h but is gradually invaded by the black ring. Reference point B is located far from the black ring at 136 h, but the black ring reaches it at 139 h. The directions of black ring expansion are indicated by double-headed white arrows in the image from 139 h. (c) Another high-magnification image. Reference point B is located far from the black fragment (indicated by a white asterisk) at 135 h, but the black region reaches it at 139 h. Reference point P is located far from the black region at the center of the prospective parafocal element (indicated by a yellow asterisk), but the black region later expands laterally to cover the reference point P entirely. The directions of expansion of the black pigment are indicated by white arrows in the image from 139 h.
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