Mitochondrial numbers and concentrations in germline cysts
| . | Mitochondrial diameter(nm)* . | . | . | . | . | . | . | . | |
|---|---|---|---|---|---|---|---|---|---|
| Stage (number of cells) . | Major axis . | Minor axis . | Number of mitochondria/cyst† . | Number of mitochondria/cell . | Cyst cytoplasmic volume (μm3) . | Cell cytoplasmic volume‡(μm3) . | Volume/mitochondrion (μm3) . | Mitochondrial volume§/cell(μm3) . | |
| Germline stem cell (10) | n.d. | n.d. | 140±32 | 140 | 1600 | 1600±520 | 0.20 | 28±12 | |
| Cystoblast (10) | n.d. | n.d. | 150±23 | 150 | 1600 | 1600±630 | 0.27 | 40±17 | |
| Two-cell cyst (16) | n.d. | n.d. | 280±46 | 140 | 2600 | 1300±110 | 0.096 | 27±17 | |
| Four-cell cyst (24) | 430±43 | 340±36 | 410±72 | 100 | 3800 | 950±130 | 0.26 | 26 | |
| Eight-cell cyst (25) | 460±30 | 380±29 | 810±31 | 100 | 4500 | 560±110 | 0.30 | 29 | |
| 16-cell cyst (25) | 550±36 | 460±34 | 1100±43 | 69 | 5800 | 360±99 | 0.53 | 36 | |
| . | Mitochondrial diameter(nm)* . | . | . | . | . | . | . | . | |
|---|---|---|---|---|---|---|---|---|---|
| Stage (number of cells) . | Major axis . | Minor axis . | Number of mitochondria/cyst† . | Number of mitochondria/cell . | Cyst cytoplasmic volume (μm3) . | Cell cytoplasmic volume‡(μm3) . | Volume/mitochondrion (μm3) . | Mitochondrial volume§/cell(μm3) . | |
| Germline stem cell (10) | n.d. | n.d. | 140±32 | 140 | 1600 | 1600±520 | 0.20 | 28±12 | |
| Cystoblast (10) | n.d. | n.d. | 150±23 | 150 | 1600 | 1600±630 | 0.27 | 40±17 | |
| Two-cell cyst (16) | n.d. | n.d. | 280±46 | 140 | 2600 | 1300±110 | 0.096 | 27±17 | |
| Four-cell cyst (24) | 430±43 | 340±36 | 410±72 | 100 | 3800 | 950±130 | 0.26 | 26 | |
| Eight-cell cyst (25) | 460±30 | 380±29 | 810±31 | 100 | 4500 | 560±110 | 0.30 | 29 | |
| 16-cell cyst (25) | 550±36 | 460±34 | 1100±43 | 69 | 5800 | 360±99 | 0.53 | 36 | |
Values without standard errors are calculated from the other data.
Mitochondrial diameters were measured by applying NIH image software to confocal images of individual mitochondria from germaria stained with ATP synthase.
Mitochondrial number was determined using ATP synthase staining and confocal microscopy.
Cell cytoplasmic volume was determined by measuring major and minor axes,as outlined by phalloidin staining, and then subtracting the nuclear volume,as determined by either the region without Vasa staining or enclosed by Lamin staining. Calculations assumed the structures were ellipsoids. The cell radii were very similar to those we measured in our transmission electron micrographs. Cyst cytoplasmic volume was determined by extrapolation for any unmeasured cells.
Mitochondrial volume was measured for germline stem cells, cystoblasts and two-cell cysts using confocal microscopy of germaria stained with ATP synthase and using NIH Image software. Total pixel volume was determined at the highest setting where labeling remained confined to mitochondria. For four-, eight-and 16-cell cysts, which contain ellipsoidal mitochondria, volume was calculated from the mitochondrial diameters.