No prospore membranes are formed in a
spo21Δ mutant. Strains AN120
(SPO21/SPO21) and AN180
(spo21Δ/spo21Δ) were transferred to
2% KOAc and analyzed by indirect immunofluorescence as described in
MATERIALS AND METHODS. (A, E, and I) AN120 stained with anti-Ssop,
anti-Sncp, and anti-Spr3p antibodies, respectively. (B, F, and J) DAPI
staining of the corresponding cells in A, E, and I. (C, G, and K) AN180
stained with anti-Ssop, anti-Sncp, and anti-Spr3p antibodies,
respectively. (D, H, and L) DAPI staining of the corresponding cells in
C, G, and K, demonstrating that the cells analyzed have undergone
meiosis II. Images in E, F, G, H, K, and L are composites.