A Survey of New Temperature-Sensitive, Embryonic-Lethal Mutations in C. elegans: 24 Alleles of Thirteen Genes
Figure 3
A. DIC time-lapse images of wild-type and rsa-1(or598 ts) embryos. In the rsa-1 mutant the nuclear centrosomal complex (NCC) failed to rotate and a small transverse P0 spindle assembled, cytokinesis failed, and multiple nuclei were present at the two cell equivilent stage. The rsa-1(or598 ts) embryo was shifted to the restrictive temperature for∼1 min. prior to imaging. Black dots represent centrosomes/ spindle poles and asterisks denote multiple nuclei per cell at the two cell stage. Times in min:sec are given relative to NEBD. Scale bar, 10 µm. B. Amino acid alteration in the mutant. Asterisk indicates the changed residue. Homologous proteins are aligned below the C. elegans protein. C. Defect map for individual embryos observed during time-lapse recordings: embryos are listed on the left and phenotypes are listed on the top: 1; pronuclei meet prior to NEBD, 2; Nuclear centrosomal complex centration, 3; Nuclear centrosomal complex rotation, 4; spindle size, 5; successful cytokinesis, 6; one nucleus per cell at two cell stage. In the long upshifts, hermaphrodites were transferred to the restrictive temperature for 5–8 hours. In the short upshifts, embryos were harvested from hermaphrodites grown at 15°C and immediately mounted on agar pads for imaging, which took ∼1 min.