TABLE 3.
Defects in Ventral Neural Tube Gene Expression in the mind bomb Mutant Hindbraina
| Defect in Expression Pattern
|
||||
|---|---|---|---|---|
| Gene | Genotype | |||
| No Defects | Gap in r2/r3 | Gap in r4 | ||
| shh (25 hpf) | Wild-type (20) | 20/20 | 0/20 | 0/20 |
| Mutant (14) | 6/14 | 2/14 | 6/14 | |
| nk2.2 (24 hpf) | Wild-type (20) | 20/20 | 0/20 | 0/20 |
| Mutant (24) | 6/24 | 1/24 | 17/24 | |
| net1b (30 hpf) | Wild-type (20) | 20/20 | 0/20 | 0/20 |
| Mutant (52) | 16/52 | 0/52 | 36/52 | |
a
Number of embryos are shown in parentheses. Gaps in rhombomeres 2, 3, and 4 (r2, r3, r4) were scored, while gaps in the caudal hindbrain, which were infrequent, and other defects in expression pattern were excluded from analysis. The position of the gap in expression was determined relative to the outlines of the otic vesicle, which spans rhombomeres 4–6 at the developmental stages examined. hpf, hours postfertilization.