TABLE 2.
Mutational spectrum of hprt gene mutations occurring in splenic T lymphocytes of wt mice exposed in vivo to MMS (150 mg/kg)
| Positiona (mutation) | Target sequence,b 5′→3′ | Amino acid change | No. of mutants in animal:
|
|||||
|---|---|---|---|---|---|---|---|---|
| I | II | III | IV | V | VI | |||
| Transversions | ||||||||
| 1 (AT→TA) | GTC (A) TGC | Met→Leu | 0 | 0 | 1 | 0 | 0 | 0 |
| 203 (AT→TA) | TGC (T) CAA | Leu→His | 0 | 0 | 0 | 4 | 0 | 0 |
| 40 (GC→TA) | GAT (G) AAC | Glu→stop | 0 | 0 | 0 | 0 | 0 | 1 |
| Transitions | ||||||||
| 1 (AT→GC) | GTC (A) TGC | Met→Val | 0 | 0 | 2 | 0 | 1 | 0 |
| 47 (GC→AT) | CAG (G) TTA | Gly→Asp | 1 | 0 | 0 | 0 | 0 | 0 |
| 551 (GC→AT) | TTC (C) AGA | Pro→Leu | 0 | 0 | 0 | 0 | 1 | 0 |
| Cryptic splices | Exon 9 | 0 | 0 | 0 | 0 | 0 | 5 | |
| Exon 6 | 0 | 2 | 0 | 0 | 0 | 0 | ||
| Additions | ||||||||
| 131 (triplet) | +TGG | 0 | 0 | 1 | 0 | 0 | 0 | |
| 397/398 (+G) | ATT (G) TTG | +1 Frameshift | 0 | 0 | 1 | 0 | 0 | 0 |
a
Position 1 is the first base of the start codon in the hprt coding sequence.
b
Nontranscribed strand. Bases in parentheses are sites where MMS-induced mutations were found.