Requirement of sequences outside the conserved kinase domain of fission yeast Rad3p for checkpoint control.
The fission yeast Rad3p checkpoint protein is a member of the phosphatidylinositol 3-kinase-related family of protein kinases, which includes human ATMp. Mutation of the ATM gene is responsible for the disease ataxia-telangiectasia. The kinase domain of Rad3p has previously been shown to be essential for function. Here, we show that although this domain is necessary, it is not sufficient, because the isolated kinase domain does not have kinase activity in vitro and cannot complement a rad3 deletion strain. Using dominant negative alleles of rad3, we have identified two sites N-terminal to the conserved kinase domain that are essential for Rad3p function. One of these sites is the putative leucine zipper, which is conserved in other phosphatidylinositol 3-kinase-related family members. The other is a novel motif, which may also mediate Rad3p protein-protein interactions.
Chapman
C R
CR
Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
Evans
S T
ST
Carr
A M
AM
Enoch
T
T
D000730:Androstadienes / Q000494:pharmacology; D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins; D002470:Cell Survival / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D017124:Conserved Sequence; D004261:DNA Replication / Q000235:genetics; D004268:DNA-Binding Proteins; D005786:Gene Expression Regulation; D005800:Genes, Fungal; D018816:Genes, cdc; D005816:Genetic Complementation Test; D006918:Hydroxyurea / Q000494:pharmacology; D016350:Leucine Zippers / Q000235:genetics; D008938:Mitosis / Q000235:genetics; D009154:Mutation; D009838:Oligodeoxyribonucleotides; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics* / Q000378:metabolism; D010957:Plasmids; D017346:Protein Serine-Threonine Kinases; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D025521:Tumor Suppressor Proteins; D014466:Ultraviolet Rays / Q000009:adverse effects; D000077191:Wortmannin; D015003:Yeasts
D000730:Androstadienes; D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D006918:Hydroxyurea; D009838:Oligodeoxyribonucleotides; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011506:Proteins; D025521:Tumor Suppressor Proteins; D000077191:Wortmannin; C576324:ATM protein, human