swi1 and swi3 perform imprinting, pausing, and termination of DNA replication in S. pombe.
The developmental program of cell-type switching of S. pombe requires a strand-specific imprinting event at the mating-type locus (mat1). Imprinting occurs only when mat1 is replicated in a specific direction and requires several trans-acting factors. This work shows (1) that the factors swi1p and swi3p act by pausing the replication fork at the imprinting site; and (2) that swi1p and swi3p are involved in termination at the mat1-proximal polar-terminator of replication (RTS1). A genetic screen to identify termination factors identified an allele that separated pausing/imprinting and termination functions of swip. These results suggest that swi1p and swi3p promote imprinting in novel ways both by pausing replication at mat1 and by terminating replication at RTS1.
Dalgaard
J Z
JZ
DHHS, NCI, Division of Basic Sciences Gene Regulation and Chromosome Biology Laboratory, NCI-Frederick Cancer Research and Development Center, Maryland 21702, USA.
Klar
A J
AJ
D018797:Cell Cycle Proteins; D004261:DNA Replication / Q000502:physiology*; D004264:DNA Topoisomerases, Type I / Q000235:genetics; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics*; D005820:Genetic Testing; D018392:Genomic Imprinting / Q000502:physiology*; D020125:Mutation, Missense / Q000502:physiology; D009363:Neoplasm Proteins / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics*; D018741:Replication Origin / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D012568:Schizosaccharomyces; D029702:Schizosaccharomyces pombe Proteins; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics*
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; C072981:SWI3 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C513096:swi1 protein, S pombe; D004264:DNA Topoisomerases, Type I