Learn More
The fission yeast clade--comprising Schizosaccharomyces pombe, S. octosporus, S. cryophilus, and S. japonicus--occupies the basal branch of Ascomycete fungi and is an important model of eukaryote biology. A comparative annotation of these genomes identified a near extinction of transposons and the associated innovation of transposon-free centromeres.(More)
Structure chromosome (SMC) proteins organize the core of cohesin, condensin and Smc5-Smc6 complexes. The Smc5-Smc6 complex is required for DNA repair, as well as having another essential but enigmatic function. Here, we generated conditional mutants of SMC5 and SMC6 in budding yeast, in which the essential function was affected. We show that mutant smc5-6(More)
Some intron-containing rRNA genes of archaea encode homing-type endonucleases, which facilitate intron insertion at homologous sites in intron- alleles. These archaeal rRNA genes, in contrast to their eukaryotic counterparts, are present in single copies per cell, which precludes intron homing within one cell. However, given the highly conserved nature of(More)
Sexually reproducing organisms halve their cellular ploidy during gametogenesis by undergoing a specialized form of cell division known as meiosis. During meiosis, a single round of DNA replication is followed by two rounds of nuclear divisions (referred to as meiosis I and II). While sister kinetochores bind to microtubules emanating from opposite spindle(More)
The fission yeast Schizosaccharomyces pombe normally has haploid cells of two mating types, which differ at the chromosomal locus mat1. After two consecutive asymmetric cell divisions, only one in four 'grand-daughter' cells undergoes a 'mating-type switch', in which genetic information is transferred to mat1 from the mat2-P or mat3-M donor loci. This(More)
Mating-type switching in Schizosaccharomyces pombe involves a strand-specific, alkali-labile imprint at the mat1 (mating-type) locus. The imprint is synthesized during replication in a swi1, swi3, and polymerase alpha (swi7) dependent manner and is dependent on mat1 being replicated in a specific direction. Here we show that the direction of replication at(More)
Here, we identify a phylogenetically conserved Schizosaccharomyces pombe factor, named Rtf2, as a key requirement for efficient replication termination at the site-specific replication barrier RTS1. We show that Rtf2, a proliferating cell nuclear antigen-interacting protein, promotes termination at RTS1 by preventing replication restart; in the absence of(More)
Two archaeal introns have been discovered in the single-copy 23S rRNA-encoding gene of the hyperthermophile, Pyrobaculum organotrophum. After excision from rRNA transcripts, both introns circularize and are stably retained in the cell. Putative proteins encoded by the introns and covering most of the intron sequence share a decapeptide motif with proteins(More)
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(More)
The Swi1 and Swi3 proteins are required for mat1 imprinting and mating-type switching in Schizosaccharomyces pombe, where they mediate a pause of leading-strand replication in response to a lagging-strand signal. In addition, Swi1 has been demonstrated to be involved in the checkpoint response to stalled replication forks, as was described for the(More)