KEM1 — Schizosaccharomyces pombe 972h-

Summary

SPAC17A5.14 (KEM1, also known as exo2 or SpXRN1) on chromosome 1 of Schizosaccharomyces pombe encodes a 5'-3' exoribonuclease with 5' nucleotidase, recombinase, and RNA nuclease activities, and binds RNA, rRNA, microtubules, and magnesium and zinc ions. The gene is associated with NAD-cap decapping, nonsense-mediated mRNA decay, nuclear mRNA surveillance, rRNA breakdown, tRNA decay, sno(s)RNA processing, and termination of RNA polymerase II transcription. It is linked to the Las1 complex, P-bodies, stress granules, and the perinuclear cytoplasm. Phenotypically, KEM1 is associated with absent meiosis, decreased lifespan, increased necrotic cell death, delayed vegetative growth, increased anaerobic growth, increased gamma ray resistance, and abnormal nuclear fusion during mating. Studies of related genes in other species link the family to rapid tRNA decay and reduced virulence.