Higher order chromosome structure is affected by cold-sensitive mutations in a Schizosaccharomyces pombe gene crm1+ which encodes a 115-kD protein preferentially localized in the nucleus and its periphery.

摘要: We isolated a novel class of Schizosaccharomyces pombe cold-sensitive mutants with deformed nuclear chromosome domains consisting thread- or rodlike condensed segments at restrictive temperature. Their mutations were mapped in novel, identical locus designated crm1 (chromosomal region maintenance). The also show the following phenotypes. DNA, RNA, and protein syntheses diminish At permissive temperature, amount one particular protein, p25, greatly increases. mutant growth is hypersensitive to Ca2+ resistant kinase inhibitors. cloned 4.1-kb-long crm1+ gene that rescued above phenotypes by transformation determined its nucleotide sequence, which predicts 1,077-residue protein. Affinity-purified antiserum raised against polypeptide expressed Escherichia coli detected 115-kD S. extracts. Genomic Southern hybridization immunoblotting suggested product might be highly conserved distant organisms. Through immunofluorescence microscopy, appeared principally localized within nucleus periphery. speculate those components modify structures regulate environment required for maintaining higher order structures.