Department of Biochemistry, New York University School
of Medicine, 550 First Avenue, New York,
New York 10016, USA. hannah.klein@med.nyu.edu
The Saccharomyces cerevisiae gene SGS1 encodes a protein
related to the human DNA helicases defective in Werner syndrome, Bloom syndrome
and Rothmund-Thomson syndrome. Yeast cells lacking the Sgs1 helicase and a
related helicase, Srs2, are inviable or grow extremely poorly. The growth
defect can be rescued by crippling the homologous recombination repair pathway,
indicating that the essential function of these genes is related to recombination
