The DNA helicase activity of BLM is necessary for the correction of the genomic instability of bloom syndrome cells
Molecular biology of the cell, 1999•Am Soc Cell Biol
Bloom syndrome (BS) is a rare autosomal recessive disorder characterized by growth
deficiency, immunodeficiency, genomic instability, and the early development of cancers of
many types. BLM, the protein encoded by BLM, the gene mutated in BS, is localized in
nuclear foci and absent from BS cells. BLM encodes a DNA helicase, and proteins from
three missense alleles lack displacement activity. BLM transfected into BS cells reduces the
frequency of sister chromatid exchanges and restores BLM in the nucleus. Missense alleles …
deficiency, immunodeficiency, genomic instability, and the early development of cancers of
many types. BLM, the protein encoded by BLM, the gene mutated in BS, is localized in
nuclear foci and absent from BS cells. BLM encodes a DNA helicase, and proteins from
three missense alleles lack displacement activity. BLM transfected into BS cells reduces the
frequency of sister chromatid exchanges and restores BLM in the nucleus. Missense alleles …
Bloom syndrome (BS) is a rare autosomal recessive disorder characterized by growth deficiency, immunodeficiency, genomic instability, and the early development of cancers of many types. BLM, the protein encoded by BLM, the gene mutated in BS, is localized in nuclear foci and absent from BS cells. BLMencodes a DNA helicase, and proteins from three missense alleles lack displacement activity. BLM transfected into BS cells reduces the frequency of sister chromatid exchanges and restores BLM in the nucleus. Missense alleles fail to reduce the sister chromatid exchanges in transfected BS cells or restore the normal nuclear pattern. BLM complements a phenotype of aSaccharomyces cerevisiae sgs1 top3 strain, and the missense alleles do not. This work demonstrates the importance of the enzymatic activity of BLM for its function and nuclear localization pattern.
Am Soc Cell Biol