TOP

Research Article

Split Viewer

Mol. Cells 2005; 20(2): 228-234

Published online January 1, 1970

© The Korean Society for Molecular and Cellular Biology

Deficiency of Bloom’s Syndrome Protein Causes Hypersensitivity of C. elegans to Ionizing Radiation but Not to UV Radiation, and Induces p53-dependent Physiological Apoptosis

Yun Mi Kim, Insil Yang, Jiyeung Lee, Hyeon-Sook Koo

Abstract

Caenorhabditis elegans him-6 mutants, which show a high incidence of males and partial embryonic lethality, are defective in the orthologue of human Bloom’s syndrome protein (BLM). When strain him-6(e1104) containing a missense him-6 mutation was irradiated with g-rays during germ cell development or embryogenesis, embryonic lethality was higher than in the wild type, suggesting a critical function of the wild type gene in mitotic and pachytene stage germ cells as well as in early embryos. Even in the absence of g-irradiation, apoptosis was elevated in the germ cells of the him-6 strain and this increase was dependent on a functional p53 homologue (CEP-1), suggesting that spontaneous DNA damage accumulates due to him-6 deficiency. However, induction of germline apoptosis by ionizing radiation was not significantly affected by the deficiency, indicating that HIM-6 has no role in the induction of apoptosis by exogenous DNA damage. We conclude that the C. elegans BLM orthologue is involved in DNA repair in promeiotic cells undergoing homologous recombination, as well as in actively dividing germline and somatic cells.

Keywords Apoptosis; DNA Damage; him-6; RecQ

Article

Research Article

Mol. Cells 2005; 20(2): 228-234

Published online October 31, 2005

Copyright © The Korean Society for Molecular and Cellular Biology.

Deficiency of Bloom’s Syndrome Protein Causes Hypersensitivity of C. elegans to Ionizing Radiation but Not to UV Radiation, and Induces p53-dependent Physiological Apoptosis

Yun Mi Kim, Insil Yang, Jiyeung Lee, Hyeon-Sook Koo

Abstract

Caenorhabditis elegans him-6 mutants, which show a high incidence of males and partial embryonic lethality, are defective in the orthologue of human Bloom’s syndrome protein (BLM). When strain him-6(e1104) containing a missense him-6 mutation was irradiated with g-rays during germ cell development or embryogenesis, embryonic lethality was higher than in the wild type, suggesting a critical function of the wild type gene in mitotic and pachytene stage germ cells as well as in early embryos. Even in the absence of g-irradiation, apoptosis was elevated in the germ cells of the him-6 strain and this increase was dependent on a functional p53 homologue (CEP-1), suggesting that spontaneous DNA damage accumulates due to him-6 deficiency. However, induction of germline apoptosis by ionizing radiation was not significantly affected by the deficiency, indicating that HIM-6 has no role in the induction of apoptosis by exogenous DNA damage. We conclude that the C. elegans BLM orthologue is involved in DNA repair in promeiotic cells undergoing homologous recombination, as well as in actively dividing germline and somatic cells.

Keywords: Apoptosis, DNA Damage, him-6, RecQ

Mol. Cells
Sep 30, 2023 Vol.46 No.9, pp. 527~572
COVER PICTURE
Chronic obstructive pulmonary disease (COPD) is marked by airspace enlargement (emphysema) and small airway fibrosis, leading to airflow obstruction and eventual respiratory failure. Shown is a microphotograph of hematoxylin and eosin (H&E)-stained histological sections of the enlarged alveoli as an indicator of emphysema. Piao et al. (pp. 558-572) demonstrate that recombinant human hyaluronan and proteoglycan link protein 1 (rhHAPLN1) significantly reduces the extended airspaces of the emphysematous alveoli by increasing the levels of TGF-β receptor I and SIRT1/6, as a previously unrecognized mechanism in human alveolar epithelial cells, and consequently mitigates COPD.

Share this article on

  • line

Molecules and Cells

eISSN 0219-1032
qr-code Download