Background: Among the four RecQ homologues predicted from the Caenorhabditis elegans genomic DNA sequence, T04A11.6 is most similar to Bloom syndrome's protein in humans. To investigate a possible interaction of the protein with topoisomerase IIIalpha (TOP3alpha), as observed between TOP3 and RecQ homologues in yeast and human, the top3alpha gene expression was suppressed by RNA interference (RNAi) in the him-6(e1104) C. elegans strain which is mutated in T04A11.6 (F. Mueller & C. Wicky, personal communication).
Results: Germ cells in the gonads of the progeny him-6(e1104);top3alpha(RNAi) showed severe chromosomal abnormalities and were arrested during mitosis with a subsequent failure in meiotic entry. Most of the aberrant chromosomes were stained by the TUNEL assay but not by the SYTO12 dye, suggesting extensive DNA breaks not associated with apoptosis. The phenotypes in the germ cells of him-6(e1104);top3alpha(RNAi) were also observed in the progeny produced by double RNA interference of the top3alpha and him-6 gene expression, though at a reduced level. The over-expressed TOP3alpha and Him-6 proteins showed specific physical interaction in vitro, in agreement with the genetic interaction in C. elegans.
Conclusion: In C. elegans, TOP3alpha and the RecQ homologue (T04A11.6) contribute to genome stability during germ-line mitosis, probably by acting in a complex.
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http://dx.doi.org/10.1046/j.1356-9597.2001.00496.x | DOI Listing |
Adv Rheumatol
December 2024
Department of Immunology & Molecular Medicine, Sher-I-Kashmir Institute of Medical Sciences (SKIMS), Soura, Srinagar, Jammu and Kashmir, 190011, India.
Background: As a master immune system regulator, transforming growth factor β1 (TGF-β1) is closely linked to the complicated pathophysiology and development of systemic sclerosis (SSc), a multisystem fibrotic disease.
Objective: We aim to evaluate the transcriptional levels of TGF-β1 mRNA in PBMCs, assess the TGF-β1 serum levels of SSc patients, and compare them with those of healthy subjects.
Methods: PBMCs were isolated from whole blood of 50 SSc patients and in 30 healthy controls.
Cell Rep
December 2024
Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada; Biophysics Department, Faculty of Science, Cairo University, Giza 12613, Egypt. Electronic address:
Uncontrolled degradation and collapse of stalled replication forks (RFs) are primary sources of genomic instability, yet the molecular mechanisms for protecting forks from degradation/collapse remain to be fully elaborated. Here, we show that polynucleotide kinase-phosphatase (PNKP) localizes at stalled forks and protects stalled forks from excessive degradation. The loss of PNKP results in nucleolytic degradation of nascent DNA at stalled RFs.
View Article and Find Full Text PDFEur J Med Chem
February 2025
The First Affiliated Hospital, School of Pharmaceutical Science, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, China. Electronic address:
Evodiamine has been a promising lead structure with broad-spectrum antitumor activity. Druggability optimization is the most challenging part of evodiamine-based lead-to-candidate campaign. Amino acids as building blocks for conjugates are widely incorporated into approved drug and drug candidates, demonstrating highly attractive druggability.
View Article and Find Full Text PDFEur J Med Chem
February 2025
College of Pharmaceutical Sciences, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Zhejiang University of Technology, Hangzhou, 310014, China. Electronic address:
Addition of fluorine atoms into chemical compounds is a validated strategy to enhance their physical, chemical and biological properties. In this study, FL118, a novel camptothecin-related small molecule known for its unique mechanism of action and superior antitumor efficacy, was utilized as a foundational drug platform. By replacing the hydrogen atom at position 7 of FL118 with a fluoroaryl group, a diverse array of FL118 derivatives were synthesized.
View Article and Find Full Text PDFMolecules
November 2024
Medicinal Chemistry and Drug Discovery Research Centre, Swenam College, 210-6125 Sussex Avenue, Burnaby, BC V5H 4G1, Canada.
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