4433-40-3Relevant articles and documents
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Johnson,Litzinger
, p. 1940 (1936)
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Bioorthogonal Chemical Signature Enabling Amplified Visualization of Cellular Oxidative Thymines
Bai, Min,Cao, Xiaowen,Chen, Feng,Xue, Jing,Zhao, Yue,Zhao, Yongxi
, p. 10495 - 10501 (2021)
Cellular oxidative thymines, 5-hydroxymethyluracil (5hmU) and 5-formyluracil (5fU), are found in the genomes of a diverse range of organisms, the distribution of which profoundly influence biological processes and living systems. However, the distribution of cellular oxidative thymines has not been explored because of lacking both specific bioorthogonal labeling and sensitivity methods for single-cell analysis. Herein, we report a bioorthogonal chemical signature enabling amplified visualization of cellular oxidative thymines in single cells. The synthesized ATP-γ-alkyne, an ATP analogue with bioorthogonal tag modified on γ-phosphate can be specifically linked to cellular 5hmU by chemoenzymatic labeling. DNA with 5-alkynephosphomethyluracil were then clicked with azide (N3)-modified 5hmU-primer. Identification of 5fU is based on selective reduction from 5fU to 5hmU, subsequent chemoenzymatic labeling of the newly generated 5hmU, and cross-linking with N3-modified 5fU-primer via click chemistry. Then, all of the 5hmU and 5fU sites are encoded with respective circularized barcodes. These barcodes are simultaneously amplified for multiplexed single-molecule imaging. The above two kinds of barcodes can be simultaneously amplified for differentiated visualization of 5hmU and 5fU in single cells. We find these two kinds of cellular oxidative thymines are spatially organized in a cell-type-dependent style with cell-to-cell heterogeneity. We also investigate their multilevel subcellular information and explore their dynamic changes during cell cycles. Further, using DNA sequencing instead of fluorescence imaging, our proposed bioorthogonal chemical signature holds great potential to offer the sequence information of these oxidative thymines in cells and may provide a reliable chemical biology approach for studying the whole-genome oxidative thymines profiles and insights into their functional role and dynamics in biology.
FUSED PYRIMIDINE COMPOUNDS, COMPOSITIONS AND MEDICINAL APPLICATIONS THEREOF
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Paragraph 0308, (2021/04/02)
The present disclosure relates to a class of fused pyrimidine compounds of Formula I, their stereoisomers, tautomers, pharmaceutically acceptable salts, polymorphs, solvates, and hydrates thereof. The present disclosure also relates to a process of preparation of these fused pyrimidine compounds, and to pharmaceutical compositions containing them.
Targeting the nucleotide salvage factor DNPH1 sensitizes BRCA-deficient cells to PARP inhibitors
Fugger, Kasper,Bajrami, Ilirjana,Dos Santos, Mariana Silva,Young, Sarah Jane,Kunzelmann, Simone,Kelly, Geoff,Hewitt, Graeme,Patel, Harshil,Goldstone, Robert,Carell, Thomas,Boulton, Simon J.,MacRae, James,Taylor, Ian A.,West, Stephen C.
, p. 156 - 165 (2021/05/03)
Mutations in the BRCA1 or BRCA2 tumor suppressor genes predispose individuals to breast and ovarian cancer. In the clinic, these cancers are treated with inhibitors that target poly(ADP-ribose) polymerase (PARP). We show that inhibition of DNPH1, a protein that eliminates cytotoxic nucleotide 5-hydroxymethyl-deoxyuridine (hmdU) monophosphate, potentiates the sensitivity of BRCA-deficient cells to PARP inhibitors (PARPi). Synthetic lethality was mediated by the action of SMUG1 glycosylase on genomic hmdU, leading to PARP trapping, replication fork collapse, DNA break formation, and apoptosis. BRCA1-deficient cells that acquired resistance to PARPi were resensitized by treatment with hmdU and DNPH1 inhibition. Because genomic hmdU is a key determinant of PARPi sensitivity, targeting DNPH1 provides a promising strategy for the hypersensitization of BRCA-deficient cancers to PARPi therapy.
