New 3-D model of a DNA-regulating complex in human cells provides cancer clues — ScienceDaily

Scientists have created an unprecedented 3-dimensional structural model of a key molecular “machine” known as the BAF complex, which modifies DNA architecture and is frequently mutated in cancer and some other diseases. The researchers, led by Cigall Kadoch, PhD, of Dana-Farber Cancer Institute, have reported the first 3-D structural “picture” of BAF complexes purified directly from human cells in their native states — rather than artificially synthesized in the laboratory -providing an opportunity to spatially map thousands of cancer-associated mutations to specific locations within the complex.

“A 3-D structural model, or ‘picture,’ of how this complex actually looks inside the nucleus of our cells has remained elusive — until now,” says Kadoch. The newly obtained model represents “the most complete picture of the human BAF complex achieved to date,” said the investigators, reporting in the journal Cell.

These new findings “provide a critical foundation for understanding human disease-associated mutations

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Researchers create p16-Cre ERT2 -tdTomato mouse model to characterize in vivo senescent cells

Cell senescence is a state of permanent cell cycle arrest that was initially defined for cells grown in cell culture. It plays a key role in age-associated organ dysfunction and age-related diseases such as cancer, but the in vivo pathogenesis is largely unclear.

A research team led by Professor Makoto Nakanishi of the Institute of Medical Science, the University of Tokyo, generated a p16-Cre ERT2 -tdTomato mouse model to characterize in vivo p16 high cells at the single-cell level.

They found tdTomato-positive p16 high cells detectable in all organs, which were enriched with age. They also found that these cells failed to proliferate and had half-lives ranging from 2.6 to 4.2 months, depending on the tissue examined.

Single-cell transcriptomics in the liver and kidneys revealed that p16 high cells were present in various cell types, though most dominant in hepatic endothelium and

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