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Biology subjects

Basili, M.

Publications and source records attributed to Basili, M..

2 recordsLinked to original sources

Bacterioplankton Diversity and Distribution in Relation to Phytoplankton Community Structure in the Ross Sea surface waters

Primary productivity in the Ross Sea region is characterized by intense phytoplankton blooms whose temporal and spatial distribution are driven by changes in environmental conditions as well as interactions with the bacterioplankton community. Exchange of exudates, metabolism by-products and cofactors between the phytoplankton and the bacterioplankton communities drive a series of complex interactions affecting the micronutrient availability and co-limitation, as well as nutrient uptakes in Antarctic waters. Yet, the number of studies reporting the simultaneous diversity of the phytoplankton and bacterioplankton in Antarctic waters are limited. Here we report data on the bacterial diversity in relation to phytoplankton community in the surface waters of the Ross Sea during the austral summer 2017. Our results show partially overlapping bacterioplankton communities between the stations located in the Terra Nova Bay coastal waters and the Ross Sea open waters, suggesting that the two communities are subjected to different drivers. We show that the rate of diversity change between the two locations is influenced by both abiotic (salinity and the nitrogen to phosphorus ratio) and biotic (phytoplankton community structure) factors. Our data provides new insight into the coexistence of the bacterioplankton and phytoplankton in Antarctic waters.

microbiology↗

Ubiquitin-Specific-Processing Protease 47, A Novel 53BP1 regulator

53BP1 is a key DNA repair protein that regulates double strand break (DSB) repair pathway choice. It assembles a complex, whose loss reverses BRCA1 deficient cells sensitivity to PARP1 inhibitors potentially by antagonizing DSB end resection. 53BP1 is critical for immunoglobulin heavy chain class switch recombination (CSR), that is mediated by the generation and repair of DSBs. Here we identify a deubiquitylase, USP47, as a 53BP1 associated protein that regulates its function in these processes. USP47 loss results in 53BP1 protein instability in a proteasome dependent manner and in reduced 53BP1 ionizing radiation induced foci (IRIF). Like 53BP1, USP47 depletion results in enhanced homologous recombination repair, and defective immunoglobulin CSR. It is also required for resistance to DNA damaging agents. We identify a complex of 53BP1, USP47, Fen1, and Recql1 that regulates a microhomology mediated end joining (MMEJ), a repair pathway that is involved in CSR. Altogether, our findings implicate USP47 in DNA DSB repair at least through regulating a novel 53BP1 associated complex.

molecular biology↗