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Centrosomal protein of 192 kDa (CEP192) is a scaffolding protein that recruits the mitotic protein kinases Aurora A and PLK1 to the centrosome. Here we demonstrate that CEP192 also recruits the type one protein phosphatase (PP1) via a highly conserved KHVTF docking motif. The threonine of the KHVTF motif is phosphorylated during mitosis and protein kinase inhibition studies suggest this to be a PLK1-dependent process.

Background The NNEdPro Core Team, Bhavishya Shakti Researchers and Inner Wheel Club of Greater Calcutta launched Mobile Teaching Kitchens as a nutritional education tool in two Indian slums in February 2018 to improve awareness of diet diversity and disease prevention by using locally sourced foods and cooking skills. Local volunteers, trained in healthy cooking, transferred core nutritional principals by cooking sustainable, nutritional and affordable meals. They followed a “See one, Do one and Teach one” model to transfer knowledge to their peers where markers of malnutrition were assessed before and after this programme. Objective To evaluate the efficacy of using mobile teaching kitchens to provide nutrition education through cooking, teaching healthy eating to a disadvantaged community in the urban slums of India. Study Design, Settings, Participants Longitudinal evaluation of mothers and children in RG Kar Canal Slum and Chetla Slum in Kolkata, India from 2018 to 2019. Measurable Outcome/Analysis Anthropometric and clinical signs of the children were assessed in person, alongside assessment of knowledge, attitudes and practice of the mothers through questionnaires. Results Preliminary measurements post-analysis from both slums (n = 14) showed that overall anthropometric measures of health in the mothers remained static. There was a mean change of 2.75cm growth in height in children. Other markers of nutritional status such as weight and mid-upper arm circumference did not significantly change. Statistically significant changes were seen in self-perceived nutritional knowledge about dietary protein sources, where the median response increased from 2 to 3 out of 5 (5 indicating excellent understanding) (P Conclusion Overall improvement in clinical status and nutritional knowledge was seen using Mobile Teaching Kitchens as an educational tool. Further evaluation of this particular teaching method is warranted due to the small sample size and heterogeneous results. Funding British Medical Association (BMA), Economic and Social Research Council (ESRC), Global Open Data for Agriculture and Nutrition (GODAN), The British Dietetics Association (BDA), University of Cambridge.

The requirement for the serine/threonine protein kinase ATM in coordinating the cellular response to DNA damage induced by ionizing radiation has been studied extensively. Many of the anti-tumor chemotherapeutics in clinical use today cause DNA double strand breaks; however, few have been evaluated for their ability to modulate ATM-mediated pathways. We have investigated the requirement for ATM in the cellular response to doxorubicin, a topoisomerase II-stabilizing drug. Using several ATM-proficient and ATM-deficient cell lines, we have observed ATM-dependent nuclear accumulation of p53 and ATM-dependent phosphorylation of p53 on seven serine residues. This was accompanied by an increased binding of p53 to its cognate binding site, suggesting transcriptional competency of p53 to activate its downstream effectors. Treatment of cells with doxorubicin led to the phosphorylation of histone H2AX on serine 139 with dependence on ATM for the initial response. Doxorubicin treatment also stimulated ATM autophosphorylation on serine 1981 and the ATM-dependent phosphorylation of numerous effectors in the ATM-signaling pathway, including Nbs1 (Ser(343)), SMC1 (Ser(957)), Chk1 (Ser(317) and Ser(345)), and Chk2 (Ser(33/35) and Thr(68)). Although generally classified as a topoisomerase II-stabilizing drug that induces DNA double strand breaks, doxorubicin can intercalate DNA and generate reactive oxygen species. Pretreatment of cells with the superoxide scavenger ascorbic acid had no effect on the doxorubicin-induced phosphorylation and accumulation of p53. In contrast, preincubation of cells with the hydroxyl radical scavenger, N-acetylcysteine, significantly attenuated the doxorubicin-mediated phosphorylation and accumulation of p53, p53-DNA binding, and the phosphorylation of H2AX, Nbs1, SMC1, Chk1, and Chk2, suggesting that hydroxyl radicals contribute to the doxorubicin-induced activation of ATM-dependent pathways.

ATM is mutated in the human genetic disorder ataxia telangiectasia, which is characterized by ataxia, immune defects, and cancer predisposition. Cells that lack ATM exhibit delayed up-regulation of p53 in response to ionizing radiation. Serine 15 of p53 is phosphorylated in vivo in response to ionizing radiation, and antibodies to ATM immunoprecipitate a protein kinase activity that, in the presence of manganese, phosphorylates p53 at serine 15. Immunoprecipitates of ATM also phosphorylate PHAS-I in a manganese-dependent manner. Here we have purified ATM from human cells using nine chromatographic steps. Highly purified ATM phosphorylated PHAS-I, the 32-kDa subunit of RPA, serine 15 of p53, and Chk2 in vitro. The majority of the ATM phosphorylation sites in Chk2 were located in the amino-terminal 57 amino acids. In each case, phosphorylation was strictly dependent on manganese. ATM protein kinase activity was inhibited by wortmannin with an IC(50) of approximately 100 nM. Phosphorylation of RPA, but not p53, Chk2, or PHAS-I, was stimulated by DNA. The related protein, DNA-dependent protein kinase catalytic subunit, also phosphorylated PHAS-I, RPA, and Chk2 in the presence of manganese, suggesting that the requirement for manganese is a characteristic of this class of enzyme.