Ollye B. Conley, The Academy for Science and Foreign Language

The Alabama African American Historic Project has as its objective to research and document the history and culture of Huntsville, Alabama\u27s 19th Century African Americans. This project originated from a question asked by students during a field study to Huntsville\u27s historic Maple Hill Cemetery. While at the cemetery, students located graves of Civil War veterans and former governors of Alabama. Magnificent stories about their lives and outstanding contributions to the city were told. Where were the African Americans? was the question asked. This question evolved into Field Studies, Pictorial and Artifacts Exhibits, and Interdisciplinary Units

Construct validity of the Actiwatch-2 for assessing movement in people with profound intellectual and multiple disabilities

Background: Valid measures to assess either small or assisted performed movements of people with profound intellectual and multiple disabilities (PIMD) are required. We analysed the construct validity of the Actiwatch-2 to assess movement in people with PIMD. Method: Twenty-two persons with PIMD were video recorded while wearing an Actiwatch-2. We used 15s-partial-interval recording to record upper body movement, body position and activity situation. Multilevel analyses were used to evaluate if the Actiwatch-2, based on produced counts, could detect changes in these factors. Results: The presence versus absence of upper body movement and an activity situation in which participants were involved versus not involved resulted in significantly higher counts, with a large variety in predicted counts between participants. No relationship between body position and counts was found. Conclusions: The Actiwatch-2 seems able to assess obvious upper body movement in people with PIMD, and whether there is involvement in an activity situation

The ICC Compression Questionnaire: A Comprehensive Tool to Evaluate Compression Materials or Devices Applied in Subjects with Lymphedema or Chronic Venous Disease

Background: Compression therapy is an important part of the treatment of patients with lymphedema or chronic venous disease. However, there is no validated questionnaire evaluating the effect of compression and its acceptance by the patient. Therefore, the aims of this study were to construct a questionnaire evaluating the effect of compression and its acceptance by the patient, that is, the Dutch ICC Compression Questionnaire (ICC-CQ), to investigate its reliability and validity, and to translate it into English. Methods and Results: Eleven experts in applying compression and 51 Dutch patients with experience of using compression were involved in the construction process. One part of the ICC-CQ has to be completed by the patient and evaluates seven domains. The other part has to be completed by the health care provider and comprises three domains. Reliability and validity of the final version was investigated in a new group of 79 Dutch-speaking patients with lymphedema or chronic venous disease, wearing compression garments (N = 52) or bandages (N = 27). Except for one domain, the Intraclass Correlation Coefficients for test-rest/interrater reliability ranged from 0.55 to 0.93. Cronbach's alpha for internal consistency ranged from 0.71 to 0.97. Eighty-nine percent of the patients fully understood the questionnaire indicating good face validity, and 87% found it complete indicating good content validity. Construct validity was considered good since 10 out of 11 hypotheses were accepted. Conclusion: The ICC-CQ is the first reliable and valid questionnaire evaluating different kinds of compression and the experience by patients with lymphedema or chronic venous disease

PP1 and PP2A use opposite phospho-dependencies to control distinct processes at the kinetochore

PP1 and PP2A-B56 are major serine/threonine phosphatase families that achieve specificity by colocalizing with substrates. At the kinetochore, however, both phosphatases localize to an almost identical molecular space and yet they still manage to regulate unique pathways and processes. By switching or modulating the positions of PP1/PP2A-B56 at kinetochores, we show that their unique downstream effects are not due to either the identity of the phosphatase or its precise location. Instead, these phosphatases signal differently because their kinetochore recruitment can be either inhibited (PP1) or enhanced (PP2A) by phosphorylation inputs. Mathematical modeling explains how these inverse phospho-dependencies elicit unique forms of cross-regulation and feedback, which allows otherwise indistinguishable phosphatases to produce distinct network behaviors and control different mitotic processes. Furthermore, our genome-wide analysis suggests that these major phosphatase families may have evolved to respond to phosphorylation inputs in opposite ways because many other PP1 and PP2A-B56-binding motifs are also phospho-regulated

Protein Phosphatase-1α Interacts with and Dephosphorylates Polycystin-1

Polycystin signaling is likely to be regulated by phosphorylation. While a number of potential protein kinases and their target phosphorylation sites on polycystin-1 have been identified, the corresponding phosphatases have not been extensively studied. We have now determined that polycystin-1 is a regulatory subunit for protein phosphatase-1α (PP1α). Sequence analysis has revealed the presence of a highly conserved PP1-interaction motif in the cytosolic, C-terminal tail of polycystin-1; and we have shown that transfected PP1α specifically co-immunoprecipitates with a polycystin-1 C-tail construct. To determine whether PP1α dephosphorylates polycystin-1, a PKA-phosphorylated GST-polycystin-1 fusion protein was shown to be dephosphorylated by PP1α but not by PP2B (calcineurin). Mutations within the PP1-binding motif of polycystin-1, including an autosomal dominant polycystic kidney disease (ADPKD)-associated mutation, significantly reduced PP1α-mediated dephosphorylation of polycystin-1. The results suggest that polycystin-1 forms a holoenzyme complex with PP1α via a conserved PP1-binding motif within the polycystin-1 C-tail, and that PKA-phosphorylated polycystin-1 serves as a substrate for the holoenzyme

The protein phosphatase 1 regulator NIPP1 is essential for mammalian spermatogenesis

NIPP1 is one of the major nuclear interactors of protein phosphatase PP1. The deletion of NIPP1 in mice is early embryonic lethal, which has precluded functional studies in adult tissues. Hence, we have generated an inducible NIPP1 knockout model using a tamoxifen-inducible Cre recombinase transgene. The inactivation of the NIPP1 encoding alleles (Ppp1r8) in adult mice occurred very efficiently in testis and resulted in a gradual loss of germ cells, culminating in a Sertoli-cell only phenotype. Before the overt development of this phenotype Ppp1r8 -/- testis showed a decreased proliferation and survival capacity of cells of the spermatogenic lineage. A reduced proliferation was also detected after the tamoxifen-induced removal of NIPP1 from cultured testis slices and isolated germ cells enriched for undifferentiated spermatogonia, hinting at a testis-intrinsic defect. Consistent with the observed phenotype, RNA sequencing identified changes in the transcript levels of cell-cycle and apoptosis regulating genes in NIPP1-depleted testis. We conclude that NIPP1 is essential for mammalian spermatogenesis because it is indispensable for the proliferation and survival of progenitor germ cells, including (un)differentiated spermatogonia.publishe

Protein Phosphatase 1 inactivates Mps1 to ensure efficient Spindle Assembly Checkpoint silencing

Faithfull genome partitioning during cell division relies on the Spindle Assembly Checkpoint (SAC), a conserved signaling pathway that delays anaphase onset until all chromosomes are attached to spindle microtubules. Mps1 kinase is an upstream SAC regulator that promotes the assembly of an anaphase inhibitor through a sequential multi-target phosphorylation cascade. Thus, the SAC is highly responsive to Mps1, whose activity peaks in early mitosis as a result of its T-loop autophosphorylation. However, the mechanism controlling Mps1 inactivation once kinetochores attach to microtubules and the SAC is satisfied remains unknown. Here we show in vitro and in Drosophila that Protein Phosphatase 1 (PP1) inactivates Mps1 by dephosphorylating its T-loop. PP1-mediated dephosphorylation of Mps1 occurs at kinetochores and in the cytosol, and inactivation of both pools of Mps1 during metaphase is essential to ensure prompt and efficient SAC silencing. Overall, our findings uncover a mechanism of SAC inactivation required for timely mitotic exit.We thank Geert Kops (UMC, Utrecht, The Netherlands), Thomas Maresca (University of Massachu-setts Amherst, USA) and Christian Lehner (University of Zurich, Switzerland) for antibodies, con-structs and fly stocks. We thank Carla Sofia Lopes (i3S, IBMC, University of Porto) and all the members of the Sunkel laboratory for critical and helpful discussions. This article is a result of the project Norte-01-0145-FEDER-000029 - Advancing Cancer Research: From basic knowledge to application, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). MO is supported by a fellowship from the GABBA PhD program from the University of Porto, PD/BD/105746/2014. JB is supported by an FCT PhD grant SFRH/BD/87871/2012. CC is sup-ported by an FCT investigator position and funding (IF/01755/2014). HM is funded by PRECISE and CODECHECK grants from the European Research Council, FLAD Life Science 2020, and the Louis-Jeantet Young Investigator Career Award

Mouse Rif1 is a regulatory subunit of protein phosphatase 1 (PP1)

International audienceRif1 is a conserved protein that plays essential roles in orchestrating DNA replication timing, controlling nuclear architecture, telomere length and DNA repair. However, the relationship between these different roles, as well as the molecular basis of Rif1 function is still unclear. The association of Rif1 with insoluble nuclear lamina has thus far hampered exhaustive characterization of the associated protein complexes. We devised a protocol that overcomes this problem, and were thus able to discover a number of novel Rif1 interactors, involved in chromatin metabolism and phosphorylation. Among them, we focus here on PP1. Data from different systems have suggested that Rif1-PP1 interaction is conserved and has important biological roles. Using mutagenesis, NMR, isothermal calorimetry and surface plasmon resonance we demonstrate that Rif1 is a high-affinity PP1 adaptor, able to out-compete the well-established PP1-inhibitor I2 in vitro. Our conclusions have important implications for understanding Rif1 diverse roles and the relationship between the biological processes controlled by Rif1