Journal Of Biological Chemistry Research Articles

Abstract 204: Disruption of the RACK1/PP2A complex results in a decrease in the adhesion, proliferation, migration and invasion capabilities of breast cancer cells

Abstract Conflicting reports implicate the scaffolding protein RACK1 in the progression of breast cancer. PP2A has a well-established role as a tumour suppressor within signalling pathways but is also known to play a pro-carcinogenic role in certain circumstances [1]. RACK1 has been identified as a direct binding partner of PP2A to regulate cell migration and stabilize PP2A activity [2]. Our objective was to further characterise the interaction between PP2A and RACK1 in breast cancer cells. The PP2A holoenzyme is assembled in MCF-7 cells and we found that both the C subunit and A subunit of PP2A are assembled on the RACK1 scaffold. We used immobilized peptide arrays representing the entire PP2A-Catalytic protein to identify amino acids on the C subunit of PP2A that are required for the binding of RACK1. Once identified, these sites were mutated and expressed in the context of the full length PP2A C subunit protein and stable cell lines were generated. When the RACK1/PP2A interaction was disrupted, cells exhibited reduced PP2A phosphatase activity, confirming the role for RACK1 in stabilizing PP2A activity. We used the stable cell lines to determine that disruption of the RACK1/PP2A complex also reduces the adhesion, proliferation, migration and invasion of this breast cancer cell model. The work has significantly advanced our understanding of the RACK1/PP2A complex and indicates a pro-carcinogenic role for the RACK1/PP2A complex. This work has highlighted a novel mechanism to target PP2A activity and may provide a potential therapeutic target in the treatment of breast cancer. 1. Kiely, M. and P.A. Kiely, PP2A: The Wolf in Sheep's Clothing? Cancers, 2015. 7(2): p. 648-669. 2. Kiely, P.A., et al., Tyrosine 302 in RACK1 is essential for insulin-like growth factor-I-mediated competitive binding of PP2A and β1 integrin and for tumor cell proliferation and migration. Journal of Biological Chemistry, 2008. 283(34): p. 22952-22961. Citation Format: Maeve Kiely, Rosemary O’Connor, David Adams, George S. Baillie, Patrick A. Kiely. Disruption of the RACK1/PP2A complex results in a decrease in the adhesion, proliferation, migration and invasion capabilities of breast cancer cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 204.

DEFICIENCY OF NEURONAL P38A-MAPK ATTENUATES AMYLOID PATHOLOGY AND COGNITIVE DEFICITS IN ALZHEIMER’S MOUSE MODEL

Amyloid β (Aβ) damages neurons and triggers microglial inflammatory activation in the Alzheimer’s disease (AD) brain. Neuroinflammation potentially up-regulates BACE1 expression and increases Aβ production. Recently, we have observed that deletion of p38α-MAPK, a inflammation-responding kinase, in neurons increases the lysosomal degradation of BACE1 protein, thereby reducing in Aβ generation in neuronal cells (Schnöder et al., Journal of Biological Chemistry, Vol. 291, No. 5, pp. 2067–2079, January 29, 2016). We follow this study and delete p38α-MAPK specifically in neurons of Aβ-precursor protein (APP)-transgenic mice with Cre-Lox technique. By using immunohistochemical and biochemical methods, as well as behavior tests, we determined the role of neuronal deletion of p38α-MAPK on Aβ pathology. We can clearly demonstrate that neuronal deficiency of p38α-MAPK significantly decreases cerebral Aβ level, and improves cognitive function in 9-month-old APP-transgenic mice. Thus, our study demonstrates that p38α-MAPK plays a critical role in the regulation of Aβ generation and AD pathogenesis, and suggests that p38α-MAPK might be a novel molecular target for AD therapy.

High-Throughput, High-Resolution Peptide Maps

Genetic Engineering & Biotechnology NewsVol. 36, No. 12 Bioprocessing Tech NoteHigh-Throughput, High-Resolution Peptide MapsRowan Moore and Martin SamonigRowan MooreRowan Moore (E-mail Address: rowan.moore@thermofisher.com) is vertical marketing manager for pharmaceutical and biopharmaceutical HPLC and IC and Martin Samonig is a biopharmaceutical HPLC and MS applications scientist at Thermo Fisher Scientific. Website: www.thermofisher.com/builtforbiopharma.Search for more papers by this author and Martin SamonigSearch for more papers by this authorPublished Online:8 Jun 2016https://doi.org/10.1089/gen.36.12.11AboutSectionsView articleView Full TextPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View articleFiguresReferencesRelatedDetailsCited byStructural and compositional diversity of fibrillin microfibrils in human tissues16 February 2018 | Journal of Biological Chemistry, Vol. 293, No. 14 Volume 36Issue 12Jun 2016 InformationCopyright © GEN PublishingTo cite this article:Rowan Moore and Martin Samonig.High-Throughput, High-Resolution Peptide Maps.Genetic Engineering & Biotechnology News.Jun 2016.20-21.http://doi.org/10.1089/gen.36.12.11Published in Volume: 36 Issue 12: June 8, 2016PDF download

Introduction to Biofilms Thematic Minireview Series

The biofilms that many bacteria and fungi produce enable them to form communities, adhere tightly to surfaces, evade host immunity, and resist antibiotics. Pathogenic microorganisms that form biofilms are very difficult to eradicate and thus are a frequent source of life-threatening, hospital-acquired infections. This series of five minireviews from the Journal of Biological Chemistry provides a broad overview of our current understanding of biofilms and the challenges that remain. The structure, biosynthesis, and biological function of the biofilms produced by pathogenic fungi are the subject of the first article, by Sheppard and Howell. Gunn, Bakaletz, and Wozniak focus on the biochemistry and structure of bacterial biofilms, how these structures enable bacteria to evade host immunity, and current and developing strategies for overcoming this resistance. The third and fourth articles present two of the best understood cell signaling pathways involved in biofilm formation. Valentini and Filloux focus on cyclic di-GMP, while Kavanaugh and Horswill discuss the quorum-sensing (agr) system and the relationship between quorum sensing and biofilm formation. Mechanisms of antibiotic resistance, particularly the role of efflux pumps and the development of persister cells, are the topics of the final article by Van Acker and Coenye. The advances described in this series guarantee that ongoing interdisciplinary and international efforts will lead to new insights into the basic biology of biofilm formation, as well as new strategies for therapeutic interventions.

590 UVB generates microvesicle particles via Platelet-activating Factor-receptor signaling: a novel pathway by which a skin-specific stimulus exerts systemic effects

590 UVB generates microvesicle particles via Platelet-activating Factor-receptor signaling: a novel pathway by which a skin-specific stimulus exerts systemic effects

A Quarter Century of Glycobiology.

As was pointed out in the editorial in the very first issue ofGlycobiology (Hart 1990), the study of the biology of carbohydrates and glycoconjugates dates back to the earliest foundations of biochemistry. What is now the Society for Glycobiology dates back to small meetings organized by the founding fathers of our field, which took place in the early 1960s (for a historical review, see Silbert at http://www. glycobiology.org/files/sfg_history.pdf ). The Society for Complex Carbohydrates was formalized in 1972, and it was agreed to have a Society meeting every year in the fall. In these early days, much of the work in the field was focused on the chemical and structural analyses of glycoconjugates, while the biological functions of glycans remained largely enigmatic. Given the limited technology of the period, the accomplishments of these early glycoscientists are remarkable! By the late 1980s, it was evident that glycoconjugates play key roles in nearly every aspect of biology, including major diseases that affect mankind. Indeed, a number of “glyco-focused” biotech companies were created leading to renewed interest in our rapidly growing field. In addition, technological advances allowed for meaningful research into the structure/functions of complex glycans in complex biological systems. The realization that glycans are critically important to nearly all aspects of biology led to coining of the term “glycobiology” (Rademacher et al. 1988). During this era, papers on glycoconjugates were published in a wide array of different types of journals, ranging from those focused on mostly chemistry to others focused mainly on biology. Thus, it was realized that glycobiology papers were either buried within thick issues of general biochemistry journals or diluted among papers in highly specialized journals focused mostly on immunology, neurobiology, virology, developmental biology and many other disciplines. In 1989, after discussions with Oxford University Press, plans to create the journal Glycobiology were finalized. An editorial board of leaders in all areas of our field was selected. It was planned that each issue of Glycobiology would contain invited mini-reviews, which would convey exciting breakthroughs in an easily readable format accessible to the general bioscience communities. Each issue would also have a “Glyco-Forum” section to highlight news, meeting announcements, and to provide a vehicle for sharing ideas not appropriate for formal research publications. An original aim of the Journal was to not only publish the best science in glycobiology, but also to keep publication times as rapid as possible. The first issue of Glycobiology was published in September of 1990 with Gerald W. Hart as Editor-in-Chief, and Anne Dell, Akira Kobata and DirkH. van den Eijnden serving as Executive Editors. Both the Editors and Board members were selected from all over the world, reflecting the international focus of the new journal. The first cover of the journal showed a Haworth Projection of a hexose enclosing an electron micrograph of the Golgi (Figure 1, reproduced on the cover of this issue), reflecting the importance of this organelle in the biosynthesis of complex glycans. In the early 1990s, it became apparent to the Board of Directors of the Society for Complex Carbohydrates that the Society’s name did not adequately reflect the new directions of the field into myriad diverse areas of biology. At the 22nd Annual Meeting (1993) in Puerto Rico, the membership nearly unanimously voted to both change the name of the Society to “Society for Glycobiology” and also to make Glycobiology the Society’s official journal (Hart 1994). By 1996, it was very clear that Glycobiology was not only the leading specialty journal in our field, but also thatGlycobiology ranked highly in terms of its relative impact among all biochemical journals, only just behind Journal of Biological Chemistry and Journal of Molecular Biology but ahead of Proteins, Biochemistry, Biochemical Journal and European Journal of Biochemistry (Hart 1996). Figure 1: Cover of inaugural issue. Glycobiology, 2015, vol. 25, no. 12, 1321–1322 doi: 10.1093/glycob/cwv090 Glyco-Forum

Memorial: Tatsushi Muta, 1963-2013.

Dr. Tatsushi Muta was a biochemist who died September 11, 2013, at the age of 50 at Tohoku University Hospital, Miyagi, Japan. Tatsu and I were in the process of preparing a draft of a manuscript, which is published in this edition of the Journal of Leukocyte Biology [1]. During his long career, Tatsu spearheaded research that led to the discovery and functional analysis of IκB-ζ, which has been instrumental in our understanding of the biologic homeostatic mechanisms of IκB-ζ. Unfortunately, despite overcoming challenges related to the East Japan great earthquake disaster on March 11, 2011, which damaged his laboratory at Tohoku University, this work became his last work. Tatsu was born on July 24, 1963, and grew up in Nagasaki, Japan. He attended Nagasaki-Kita High School, where he played baseball, and he dreamed of playing at Koshien, where the Japan National High School Baseball Tournament is held. He also had a passion for life sciences studies, guiding his decision to attend Kyusyu University in 1982. During graduate school, Tatsu worked in the laboratory of Dr. Sadaaki Iwanaga, who discovered the gram-negative bacterial endotoxin LPS. Tatsu was a very productive student and went on to receive a Master’s degree and Ph.D. while conducting research in Dr. Iwanaga’s laboratory. During these studies, Tatsu and his colleagues cloned proclotting enzyme and factor C, which play an important role in the coagulation cascade in the horseshoe crab. Tatsu also published 3 first-author papers, including 1 manuscript in the Journal of Biological Chemistry, Advances in Experimental Medicine and Biology, and Journal of Biochemistry [2–4]. He then became an assistant professor in Dr. Iwanaga’s laboratory and contributed to the identification of factors B and G, which are also involved in the coagulation cascade in the horseshoe crab.

Memórias and the Journal Citation Reports

We, as many other journal editors, have been looking at the recent release of the 2014 Journal Citation Reports by Thompson-Reuters. The results for the Memorias do Instituto Oswaldo Cruz have again been gratifying; our two-year impact factor has increased to 1.592 while the Memorias is one of the few Latin American journals with a five-year impact factor above 2.0. The other indices released by Thomson-Reuters have provided even more impressive news for the Memorias. The journal continues not only to be the most highly cited scientific periodical (with 5,899 citations in 2014), but also has the highest Eigenfactor score (0.086) of any Latin American journal. The Eigenfactor is like the impact factor, but gives more weight to citations from highly cited journals and less weight to citations from less cited journals, and self-citations are also omitted from the calculation. However when we compare the Memorias to international journals worldwide the results are not so impressive. Here we have the same struggle as many other journals published in developing countries. That is, how can we attract the best manuscripts from our region, which tend to be sent by their authors to highly cited international journals? Even so the Memorias, in the tropical medicine category is classified within the top ten journals, using ranking by any of the indices mentioned above, while among parasitology journals the Memorias is ranked in the third quartile by impact factor. Tropical medicine and parasitology are the only two categories were Thomson-Reuters classifies the Memorias. Other data from the Journal Citation Reports show the changes in journal publishing. One is the growth of megajournals. There are now over 100 journals that publish 1,000 articles per year. PLoS One, that published more than 30,000 articles last year, heads the list. While many are traditional journals, such as Proceedings of the National Academy of Sciences and the Journal of Biological Chemistry, there are several newer open access (OA) journals as for instance the Scientific Reports from the Nature Publishing Group, which published nearly 4,000 articles with an impact factor of over 5.0. Another trend has been the rise of OA journals. In several categories, such as public health, tropical medicine and parasitology, the ranking of journals by impact factor is headed by OA journals. New OA journals such as eLife, which is sponsored by major research funders, have received their first impact factors (an impressive score of nearly 10) and flagship journals published by the major OA publishers have seen increases in their impact. Brazil is fortunate to have most of its scientific journals published as OA. This is principally due to the SciELO project, which provides an OA platform for selected Brazilian journals, including the Memorias. Many of the Brazilian journals, including the Memorias, are published under a special model of OA where no fees are charged to authors and readers sometimes referred to as Platinum Open Acess. These journals are funded by a variety of public resources (including institutional and research agency funding). This together with the pro bonowork of their editors and reviewers allows for a form of open public access: authors can contribute to the scientific literature and any member of the public can access this literature without any financial barriers. The scientific publication process is thus funded by the Brazilian taxpayers as a logical complement to their investment in scientific research. With this distinctive form of OA together with improvements in the quality of its contents and better dissemination of the journal we hope that the Memorias will continue to increase its impact in the coming years.

Abstract 35: Diacylglycerol kinase zeta-mediated regulation of mTOR and SREBP-1 offers new opportunities for cancer management

Abstract Diacylglycerol (DAG) and phosphatidic acid (PA) are two lipids that lie at the core of several metabolic and signaling pathways, which allows integrated control of cell growth and nutrient sensing with cell metabolism. Diacylglycerol kinases (DGK) are a family of enzymes that balance the levels of both lipids. Some DGK isoforms, mainly DGKα, have been recently suggested as potential targets for cancer treatment (Dominguez et al, 2013; Torres-Ayuso et al, 2014). Previous observations from us indicate that the DGKζ isoform contributes the most to DGK activity in cancer cells, and DGKζ-derived PA is required for mTOR activation, a master regulator of cell growth and metabolism (Avila-Flores et al, 2005). To address the potential of DGKζ as new therapeutic target for cancer treatment, we used several breast and colon cancer cell lines, and analyzed the effect of its pharmacological inhibition or siRNA-mediated knock down in the proliferation, survival and metabolism of these cells. We found that DGKζ protein levels where higher in malignant cells compared to their non-transformed counterparts, and its depletion abrogated cancer cell growth in colony assays. DGKζ was prominent over other PA sources to activate mTOR, and its activity was induced by rapamycin. We also investigated whether DGKζ-derived PA functions were coordinated with DAG metabolism and signaling. We observed that DGKζ-dependent DAG consumption was crucial for cell homeostasis via control of the SREBP-1 transcription factor, which was negatively regulated by DAG. Our data provide new evidence of the crosstalk between mTOR and lipid metabolism, and suggest that DGKζ represents an effective target for cancer control. References Avila-Flores A, Santos T, Rincon E, Merida I (2005) Modulation of the mammalian target of rapamycin pathway by diacylglycerol kinase-produced phosphatidic acid. The Journal of biological chemistry 280: 10091-10099 Dominguez CL, Floyd DH, Xiao A, Mullins GR, Kefas BA, Xin W, Yacur MN, Abounader R, Lee JK, Wilson GM, Harris TE, Purow BW (2013) Diacylglycerol kinase alpha is a critical signaling node and novel therapeutic target in glioblastoma and other cancers. Cancer discovery 3: 782-797 Torres-Ayuso P, Daza-Martin M, Martin-Perez J, Avila-Flores A, Merida I (2014) Diacylglycerol kinase alpha promotes 3D cancer cell growth and limits drug sensitivity through functional interaction with Src. Oncotarget 5: 9710-9726 Citation Format: PEDRO Torres-Ayuso, David Jones, Maria Tello-Lafoz, Antonia Avila-Flores, Isabel Merida. Diacylglycerol kinase zeta-mediated regulation of mTOR and SREBP-1 offers new opportunities for cancer management. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 35. doi:10.1158/1538-7445.AM2015-35

Using distant supervised learning to identify protein subcellular localizations from full-text scientific articles

Databases of curated biomedical knowledge, such as the protein–locations reflected in the UniProtKB database, provide an accurate and useful resource to researchers and decision makers. Our goal is to augment the manual efforts currently used to curate knowledge bases with automated approaches that leverage the increased availability of full-text scientific articles. This paper describes experiments that use distant supervised learning to identify protein subcellular localizations, which are important to understand protein function and to identify candidate drug targets. Experiments consider Swiss-Prot, the manually annotated subset of the UniProtKB protein knowledge base, and 43,000 full-text articles from the Journal of Biological Chemistry that contain just under 11.5 million sentences. The system achieves 0.81 precision and 0.49 recall at sentence level and an accuracy of 57% on held-out instances in a test set. Moreover, the approach identifies 8210 instances that are not in the UniProtKB knowledge base. Manual inspection of the 50 most likely relations showed that 41 (82%) were valid. These results have immediate benefit to researchers interested in protein function, and suggest that distant supervision should be explored to complement other manual data curation efforts.

Electrochemical Biosensor for Faster Diagnosis of Alpha-1-Antitrypsin Deficiency

In the medical field, new and quicker methods for the diagnosis of diseases are sought. Being able to diagnose the disease earlier and easier typically increases the life expectancy of a patient. As such, electrochemical biosensors provide a potentially quicker method to diagnose certain diseases. A biosensor is a device that can directly convert biological activity into an electronic signal, which is done at the nanoscale.[1] For a specific case, Alpha-1-antitrypsin (A1AT) Deficiency (A1AD) is an underdiagnosed disease that is caused by subtle changes in the protein composition that could possibly be detected through the use of an electrochemical biosensor. A1AD is a potentially debilitating genetic condition that can lead to low levels of A1AT in the lungs, causing an imbalance between A1AT and human neutrophil elastase (HNE), its preferential target. This can predispose those affected to emphysema, often in the 3rd or 4th decade of life. Certain genetic mutations can also lead to an accumulation of A1AT in the liver, potentially leading to cirrhosis as well as early-onset emphysema. Approximately 100,000 people in the United States are estimated to be affected by A1AD, but it has been estimated that only about 10,000 have been diagnosed. Across the globe, it is estimated that 116 million people worldwide are carriers of the S or Z forms, and another 1.1 million are estimated to have A1AD. Currently, no cure exists, and current approaches for diagnosis are insufficient as illustrated by the fact that A1AD is underdiagnosed and diagnosis is often delayed.[2] More than 120 mutations have been recognized with the two most prevalent being referred to as S and Z in contrast to the M form. These letter designations stem from where the protein migrates during isoelectric focusing, with the M form stopping in the middle and the Z form migrating the slowest of any of the mutations.[2] Further, it has been shown that A1AT can be oxidized at the active site which reduces its ability to associate with HNE up to 2000 fold.[3] With these issues, a new method of diagnosis is being developed. Quartz crystal microbalance approaches are utilized in development of fuel cell technologies, aerosol particle sizing instruments, and in other systems exploiting aspects of electrochemistry and mass changes on highly sensitive crystals. A1AT has both electrostatic and electrochemical properties. [ 4 ] The intention of this project is to utilize the A1AT redox signature combined with substrate adsorption to develop a dual detection method. Substrate adsorption will be measured in tandem with an Electrochemical Quartz Crystal Microbalance (EQCM) system where HNE is attached to the Au electrode, and a buffered solution of A1AT is flowed over the top of the electrode. The frequency of vibration of the crystal, which can be inversely correlated to the change in mass over time, is measured over time. This change in mass along with electrochemical measures over time can be used to correlate to the kinetics of the inhibition of A1AT. Any differences seen between the M form of A1AT and other forms of A1AT, both on a mass and kinetic basis, might allow for the distinction of multiple forms. Grieshaber, D., MacKenzie, R., Voeroes, J., & Reimhult, E. (2008). Electrochemical biosensors-sensor principles and architectures. Sensors, (January), 1400–1458. Retrieved from http://www.mdpi.com/1424-8220/8/3/1400/htmAmerican Thoracic Society/European Respiratory Society statement: standards for the diagnosis and management of individuals with alpha-1 antitrypsin deficiency. (2003). American Journal of Respiratory and Critical Care Medicine, 168(7), 818–900. http://doi.org/10.1164/rccm.168.7.818Beatty, K., Bieth, J., & Travis, J. (1980). Kinetics of association of serine proteinases with native and oxidized alpha-1-proteinase inhibitor and alpha-1-antichymotrypsin. The Journal of Biological Chemistry, 255(9), 3931–4. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/6989830Fadiel, A., K.D. Eichenbaum, A. Hamza, O. Tan, H.H. Lee, and F. Naftolin, 'Modern pathology: protein mis-folding and mis-processing in complex disease', Curr. Protein Pept. Sci., 2007, 8, 29.

Application of the Wedge Scheme to Explain Quinone-Phenol Electrochemical Systems

Schemes involving chemical reactions, usually hydrogen bonding or proton transfer, and electron transfers have been used for decades to describe electrochemical process important to biology,1 medicine,2,3 and fundamental chemistry.4 These schemes often take advantage of the fact that many of them are thermodynamic cycles, of “square schemes,” which allow us to determine the free energy of reaction of any one step if we know the values for the other steps. The fact that such systems appear so often in organic electrochemistry is due to the twin reasons that (1) adding or subtracting electrons from organic molecules often perturbs the molecule enough to cause another reaction, thus giving rise to such schemes, and (2) voltammetry is a convenient means of determining reaction thermodynamics. Recently, two of these squares have been combined into a 3-dimensional “wedge” scheme in order to explain the electrochemistry of an electroactive urea.5,6 Here we report the use of this wedge scheme to explain the voltammetry of the quinone-phenol system. This system is very important because it is present in the electron transport chains present in both chloroplasts and mitochondria and is therefore an important area of study for both pharmaceuticals and energy transduction. Cyclic voltammograms of para-quinones usually have just two waves that correspond to reduction to a radical anion and then to the dianion: Q <=> Q- <=> Q2-. With the addition of naphthol, one new reversible wave appears at a potential intermediate of the old two, and one new oxidation peak appears at a potential positive of all the rest. These are very broad at all concentrations of naphthol and at the higher concentrations of naphthol the reduction wave associated with Q <=> Q- also increases. The broadness here could indicate a proton coupled electron transfer (PCET) within a hydrogen bonded complex between Q- and the naphthol which reversibly breaks apart, in which case the proton either ends up on the quinone, which broadens the wave positive, or on the naphthol, which broadens the wave negative. The potentials of the new peaks do not correspond to a pure hydrogen bonded complex because the shift is too large as compared to a related hydrogen bonded complex with 2 hydrogen bonds rather than one.7 The reversibility of the peaks at a range of scan rates argues against a pure PCET mechanism because the reverse wave would be oxidation of a protonated quinone, which should occur at a much shifted potential. Fitted digital simulations, concentration dependence experiments, and scan rate dependence experiments will be discussed. 1. Thayer, W. S. and Hinkle, P. C. The Journal of Biological Chemistry (1975) vol 250, pp 5330-5335. 2. Rao, Gopalakrishna M.; Lown, J. William; and Plambeck, James A. Journal of the Electrochemical Society (1978) vol 175, iss 4, pp 540-543. 3. Andres, Theresa; Eckmann, Lars; and Smith, Diane K. Electrochimica Acta vol 92, pp 257-268. 4. Bonin, Julien; Costentin, Cyrille; Louault, Cyril; Robert, Marc; and Saveant, Jean-Michel. Journal of the American Chemical Society (2011) vol 133, iss 17, pp 6668-6674. 5. Clare, Laurie A.; Pham, An T.; Magdaleno, Francine; Acosta, Jaqueline; Woods, Jessica E.; Cooksy, Andrew L.; and Smith, Diane K. Journal of the American Chemical Society (2013) vol 135, iss 50, pp 18930-18941. 6. Staley, Patrick A.; Newell, Christina; Pullman, David; and Smith, Diane K. Analytical Chemistry (2014) vol 86, iss 21, pp 10917-10924. 7. Ge, Yu; Lilienthal, Ronald R.; and Smith, Diane K. Journal of the American Chemical Society (1996) vol 118, iss 16, pp 3976-3977.

On Credibility, Clarity, and Compliance

On Credibility, Clarity, and Compliance

The citation evolution law of papers published in the same year but different month

To explore the citation evolution of papers published in the same year but different month, we selected papers from a discipline (physical geography), a subject (diabetes: endocrine and metabolism) and a journal (Journal of Biological Chemistry) published in 2005 as research objects. These papers were divided into six groups according to the difference in publication month, and we analyzed citations to these papers for the 9 years after publication. The results showed that within 5 years after papers from physical geography were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); after that, the differences were not statistically significant. Within 5 years after papers from diabetes (endocrine and metabolism) were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Within 7 years after papers from the Journal of Biological Chemistry were published, the overall differences in citations of papers in different groups were statistically significant (P < 0.05); thereafter, the differences were not statistically significant. Citations of papers followed the same pattern irrespective of discipline, subject or journal: citations of papers published in the same year but different month were obviously different in the first few publishing years, but as time went on, only the difference in publication month in a calendar year did not affect the papers' longer-term citation.

A web repository of research literature assessment questions to promote student learning and acquisition of scientific reasoning and inquiry skills necessary for both the MCAT2015 and ASBMB certification

An increasing emphasis is being placed on scientific inquiry and reasoning skills in both the new MCAT2015 and in new student learning goals and objectives developed by the ASBMB for student certification. This comes as both organizations are moving from recommending required courses to recommending acquisition of competencies and skills by students. For the new MCAT2015, students must have a diverse knowledge of concepts/ideas from the biological/ physical sciences and apply this knowledge to problem solving, assessing experimental design/methodology, and using data and statistical reasoning. An optimal approach to prepare students for this new emphasis is to have them analyze data and draw conclusions from research papers. These changes will require faculty to use more research‐literature based question to assess the students' acquisition of these higher level Bloom's learning skills. To facilitate this change, I have developed a model for the creation of a web‐based collection of assessment questions derived from the research literature. Model assessment questions were created using data, figures and tables derived from The Journal of Biological Chemistry. Questions are targeted to assess the broadly overlapping learning goals recently articulated by the ASBMB for programs accredited in Biochemistry and Molecular Biology, and the learning competencies developed by the Association of American Medical Colleges for the new MCAT2015. Faculty would use, contribute to and help peer‐review the proposed collection. Students would use it to gain skills in understanding and evaluating research design and findings.

Medical marijuana: hints of headway? Despite a conflicted regulatory landscape, support for medical marijuana is growing amid increasing evidence of potential benefits.

Medical marijuana: hints of headway? Despite a conflicted regulatory landscape, support for medical marijuana is growing amid increasing evidence of potential benefits.

Study of the impact of Tau phosphorylation on its internalization and processing in cultured neuronal cells

Study of the impact of Tau phosphorylation on its internalization and processing in cultured neuronal cells

Editorial introductions

Editorial introductions

Synthetic Biology in Action: Developing a Drug Against MDR-TB.

The amalgamation of the research efforts of biologists, chemists and geneticists led by scientists at the Department of Zoology, University of Delhi has resulted in the development of a novel rifamycin derivative; 24-desmethylrifampicin, which is highly effective against multi-drug resistant (MDR) strains of Mycobacterium tuberculosis. The production of rifamycin analogue was facilitated by genetic-synthetic strategies that have opened an interdisciplinary route for the development of more such rifamycin analogues aiming at a better therapeutic potential. The results of this painstaking effort of nearly 25years of a team of students and scientists led by Professor Rup Lal have been recently published in the Journal of Biological Chemistry (www.jbc.org/content/289/30/21142.long). This strategy can now find applications for developing newer rifamycin analogues that can be harnessed to overcome the problem of MDR, extensively drug resistant (XDR) and totally drug resistant (TDR) M. tuberculosis.

Abstract 5287: Identification of metadherin in a complex with RACK1/PP2A in mammary epithelial cells

Abstract Protein Phosphatase 2A (PP2A) is a major serine/threonine phosphatase in cells. It consists of a catalytic (C), structural (A) and regulatory/variable B-type subunits. PP2A has a critical role to play in homeostasis where it functions as a tumour suppressor. Changes in the activity of PP2A have a direct role in maintaining the transformed phenotype in cancer. However, the mechanism of action of PP2A during this process is poorly understood. Our understanding is limited because of the complex nature of PP2A holoenzyme assembly, and because it acts through a wide variety of signalling pathways. We have identified the scaffolding protein RACK1 as a PP2A interacting protein and we showed that RACK1 regulates PP2A activity to mediate crosstalk between growth factor and adhesion signalling by an IGF-I-independent mechanism(1, 2) . Our hypothesis is that RACK1 plays a critical role in determining how PP2A functions in signalling pathways. Using a series of truncation mutations and peptide array technology, we have identified and mapped the binding sites between RACK1 and the catalytic subunit of PP2A. Using a series of specific point mutations of these PP2A sites, we show that the RACK1/PP2A interaction is critical to maintain PP2A activity. Disruption of the RACK1/PP2A interaction has dramatic consequences for cell adhesion, proliferation and migration in MCF-7 cells. Our hypothesis is that RACK1 regulates the cellular distribution of PP2A and scaffolds PP2A to a specific subset of cellular targets. Using 3D in vitro breast cancer models and mass spectroscopy approaches, we have identified several proteins that interact with the RACK1/PP2A complex. One of these proteins, Metadherin has been shown to play a role in drug resistance(3). It has also been linked to the progression of many cancers(4). Using a series of novel approaches we have mapped the Metadherin interaction site on RACK1 and PP2A and confirmed that RACK1 and Metadherin colocalise at the cell membrane. Overexpression of Metadherin promotes IGF-I-mediated cell migration and invasion. Taken together, our data suggest that RACK1 scaffolds PP2A to Metadherin where it regulates Metadherin activity and cell migration in breast cancer. 1. Kiely, PA., et al. “Tyrosine 302 in RACK1 is essential for insulin-like growth factor-I-mediated competitive binding of PP2A and β1 integrin and for tumor cell proliferation and migration.” Journal of Biological Chemistry 283.34 (2008): 22952-22961. 2. Kiely, PA., et al. “Insulin-like growth factor I controls a mutually exclusive association of RACK1 with protein phosphatase 2A and β1 integrin to promote cell migration.” Molecular and cellular biology 26.11 (2006): 4041-4051. 3. Wei, Yong, Guohong Hu, and Yibin Kang. “Metadherin as a link between metastasis and chemoresistance.” Cell Cycle 8.14 (2009): 2131-2137. 4. Brown, DM., and Erkki R. “Metadherin, a cell surface protein in breast tumors that mediates lung metastasis.” Cancer cell 5.4 (2004): 365-374. Citation Format: Maeve L. Kiely, Rosemary O'Connor, Patrick A. Kiely. Identification of metadherin in a complex with RACK1/PP2A in mammary epithelial cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5287. doi:10.1158/1538-7445.AM2014-5287