50

AT#507 - Travel to Buffalo, New York

Hear about travel to Buffalo, New York as the Amateur Traveler talks to Larissa Milne from changesinlongitude.com about why she fell in love with this significant American city.




50

AT#508 - Travel to Dallas, Texas

Hear about travel to Dallas, Texas  as the Amateur Traveler talks to Penny Sadler from adventuresofacarryon.com about her hometown of Dallas, Texas. Penny tells us why we might be surprised at all Dallas has to offer and why we should leave our cowboy hats at home.




50

AT#509 - Cruising to Cuba

Hear about cruising to Cuba as the Amateur Traveler talks again to Dave Grenewetzki about his trip on a ship based People to People trip to Cuba.




50

AT#550 - Travel to Tokyo, Japan

Hear about travel to Tokyo as the Amateur Traveler talks to family travel blogger / podcaster Jason Andrew Jenkins from AnEpicEducation.com about a city he called home for 13 years.




50

AT#550 - Travel to Tokyo, Japan (replay)

Hear about travel to Tokyo as the Amateur Traveler talks to family travel blogger / podcaster Jason Andrew Jenkins from AnEpicEducation.com about a city he called home for 13 years.




50

AT#650 - Travel to Rajasthan, India

Hear about travel to the northern India state of Rajasthan as the Amateur Traveler talks to Dr Pankaj Jain about his native region.




50

Newsroom: TikTok to Surpass 50 Million Users in US by 2021

More than 20% of social users will use TikTok this year February 27, 2020 (New York, NY) – Since launching in the US in 2017, social video app TikTok has […]




50

Mechanistic insights explain the transforming potential of the T507K substitution in the protein-tyrosine phosphatase SHP2 [Signal Transduction]

The protein-tyrosine phosphatase SHP2 is an allosteric enzyme critical for cellular events downstream of growth factor receptors. Mutations in the SHP2 gene have been linked to many different types of human diseases, including developmental disorders, leukemia, and solid tumors. Unlike most SHP2-activating mutations, the T507K substitution in SHP2 is unique in that it exhibits oncogenic Ras-like transforming activity. However, the biochemical basis of how the SHP2/T507K variant elicits transformation remains unclear. By combining kinetic and biophysical methods, X-ray crystallography, and molecular modeling, as well as using cell biology approaches, here we uncovered that the T507K substitution alters both SHP2 substrate specificity and its allosteric regulatory mechanism. We found that although SHP2/T507K exists in the closed, autoinhibited conformation similar to the WT enzyme, the interactions between its N-SH2 and protein-tyrosine phosphatase domains are weakened such that SHP2/T507K possesses a higher affinity for the scaffolding protein Grb2-associated binding protein 1 (Gab1). We also discovered that the T507K substitution alters the structure of the SHP2 active site, resulting in a change in SHP2 substrate preference for Sprouty1, a known negative regulator of Ras signaling and a potential tumor suppressor. Our results suggest that SHP2/T507K's shift in substrate specificity coupled with its preferential association of SHP2/T507K with Gab1 enable the mutant SHP2 to more efficiently dephosphorylate Sprouty1 at pTyr-53. This dephosphorylation hyperactivates Ras signaling, which is likely responsible for SHP2/T507K's Ras-like transforming activity.




50

Chatham House is ranked in the Inclusive Top 50 UK Employers List

5 December 2017

The newly published Inclusive Top 50 UK Employers showcases leading organizations working across all strands of diversity.

In recognition of Chatham House’s continued dedication to workplace diversity, the institute has been listed in the Inclusive Top 50 UK Employers List – a definitive ranking of UK-based organizations that promote inclusion across all protected characteristics, throughout each level of employment within an organization.

Powered by the Excellence in Diversity Awards, the Inclusive Top 50 UK Employers recognizes the organizations that demonstrate the promotion of all strands of diversity including age, disability, gender, LGBT, race, faith and religion.

Complied by a dedicated panel of judges, the list has been collated based on each organization’s performance in a range of areas within the diversity arena. Organizations featured have provided sufficient evidence on an amalgam of topics including recruitment procedures, training and a host of diversity related initiatives.

The Inclusive Top 50 UK Employers List, in partnership with recruitment specialists Rullion, recognizes the outstanding efforts of organizations that have begun their journey to attracting and retaining a truly diverse workforce, achieving equality, diversity and inclusion in its purest form.

Lisa O’Daly, Director of Human Resources, Chatham House, said: ‘I am delighted that Chatham House has been included in the Inclusive Top 50 UK Employers List. This is just really the beginning of our journey to diversity and inclusion and is a recognition of the collective efforts of our staff which is changing Chatham House for the better.’

‘The UK companies on the list are showing by their actions that they are integrating what they believe into how they operate creating an inclusive culture, which begins at the very top of the organization,’ said Donna Herdsman, EMEA Partnership Manager, Rullion. 




50

The cytochrome P450 enzyme CYP24A1 increases proliferation of mutant KRAS-dependent lung adenocarcinoma independent of its catalytic activity [Cell Biology]

We previously reported that overexpression of cytochrome P450 family 24 subfamily A member 1 (CYP24A1) increases lung cancer cell proliferation by activating RAS signaling and that CYP24A1 knockdown inhibits tumor growth. However, the mechanism of CYP24A1-mediated cancer cell proliferation remains unclear. Here, we conducted cell synchronization and biochemical experiments in lung adenocarcinoma cells, revealing a link between CYP24A1 and anaphase-promoting complex (APC), a key cell cycle regulator. We demonstrate that CYP24A1 expression is cell cycle–dependent; it was higher in the G2-M phase and diminished upon G1 entry. CYP24A1 has a functional destruction box (D-box) motif that allows binding with two APC adaptors, CDC20-homologue 1 (CDH1) and cell division cycle 20 (CDC20). Unlike other APC substrates, however, CYP24A1 acted as a pseudo-substrate, inhibiting CDH1 activity and promoting mitotic progression. Conversely, overexpression of a CYP24A1 D-box mutant compromised CDH1 binding, allowing CDH1 hyperactivation, thereby hastening degradation of its substrates cyclin B1 and CDC20, and accumulation of the CDC20 substrate p21, prolonging mitotic exit. These activities also occurred with a CYP24A1 isoform 2 lacking the catalytic cysteine (Cys-462), suggesting that CYP24A1's oncogenic potential is independent of its catalytic activity. CYP24A1 degradation reduced clonogenic survival of mutant KRAS-driven lung cancer cells, and calcitriol treatment increased CYP24A1 levels and tumor burden in Lsl-KRASG12D mice. These results disclose a catalytic activity-independent growth-promoting role of CYP24A1 in mutant KRAS-driven lung cancer. This suggests that CYP24A1 could be therapeutically targeted in lung cancers in which its expression is high.




50

Mechanistic insights explain the transforming potential of the T507K substitution in the protein-tyrosine phosphatase SHP2 [Signal Transduction]

The protein-tyrosine phosphatase SHP2 is an allosteric enzyme critical for cellular events downstream of growth factor receptors. Mutations in the SHP2 gene have been linked to many different types of human diseases, including developmental disorders, leukemia, and solid tumors. Unlike most SHP2-activating mutations, the T507K substitution in SHP2 is unique in that it exhibits oncogenic Ras-like transforming activity. However, the biochemical basis of how the SHP2/T507K variant elicits transformation remains unclear. By combining kinetic and biophysical methods, X-ray crystallography, and molecular modeling, as well as using cell biology approaches, here we uncovered that the T507K substitution alters both SHP2 substrate specificity and its allosteric regulatory mechanism. We found that although SHP2/T507K exists in the closed, autoinhibited conformation similar to the WT enzyme, the interactions between its N-SH2 and protein-tyrosine phosphatase domains are weakened such that SHP2/T507K possesses a higher affinity for the scaffolding protein Grb2-associated binding protein 1 (Gab1). We also discovered that the T507K substitution alters the structure of the SHP2 active site, resulting in a change in SHP2 substrate preference for Sprouty1, a known negative regulator of Ras signaling and a potential tumor suppressor. Our results suggest that SHP2/T507K's shift in substrate specificity coupled with its preferential association of SHP2/T507K with Gab1 enable the mutant SHP2 to more efficiently dephosphorylate Sprouty1 at pTyr-53. This dephosphorylation hyperactivates Ras signaling, which is likely responsible for SHP2/T507K's Ras-like transforming activity.




50

Structure of an ancestral mammalian family 1B1 cytochrome P450 with increased thermostability [Enzymology]

Mammalian cytochrome P450 enzymes often metabolize many pharmaceuticals and other xenobiotics, a feature that is valuable in a biotechnology setting. However, extant P450 enzymes are typically relatively unstable, with T50 values of ∼30–40 °C. Reconstructed ancestral cytochrome P450 enzymes tend to have variable substrate selectivity compared with related extant forms, but they also have higher thermostability and therefore may be excellent tools for commercial biosynthesis of important intermediates, final drug molecules, or drug metabolites. The mammalian ancestor of the cytochrome P450 1B subfamily was herein characterized structurally and functionally, revealing differences from the extant human CYP1B1 in ligand binding, metabolism, and potential molecular contributors to its thermostability. Whereas extant human CYP1B1 has one molecule of α-naphthoflavone in a closed active site, we observed that subtle amino acid substitutions outside the active site in the ancestor CYP1B enzyme yielded an open active site with four ligand copies. A structure of the ancestor with 17β-estradiol revealed only one molecule in the active site, which still had the same open conformation. Detailed comparisons between the extant and ancestor forms revealed increases in electrostatic and aromatic interactions between distinct secondary structure elements in the ancestral forms that may contribute to their thermostability. To the best of our knowledge, this represents the first structural evaluation of a reconstructed ancestral cytochrome P450, revealing key features that appear to contribute to its thermostability.




50

Cytochrome P450 and arachidonic acid bioactivation: molecular and functional properties of the arachidonate monooxygenase

Jorge H. Capdevila
Feb 1, 2000; 41:163-181
Reviews




50

Undercurrents: Episode 50 - The Coronavirus Communications Crisis, and Justice in Myanmar





50

The Executive Director's Statement to the 150th Meeting of the Committee of Permanent Representatives

In these unusual and tragic times, I am indeed grateful that we are able to connect virtually to continue the business of environmental governance. While the efforts of all your capitals are correctly focused on preventing human suffering, as parts of the world move slowly towards recovery, the environmental agenda remains one of our most powerful insurance policies in preventing future global pandemics like COVID-19.




50

$50 Logo Contest - Paypal - 5 Days




50

$150 logo design contest (top 3 paid) E-commerce brand (7 days)




50

NHS promised £250m for AI: where will the money go?

Healthcare insiders explain their hopes and fears for the government's plan to create a new AI lab within NHSX




50

CBD News: Message of the Executive Secretary, Dr. Ahmed Djoghlaf, on the occasion of the Technical Workshop on Protected Areas in the Amazon, 14-16 July 2008, Amacayacú National Park, Colombia.




50

CBD Press Release: Celebrating the 150th anniversary of On the Origin of Species and the launch of the UK partnership supporting Biodiversity is Life - the International Year of Biodiversity 2010.




50

CBD News: Statement by Mr. Ahmed Djoghlaf, Executive Secretary of the Convention on Biological Diversity, on the occasion of the Interacademy Panel Biodiversity Conference: Integrating Ecosystem Services into Biodiversity Management, Celebrating 350 Years




50

CBD Communiqué: 500 Tunisian Schools to Join the Green Wave for Biodiversity.




50

CBD News: 50th-51st edition of the Quarterly Report on the Administration of the Convention on Biological Diversity (July-December 2010)




50

CBD Communiqué: Hyderabad, 27 September 2012 - Some 2000 delegates from more than 150 countries will convene this coming Monday in Hyderabad, India, for the sixth meeting of the Conference of the Parties serving as the meeting of the Parties to the C




50

CBD News: In its inaugural remarks at the High-Level Segment of COP 11, Dr. Manmohan Singh, Prime Minister of India, launched the Hyderabad Pledge by announcing that the Government of India has earmarked US$ 50 million to strengthen the institutional mech




50

CBD News: The theme for this year's International Women's Day, "Planet 50-50 by 2030: Step it up for Gender Equality", is well-aligned with the ambitious Agenda 2030 for Sustainable Development, which integrates gender equality and women




50

CBD News: By 2050, an estimated 6.3 billion people will inhabit the world's towns and cities - an increase of 3.5 billion from 2010.




50

CBD News: Every year, we use some 500 billion plastic bags. Every year, as much as 13 million tons of plastic finds its way into the ocean. Every year, 17 million barrels of oil are used to produce plastic.




50

CBD Notification SCBD/SSSF/AS/JS/TMC/VA/88505 (2019-106): Survey on Progress in Implementation of the 2015-2020 Gender Plan of Action




50

Structures of the MHC-I molecule BF2*1501 disclose the preferred presentation of an H5N1 virus-derived epitope [Protein Structure and Folding]

Lethal infections by strains of the highly-pathogenic avian influenza virus (HPAIV) H5N1 pose serious threats to both the poultry industry and public health worldwide. A lack of confirmed HPAIV epitopes recognized by cytotoxic T lymphocytes (CTLs) has hindered the utilization of CD8+ T-cell–mediated immunity and has precluded the development of effectively diversified epitope-based vaccination approaches. In particular, an HPAIV H5N1 CTL-recognized epitope based on the peptide MHC-I–β2m (pMHC-I) complex has not yet been designed. Here, screening a collection of selected peptides of several HPAIV strains against a specific pathogen-free pMHC-I (pBF2*1501), we identified a highly-conserved HPAIV H5N1 CTL epitope, named HPAIV–PA123–130. We determined the structure of the BF2*1501–PA123–130 complex at 2.1 Å resolution to elucidate the molecular mechanisms of a preferential presentation of the highly-conserved PA123–130 epitope in the chicken B15 lineage. Conformational characteristics of the PA123–130 epitope with a protruding Tyr-7 residue indicated that this epitope has great potential to be recognized by specific TCRs. Moreover, significantly increased numbers of CD8+ T cells specific for the HPAIV–PA123–130 epitope in peptide-immunized chickens indicated that a repertoire of CD8+ T cells can specifically respond to this epitope. We anticipate that the identification and structural characterization of the PA123–130 epitope reported here could enable further studies of CTL immunity against HPAIV H5N1. Such studies may aid in the development of vaccine development strategies using well-conserved internal viral antigens in chickens.




50

Structure of an ancestral mammalian family 1B1 cytochrome P450 with increased thermostability [Enzymology]

Mammalian cytochrome P450 enzymes often metabolize many pharmaceuticals and other xenobiotics, a feature that is valuable in a biotechnology setting. However, extant P450 enzymes are typically relatively unstable, with T50 values of ∼30–40 °C. Reconstructed ancestral cytochrome P450 enzymes tend to have variable substrate selectivity compared with related extant forms, but they also have higher thermostability and therefore may be excellent tools for commercial biosynthesis of important intermediates, final drug molecules, or drug metabolites. The mammalian ancestor of the cytochrome P450 1B subfamily was herein characterized structurally and functionally, revealing differences from the extant human CYP1B1 in ligand binding, metabolism, and potential molecular contributors to its thermostability. Whereas extant human CYP1B1 has one molecule of α-naphthoflavone in a closed active site, we observed that subtle amino acid substitutions outside the active site in the ancestor CYP1B enzyme yielded an open active site with four ligand copies. A structure of the ancestor with 17β-estradiol revealed only one molecule in the active site, which still had the same open conformation. Detailed comparisons between the extant and ancestor forms revealed increases in electrostatic and aromatic interactions between distinct secondary structure elements in the ancestral forms that may contribute to their thermostability. To the best of our knowledge, this represents the first structural evaluation of a reconstructed ancestral cytochrome P450, revealing key features that appear to contribute to its thermostability.




50

Mechanistic insights explain the transforming potential of the T507K substitution in the protein-tyrosine phosphatase SHP2 [Signal Transduction]

The protein-tyrosine phosphatase SHP2 is an allosteric enzyme critical for cellular events downstream of growth factor receptors. Mutations in the SHP2 gene have been linked to many different types of human diseases, including developmental disorders, leukemia, and solid tumors. Unlike most SHP2-activating mutations, the T507K substitution in SHP2 is unique in that it exhibits oncogenic Ras-like transforming activity. However, the biochemical basis of how the SHP2/T507K variant elicits transformation remains unclear. By combining kinetic and biophysical methods, X-ray crystallography, and molecular modeling, as well as using cell biology approaches, here we uncovered that the T507K substitution alters both SHP2 substrate specificity and its allosteric regulatory mechanism. We found that although SHP2/T507K exists in the closed, autoinhibited conformation similar to the WT enzyme, the interactions between its N-SH2 and protein-tyrosine phosphatase domains are weakened such that SHP2/T507K possesses a higher affinity for the scaffolding protein Grb2-associated binding protein 1 (Gab1). We also discovered that the T507K substitution alters the structure of the SHP2 active site, resulting in a change in SHP2 substrate preference for Sprouty1, a known negative regulator of Ras signaling and a potential tumor suppressor. Our results suggest that SHP2/T507K's shift in substrate specificity coupled with its preferential association of SHP2/T507K with Gab1 enable the mutant SHP2 to more efficiently dephosphorylate Sprouty1 at pTyr-53. This dephosphorylation hyperactivates Ras signaling, which is likely responsible for SHP2/T507K's Ras-like transforming activity.




50

The cytochrome P450 enzyme CYP24A1 increases proliferation of mutant KRAS-dependent lung adenocarcinoma independent of its catalytic activity [Cell Biology]

We previously reported that overexpression of cytochrome P450 family 24 subfamily A member 1 (CYP24A1) increases lung cancer cell proliferation by activating RAS signaling and that CYP24A1 knockdown inhibits tumor growth. However, the mechanism of CYP24A1-mediated cancer cell proliferation remains unclear. Here, we conducted cell synchronization and biochemical experiments in lung adenocarcinoma cells, revealing a link between CYP24A1 and anaphase-promoting complex (APC), a key cell cycle regulator. We demonstrate that CYP24A1 expression is cell cycle–dependent; it was higher in the G2-M phase and diminished upon G1 entry. CYP24A1 has a functional destruction box (D-box) motif that allows binding with two APC adaptors, CDC20-homologue 1 (CDH1) and cell division cycle 20 (CDC20). Unlike other APC substrates, however, CYP24A1 acted as a pseudo-substrate, inhibiting CDH1 activity and promoting mitotic progression. Conversely, overexpression of a CYP24A1 D-box mutant compromised CDH1 binding, allowing CDH1 hyperactivation, thereby hastening degradation of its substrates cyclin B1 and CDC20, and accumulation of the CDC20 substrate p21, prolonging mitotic exit. These activities also occurred with a CYP24A1 isoform 2 lacking the catalytic cysteine (Cys-462), suggesting that CYP24A1's oncogenic potential is independent of its catalytic activity. CYP24A1 degradation reduced clonogenic survival of mutant KRAS-driven lung cancer cells, and calcitriol treatment increased CYP24A1 levels and tumor burden in Lsl-KRASG12D mice. These results disclose a catalytic activity-independent growth-promoting role of CYP24A1 in mutant KRAS-driven lung cancer. This suggests that CYP24A1 could be therapeutically targeted in lung cancers in which its expression is high.




50

Lars Hernquist and Volker Springel receive $500,000 Gruber Cosmology Prize

(Yale University) The 2020 Gruber Cosmology Prize recognizes Lars Hernquist, Center for Astrophysics | Harvard & Smithsonian, and Volker Springel, Max Planck Institute for Astrophysics, for their defining contributions to cosmological simulations, a method that tests existing theories of, and inspires new investigations into, the formation of structures at every scale from stars to galaxies to the universe itself.




50

Long term follow-up and outcomes of re-treatment in an expanded 50 patient single-center phase II prospective trial of Lutetium-177 (177Lu) PSMA-617 theranostics in metastatic castrate-resistant prostate cancer

Objectives: Lutetium-177 (177Lu)-PSMA-617 (LuPSMA) is a radioligand with high affinity for prostate specific membrane antigen (PSMA) enabling targeted beta-irradiation of prostate cancer. We have previously reported favorable activity with low toxicity in a prospective phase II trial involving 30 men with metastatic castrate-resistant prostate cancer (mCRPC). We now report their longer-term outcomes including a 20 patient extension cohort and outcomes of subsequent systemic treatments following completion of trial therapy. Methods: 50 patients with PSMA-avid mCRPC who had progressed after standard therapies received up to 4 cycles of LuPSMA every 6 weeks. Endpoints included PSA response (PCWG2), toxicity (CTCAE v4.03), imaging response, patient-reported health-related quality of life (QoL), progression-free and overall survival. We also describe, as a novel finding, outcomes of men who subsequently progressed and had further systemic therapies, including LuPSMA. Results: 75 men were screened to identify 50 patients eligible for treatment. Adverse prognostic features of the cohort included short median PSA doubling time (2.3 months) and extensive prior treatment including prior docetaxel (84%), cabazitaxel (48%), and abiraterone and/or enzalutamide (90%). The mean administered radioactivity was 7.5 GBq/cycle. PSA decline ≥ 50% was achieved in 32 of 50 patients (64%, 95% CI 50-77%), including 22 patients (44%, 95% CI 30-59%) with ≥ 80% decrease. Of 27 patients with measurable soft tissue disease, 15 (56%) achieved an objective response by RECIST 1.1. The most common toxicities attributed to LuPSMA were self-limiting G1-2 dry mouth (66%), transient G1-2 nausea (48%), G3-4 thrombocytopenia (10%) and G3 anemia (10%). Brief pain inventory severity and interference scores decreased at all time points including at the 3 month follow-up with a decrease of -1.2 (95% CI -0.5 to -1.9, P = 0.001) and 1.0 (95% CI -0.2 to -0.18, P = 0.013), respectively. At a median follow-up of 31.4 months, median OS was 13.3 months (95% CI 10.5-18.7) with a significantly longer survival of 18.4 months (95% CI 13.8-23.8) in patients achieving a PSA decline ≥ 50%. At progression following prior response, further LuPSMA was administered to 15 (30%) patients (median 2 cycles commencing 359 days from enrolment) with PSA decline ≥ 50% in 11 patients (73%). 4 of 21 patients (19%) receiving other systemic therapies upon progression experienced PSA decline ≥ 50%. There were no unexpected adverse events with LuPSMA re-treatment. Conclusion: This expanded 50 patient cohort of men with extensive prior therapy confirms our earlier report of high response rates, low toxicity and improved QoL with LuPSMA radioligand therapy. Upon progression, re-challenge LuPSMA demonstrated higher response rates than other systemic therapies.




50

Malcolm Turnbull promises $50 million reboot for troubled myGov

Takeover of troubled portal by Digital Transformation Office confirmed




50

Episode 50 - The Internet of Fiftieth Episode Special (IoFES) Anything goes, tbh

Momentous scenes as the pod celebrates its Golden Jubilee. Matt Egan is joined by some very special guests to congratulate the gang on the milestone while indulging in some points based tech quizzing. Join Chris Martin, Charlotte Jee, Dom Preston and Henry Burrell to recap questions from pods gone by with a new twist, and have a long hard think about what tech will be 50 more episodes from now. The prize? A small bronze jug. Obviously. NB. May not actually be 50 minutes, sorry.  


See acast.com/privacy for privacy and opt-out information.




50

Problem Notes for SAS®9 - 35066: When a bulk-loading process fails with "SQL*Loader 2026" error, error message appears as a warning in the SAS log

If a bulk-loading process fails when you use SAS with SAS/ACCESS Interface to Oracle, you will receive the warning: "WARNING: All or some rows were rejected/discarded.: The actual error is "SQL*Loader-2026: The load was aborted because SQL




50

Problem Notes for SAS®9 - 65031: Grid options set mappings are returned based on which option set is the first in the metadata search chain

When users are defined in multiple groups associated with grid options set mappings, the first grid option set that is returned by the metadata search chain takes precedence. Only one grid options set mapping is used




50

Problem Notes for SAS®9 - 64550: SAS Enterprise Case Management contains a cross-site scripting vulnerability in the CASE_ID parameter

Severity: Medium Description: SAS Enterprise Case Management contains a cross-site scripting vulnerability in the CASE_ID parameter. Potential Impact:




50

Uniform patch to mark 150 years of pro baseball

All 30 Major League teams will wear special "MLB 150" patches on their uniforms for the entire 2019 season in honor of the 150th anniversary of the 1869 Cincinnati Red Stockings, the first openly all-salaried professional baseball team.




50

The cytochrome P450 enzyme CYP24A1 increases proliferation of mutant KRAS-dependent lung adenocarcinoma independent of its catalytic activity [Cell Biology]

We previously reported that overexpression of cytochrome P450 family 24 subfamily A member 1 (CYP24A1) increases lung cancer cell proliferation by activating RAS signaling and that CYP24A1 knockdown inhibits tumor growth. However, the mechanism of CYP24A1-mediated cancer cell proliferation remains unclear. Here, we conducted cell synchronization and biochemical experiments in lung adenocarcinoma cells, revealing a link between CYP24A1 and anaphase-promoting complex (APC), a key cell cycle regulator. We demonstrate that CYP24A1 expression is cell cycle–dependent; it was higher in the G2-M phase and diminished upon G1 entry. CYP24A1 has a functional destruction box (D-box) motif that allows binding with two APC adaptors, CDC20-homologue 1 (CDH1) and cell division cycle 20 (CDC20). Unlike other APC substrates, however, CYP24A1 acted as a pseudo-substrate, inhibiting CDH1 activity and promoting mitotic progression. Conversely, overexpression of a CYP24A1 D-box mutant compromised CDH1 binding, allowing CDH1 hyperactivation, thereby hastening degradation of its substrates cyclin B1 and CDC20, and accumulation of the CDC20 substrate p21, prolonging mitotic exit. These activities also occurred with a CYP24A1 isoform 2 lacking the catalytic cysteine (Cys-462), suggesting that CYP24A1's oncogenic potential is independent of its catalytic activity. CYP24A1 degradation reduced clonogenic survival of mutant KRAS-driven lung cancer cells, and calcitriol treatment increased CYP24A1 levels and tumor burden in Lsl-KRASG12D mice. These results disclose a catalytic activity-independent growth-promoting role of CYP24A1 in mutant KRAS-driven lung cancer. This suggests that CYP24A1 could be therapeutically targeted in lung cancers in which its expression is high.




50

Structures of the MHC-I molecule BF2*1501 disclose the preferred presentation of an H5N1 virus-derived epitope [Protein Structure and Folding]

Lethal infections by strains of the highly-pathogenic avian influenza virus (HPAIV) H5N1 pose serious threats to both the poultry industry and public health worldwide. A lack of confirmed HPAIV epitopes recognized by cytotoxic T lymphocytes (CTLs) has hindered the utilization of CD8+ T-cell–mediated immunity and has precluded the development of effectively diversified epitope-based vaccination approaches. In particular, an HPAIV H5N1 CTL-recognized epitope based on the peptide MHC-I–β2m (pMHC-I) complex has not yet been designed. Here, screening a collection of selected peptides of several HPAIV strains against a specific pathogen-free pMHC-I (pBF2*1501), we identified a highly-conserved HPAIV H5N1 CTL epitope, named HPAIV–PA123–130. We determined the structure of the BF2*1501–PA123–130 complex at 2.1 Å resolution to elucidate the molecular mechanisms of a preferential presentation of the highly-conserved PA123–130 epitope in the chicken B15 lineage. Conformational characteristics of the PA123–130 epitope with a protruding Tyr-7 residue indicated that this epitope has great potential to be recognized by specific TCRs. Moreover, significantly increased numbers of CD8+ T cells specific for the HPAIV–PA123–130 epitope in peptide-immunized chickens indicated that a repertoire of CD8+ T cells can specifically respond to this epitope. We anticipate that the identification and structural characterization of the PA123–130 epitope reported here could enable further studies of CTL immunity against HPAIV H5N1. Such studies may aid in the development of vaccine development strategies using well-conserved internal viral antigens in chickens.




50

Structure of an ancestral mammalian family 1B1 cytochrome P450 with increased thermostability [Enzymology]

Mammalian cytochrome P450 enzymes often metabolize many pharmaceuticals and other xenobiotics, a feature that is valuable in a biotechnology setting. However, extant P450 enzymes are typically relatively unstable, with T50 values of ∼30–40 °C. Reconstructed ancestral cytochrome P450 enzymes tend to have variable substrate selectivity compared with related extant forms, but they also have higher thermostability and therefore may be excellent tools for commercial biosynthesis of important intermediates, final drug molecules, or drug metabolites. The mammalian ancestor of the cytochrome P450 1B subfamily was herein characterized structurally and functionally, revealing differences from the extant human CYP1B1 in ligand binding, metabolism, and potential molecular contributors to its thermostability. Whereas extant human CYP1B1 has one molecule of α-naphthoflavone in a closed active site, we observed that subtle amino acid substitutions outside the active site in the ancestor CYP1B enzyme yielded an open active site with four ligand copies. A structure of the ancestor with 17β-estradiol revealed only one molecule in the active site, which still had the same open conformation. Detailed comparisons between the extant and ancestor forms revealed increases in electrostatic and aromatic interactions between distinct secondary structure elements in the ancestral forms that may contribute to their thermostability. To the best of our knowledge, this represents the first structural evaluation of a reconstructed ancestral cytochrome P450, revealing key features that appear to contribute to its thermostability.




50

Uniform patch to mark 150 years of pro baseball

All 30 Major League teams will wear special "MLB 150" patches on their uniforms for the entire 2019 season in honor of the 150th anniversary of the 1869 Cincinnati Red Stockings, the first openly all-salaried professional baseball team.




50

Uniform patch to mark 150 years of pro baseball

All 30 Major League teams will wear special "MLB 150" patches on their uniforms for the entire 2019 season in honor of the 150th anniversary of the 1869 Cincinnati Red Stockings, the first openly all-salaried professional baseball team.




50

Uniform patch to mark 150 years of pro baseball

All 30 Major League teams will wear special "MLB 150" patches on their uniforms for the entire 2019 season in honor of the 150th anniversary of the 1869 Cincinnati Red Stockings, the first openly all-salaried professional baseball team.




50

Uniform patch to mark 150 years of pro baseball

All 30 Major League teams will wear special "MLB 150" patches on their uniforms for the entire 2019 season in honor of the 150th anniversary of the 1869 Cincinnati Red Stockings, the first openly all-salaried professional baseball team.




50

NCEP-Defined Metabolic Syndrome, Diabetes, and Prevalence of Coronary Heart Disease Among NHANES III Participants Age 50 Years and Older

Charles M. Alexander
May 1, 2003; 52:1210-1214
Complications