Methods, devices and system are provided. One method includes capturing activity data associated with activity of a user via a device. The activity data is captured over time, and the activity data is quantifiable by a plurality of metrics. The method includes storing the activity data in storage of the device and, from time to time, connecting the device with a computing device over a wireless communication link. The method defines using a first transfer rate for transferring activity data captured and stored over a period of time. The first transfer rate is used following startup of an activity tracking application on the computing device The method also defines using a second transfer rate for transferring activity data from the device to the computing device for display of the activity data in substantial-real time on the computing device.

According to one embodiment, a first gene encodes a reporter protein. The first gene is disposed at the downstream of the gene promoter. A second gene is disposed at the downstream of the gene promoter and encodes a replication origin-binding protein. An internal ribosome entry site is disposed between the first gene and the second gene. The transcription termination signal sequence encodes a signal for terminating the transcription of the first gene and the second gene. A replication origin sequence is recognized by the replication origin-binding protein.

The activity monitor (100) includes a basic information acquisition unit (20) that accepts input of basic physical information (BA) of the user's body, a target information acquisition unit (30) that accepts input of the user's target physical expenditure (CS), an activity pattern acquisition unit (40) that acquires pattern information indicating the user's intent on the activity amount (AM), and a target activity calculation unit (50) that determines a target activity amount (TA) on the basis of the basic physical information (BA), the target physical expenditure (CS), and the pattern information acquired by the activity pattern acquisition unit (40).

The invention relates to CO2 capturing binder with an amortized environmental cost, the method of manufacture thereof by means of selecting, purifying and optimizing the carbide lime paste for use as a cementing material, and aggregates for the manufacture of lime paints and slurries, stuccos, mortars and concretes having multiple applications in the construction industry, in architectural restoration, in public works and land conditioning, object of the present invention. It is basically characterized in that the raw material is the residue in the form of sludge generated in the industrial manufacture of acetylene (C2H2) from calcium carbide (CaC2) the fundamental component of which is calcium hydroxide (Ca(OH)2) in highly reactive nanometric formations treated in a specific manner according to the invention.

A self-adhesive activity paper applicator dispenses a strip of paper from an internal roll directly onto a wall and then cuts it to length. The activity paper comprises pre-applied strips of temporary pressure-sensitive adhesive, beneficially having preprinted images. The applicator covers part of a wall to allow a child to color or draw upon the paper. When the child is done drawing the activity paper can be removed without damaging wall. The applicator has a pair of handles and a bottom wheel that facilitates accurate and level deployment of paper. The applicator may be disassembled to refill the paper roll.

Methods and systems that facilitate the generation, presentation, and adaptation of an anchored information bar, associated with a guided activity floorplan or wizard, in support of assisting users as they complete the different steps of a complex task as the user employs software applications (and associated user interfaces) on their devices to go about their different activities.

An activity and storage bag is includes a central compartment for holding one or more removable objects. The central compartment has an inner surface that is water-resistant and an outer surface. The activity and storage bag further includes a wallet attached to the outer surface of the central compartment for storing wallet items. The wallet includes an external flap that folds out from and attaches back with an internal flap that is connected to the outer surface of the central compartment. The activity and storage bag further includes one or more side pockets attached to the outer surface of the central compartment adjacent to the wallet.

This invention relates to novel monoclonal antibodies that specifically bind to the alpha-folate receptor. In some embodiments, the antibodies inhibit a biological activity of folate receptor-α (FR-α). The antibodies are useful in the treatment of certain cancers, particularly cancers that have increased cell surface expression of the alpha-folate receptor (“FR-α”), such as ovarian, breast, renal, colorectal, lung, endometrial, or brain cancer. The invention also relates to cells expressing the monoclonal antibodies, antibody derivatives, such as chimeric and humanized monoclonal antibodies, antibody fragments, and methods of detecting and treating cancer using the antibodies, derivatives, and fragments.

In one embodiment information regarding device activity of first subscriber to a transportation service is received. A backend server determines independent of a pending transportation request from the first passenger and based at least on the information regarding the device activity of the first subscriber, to send a driver towards a location based on the location of the first subscriber.

An internal combustion engine includes a first cylinder having an intake valve in fluid communication with an intake manifold, and a second cylinder having an exhaust valve in fluid communication with an exhaust manifold. A transfer passage fluidly connects the first cylinder with the second cylinder. A first fuel injector is configured to provide a first fuel to the first cylinder, and a second fuel injector is configured to provide a second fuel to the second cylinder. The first cylinder operates, at times, to push a first air/fuel mixture through the transfer passage into the second cylinder. The second fuel injector is configured to provide at least one fuel injection plume into the first air/fuel mixture.

A method in a network node comprises determining (610) whether at least a first D2D capable UE is or will be performing a D2D operation, and determining whether the at least the first D2D capable UE is or will be performing cellular operation. The method comprises adapting (620) activity and/or inactivity state configurations for the at least the first D2D UE based on the determining.

A content management system aggregates and provides users' interaction with a content item for display in an activity feed. Events corresponding to the users' interaction with the content item are provided in conjunction with a user interface of a native application displaying the content item. Though provided in conjunction with the native application, the events are maintained separate from the content data of the content item and displayed in the activity feed by an application separate from the native application of the content item. The activity feed permits users to exchange chat messages and retrieve information for multiple versions of the content item.

A method for improving the sensitivity of an assay to determine the pathogenicity of a plant root pathogen using a soil amendment is presented. The method involves growing the plant root in the presence of a soil amendment after exposure of the plant root to the pathogen. A method of breeding plants is also provided.

Apparatus and methods are provided for activity accessory including an energy harvester or generator. In an example, an activity accessory can include a first enclosure and an energy generator enclosed within the first enclosure. The energy generator can include a second enclosure. The energy generator can include a spherical magnet housed within the second enclosure and windings surrounding the second enclosure. Movement of the spherical magnet within the second enclosure can induce charge movement in the windings.

In this podcast, Thomas Domville discusses and explores how in iOS 13 users have the capability to create custom VoiceOver configurations for different tasks. For example, having a Different VoiceOver voice, speaking rate, and verbosity level for when using a specific app.

The Naukri JobSpeak is a monthly Index which calculates and records hiring activity based on the job listings on Naukri.com website month on month. The objective is to measure the hiring activities in various industries, cities, functional areas and experience levels.

For a (doctoral level) class I teach I do an activity where I hide a quarter on the quad (grassy open space the size of a soccer field, say) and a student has two minutes to find it. The student can recruit helpers, if they want, but has to split the fabulous 25 cent spoils evenly with each helper recruited.I'd like to do a similar activity in my now online class. For example, maybe it's a *very difficult* hidden picture or find one thing different in a field of similar images. I know a programmer could probably easily make a primitive game where you had to move your cursor over just the right pixel to find the quarter, but I'm not a programmer.

Can you think of an activity a person could do remotely (using zoom as a platform) where you would visually search for something but have relatively poor odds that you would actually find it in two minutes, and where having helpers to help you look would increase the odds of finding the thing in the time limit?

Can't wait to hear your ideas.

Most of us know what we need to do to be healthy, even if we don’t always do it. However, when a doctor prescribes a medication for what ails us we might take it more seriously. So what happens psychologically when a doctor prescribes a social activity to heal our ills? In this edition of...

Gov. Jay Inslee this week continued lifting restrictions included in his stay-home order meant to slow the spread of the new coronavirus, part of phase one in his four-phase plan to reopen the state. Some outdoor recreation opened earlier this week.

A report released by the Institute for Supply Management on Tuesday showed U.S. service sector activity contracted for the first time since December of 2009 in the month of April. The ISM said its non-manufacturing index tumbled to 41.8 in April from 52.5 in March, with a reading below 50 indicating a contraction in service sector activity.

The fourth entry in the supernatural series fails to offer anything new, but there are a handful of spooky and shocking moments.

The family of a man who went missing in Victoria's Latrobe Valley last month say they "fear the worst" and are urging anyone who has seen him to contact police.

UK manufacturers reported the quickest falls in output volumes and total new orders since 2009 in the three months to April, while business optimism plunged at a record pace. That’s according to the latest CBI quarterly Industrial Trends Survey.

See how the breaking of a drought can result in a boom for local tourism. In one small Victorian town, the long drought has broken and there's water back in the lake! Find out what attracts holiday-makers back in droves to the serenity of Bonnie Doon!

Feb 2020 article "...Wright, Bradfield, & Cairns (2013) noted a methodological separation of the intuitive logics approach popularized by Royal Dutch Shell (Wack, 1985a, 1985b) from firm‐level strategy concepts like business models (Zott, Amit, & Massa, 2011), competitive positioning (Porter, 1985), and resource capabilities (Barney, 1991)... The weakening of the connection, related to both the use of scenario planning and the research into it, is the historical connection to strategy process research."

TRB’s Airport Cooperative Research Program (ACRP) Report 76: Addressing Uncertainty about Future Airport Activity Levels in Airport Decision Making provides a systems analysis methodology that augments standard airport master planning and strategic planning approaches. The methodology includes a set of tools for improving the understanding and application of risk and uncertainty in air traffic forecasts as well as for increasing the overall effectiveness of airport planning and decision making.

IBM Australia and the Melbourne Institute of Applied Economic and Social Research, University of Melbourne, today announced the launch of the IBM-Melbourne Institute 'Innovation Index of Australian Industry’ second edition. The Study revealed that the annual increase in the rate of innovative activity in Australia in 2006 was only 0.7 percent, with only four industries experiencing an increase in the annual rate of innovation in that period: communication services; mining; finance; and the insurance industry.

I have a short Mercatus policy brief on that topic, co-authored with Trace Mitchell.  Excerpt: Risk from reopening cannot fall to zero, but investments in safety by employers can bring real gains in many cases. Ideally, a plan should both minimize risk and encourage employers’ safety investments. In essence, policymakers should (1) limit liability in […]

The post Limiting liability for a resumption of business activity appeared first on Marginal REVOLUTION.

The moon isn't "dead" after all: Newly discovered ridges on the moon's surface are leading scientists to think that the moon might have an active tectonic system.

Oswin enjoying her first supervised enrichment activity. It ended when the nearby construction made a loud upsetting bang. #cat https://ift.tt/2TSjmef

Model-car building is one of the old-school hobbies enjoying a resurgence during the pandemic lockdown. Haven't done that in a while? Here's where to find a kit and what to look for.

"Harry Potter" mastermind J.K. Rowling has launched a new website called "Harry Potter at Home" to help distract families from the coronavirus crisis.

The suggestions surface for multiple intents for logged-in users.

Please visit Search Engine Land for the full article.

Previous studies have shown that sphingosine kinase interacting protein (SKIP) inhibits sphingosine kinase (SK) function in fibroblasts. SK phosphorylates sphingosine producing the potent signaling molecule sphingosine-1-phosphate (S1P). SKIP gene (SPHKAP) expression is silenced by hypermethylation of its promoter in acute myeloid leukemia (AML). However, why SKIP activity is silenced in primary AML cells is unclear. Here, we investigated the consequences of SKIP down-regulation in AML primary cells and the effects of SKIP re-expression in leukemic cell lines. Using targeted ultra-HPLC-tandem MS (UPLC-MS/MS), we measured sphingolipids (including S1P and ceramides) in AML and control cells. Primary AML cells had significantly lower SK activity and intracellular S1P concentrations than control cells, and SKIP-transfected leukemia cell lines exhibited increased SK activity. These findings show that SKIP re-expression enhances SK activity in leukemia cells. Furthermore, other bioactive sphingolipids such as ceramide were also down-regulated in primary AML cells. Of note, SKIP re-expression in leukemia cells increased ceramide levels 2-fold, inactivated the key signaling protein extracellular signal-regulated kinase, and increased apoptosis following serum deprivation or chemotherapy. These results indicate that SKIP down-regulation in AML reduces SK activity and ceramide levels, an effect that ultimately inhibits apoptosis in leukemia cells. The findings of our study contrast with previous results indicating that SKIP inhibits SK function in fibroblasts and therefore challenge the notion that SKIP always inhibits SK activity.

Sulfur is essential for biological processes such as amino acid biogenesis, iron–sulfur cluster formation, and redox homeostasis. To acquire sulfur-containing compounds from the environment, bacteria have evolved high-affinity uptake systems, predominant among which is the ABC transporter family. Theses membrane-embedded enzymes use the energy of ATP hydrolysis for transmembrane transport of a wide range of biomolecules against concentration gradients. Three distinct bacterial ABC import systems of sulfur-containing compounds have been identified, but the molecular details of their transport mechanism remain poorly characterized. Here we provide results from a biochemical analysis of the purified Escherichia coli YecSC-FliY cysteine/cystine import system. We found that the substrate-binding protein FliY binds l-cystine, l-cysteine, and d-cysteine with micromolar affinities. However, binding of the l- and d-enantiomers induced different conformational changes of FliY, where the l- enantiomer–substrate-binding protein complex interacted more efficiently with the YecSC transporter. YecSC had low basal ATPase activity that was moderately stimulated by apo FliY, more strongly by d-cysteine–bound FliY, and maximally by l-cysteine– or l-cystine–bound FliY. However, at high FliY concentrations, YecSC reached maximal ATPase rates independent of the presence or nature of the substrate. These results suggest that FliY exists in a conformational equilibrium between an open, unliganded form that does not bind to the YecSC transporter and closed, unliganded and closed, liganded forms that bind this transporter with variable affinities but equally stimulate its ATPase activity. These findings differ from previous observations for similar ABC transporters, highlighting the extent of mechanistic diversity in this large protein family.

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.

Purinergic signaling by extracellular ATP regulates a variety of cellular events and is implicated in both normal physiology and pathophysiology. Several molecules have been associated with the release of ATP and other small molecules, but their precise contributions have been difficult to assess because of their complexity and heterogeneity. Here, we report on the results of a gain-of-function screen for modulators of hypotonicity-induced ATP release using HEK-293 cells and murine cerebellar granule neurons, along with bioluminescence, calcium FLIPR, and short hairpin RNA–based gene-silencing assays. This screen utilized the most extensive genome-wide ORF collection to date, covering 90% of human, nonredundant, protein-encoding genes. We identified two ABCG1 (ABC subfamily G member 1) variants, which regulate cellular cholesterol, as modulators of hypotonicity-induced ATP release. We found that cholesterol levels control volume-regulated anion channel–dependent ATP release. These findings reveal novel mechanisms for the regulation of ATP release and volume-regulated anion channel activity and provide critical links among cellular status, cholesterol, and purinergic signaling.

Purinergic signaling by extracellular ATP regulates a variety of cellular events and is implicated in both normal physiology and pathophysiology. Several molecules have been associated with the release of ATP and other small molecules, but their precise contributions have been difficult to assess because of their complexity and heterogeneity. Here, we report on the results of a gain-of-function screen for modulators of hypotonicity-induced ATP release using HEK-293 cells and murine cerebellar granule neurons, along with bioluminescence, calcium FLIPR, and short hairpin RNA–based gene-silencing assays. This screen utilized the most extensive genome-wide ORF collection to date, covering 90% of human, nonredundant, protein-encoding genes. We identified two ABCG1 (ABC subfamily G member 1) variants, which regulate cellular cholesterol, as modulators of hypotonicity-induced ATP release. We found that cholesterol levels control volume-regulated anion channel–dependent ATP release. These findings reveal novel mechanisms for the regulation of ATP release and volume-regulated anion channel activity and provide critical links among cellular status, cholesterol, and purinergic signaling.

S-Palmitoylation is a reversible post-translational lipid modification that dynamically regulates protein functions. Voltage-gated sodium channels are subjected to S-palmitoylation and exhibit altered functions in different S-palmitoylation states. Our aim was to investigate whether and how S-palmitoylation regulates Nav1.6 channel function and to identify S-palmitoylation sites that can potentially be pharmacologically targeted. Acyl-biotin exchange assay showed that Nav1.6 is modified by S-palmitoylation in the mouse brain and in a Nav1.6 stable HEK 293 cell line. Using whole-cell voltage clamp, we discovered that enhancing S-palmitoylation with palmitic acid increases Nav1.6 current, whereas blocking S-palmitoylation with 2-bromopalmitate reduces Nav1.6 current and shifts the steady-state inactivation in the hyperpolarizing direction. Three S-palmitoylation sites (Cys1169, Cys1170, and Cys1978) were identified. These sites differentially modulate distinct Nav1.6 properties. Interestingly, Cys1978 is exclusive to Nav1.6 among all Nav isoforms and is evolutionally conserved in Nav1.6 among most species. Cys1978 S-palmitoylation regulates current amplitude uniquely in Nav1.6. Furthermore, we showed that eliminating S-palmitoylation at specific sites alters Nav1.6-mediated excitability in dorsal root ganglion neurons. Therefore, our study reveals S-palmitoylation as a potential isoform-specific mechanism to modulate Nav activity and neuronal excitability in physiological and diseased conditions.

Carla E. Cox
Aug 1, 2017; 30:157-160
From Research to Practice

Previous studies have shown that sphingosine kinase interacting protein (SKIP) inhibits sphingosine kinase (SK) function in fibroblasts. SK phosphorylates sphingosine producing the potent signaling molecule sphingosine-1-phosphate (S1P). SKIP gene (SPHKAP) expression is silenced by hypermethylation of its promoter in acute myeloid leukemia (AML). However, why SKIP activity is silenced in primary AML cells is unclear. Here, we investigated the consequences of SKIP down-regulation in AML primary cells and the effects of SKIP re-expression in leukemic cell lines. Using targeted ultra-HPLC-tandem MS (UPLC-MS/MS), we measured sphingolipids (including S1P and ceramides) in AML and control cells. Primary AML cells had significantly lower SK activity and intracellular S1P concentrations than control cells, and SKIP-transfected leukemia cell lines exhibited increased SK activity. These findings show that SKIP re-expression enhances SK activity in leukemia cells. Furthermore, other bioactive sphingolipids such as ceramide were also down-regulated in primary AML cells. Of note, SKIP re-expression in leukemia cells increased ceramide levels 2-fold, inactivated the key signaling protein extracellular signal-regulated kinase, and increased apoptosis following serum deprivation or chemotherapy. These results indicate that SKIP down-regulation in AML reduces SK activity and ceramide levels, an effect that ultimately inhibits apoptosis in leukemia cells. The findings of our study contrast with previous results indicating that SKIP inhibits SK function in fibroblasts and therefore challenge the notion that SKIP always inhibits SK activity.

Sulfur is essential for biological processes such as amino acid biogenesis, iron–sulfur cluster formation, and redox homeostasis. To acquire sulfur-containing compounds from the environment, bacteria have evolved high-affinity uptake systems, predominant among which is the ABC transporter family. Theses membrane-embedded enzymes use the energy of ATP hydrolysis for transmembrane transport of a wide range of biomolecules against concentration gradients. Three distinct bacterial ABC import systems of sulfur-containing compounds have been identified, but the molecular details of their transport mechanism remain poorly characterized. Here we provide results from a biochemical analysis of the purified Escherichia coli YecSC-FliY cysteine/cystine import system. We found that the substrate-binding protein FliY binds l-cystine, l-cysteine, and d-cysteine with micromolar affinities. However, binding of the l- and d-enantiomers induced different conformational changes of FliY, where the l- enantiomer–substrate-binding protein complex interacted more efficiently with the YecSC transporter. YecSC had low basal ATPase activity that was moderately stimulated by apo FliY, more strongly by d-cysteine–bound FliY, and maximally by l-cysteine– or l-cystine–bound FliY. However, at high FliY concentrations, YecSC reached maximal ATPase rates independent of the presence or nature of the substrate. These results suggest that FliY exists in a conformational equilibrium between an open, unliganded form that does not bind to the YecSC transporter and closed, unliganded and closed, liganded forms that bind this transporter with variable affinities but equally stimulate its ATPase activity. These findings differ from previous observations for similar ABC transporters, highlighting the extent of mechanistic diversity in this large protein family.

Purinergic signaling by extracellular ATP regulates a variety of cellular events and is implicated in both normal physiology and pathophysiology. Several molecules have been associated with the release of ATP and other small molecules, but their precise contributions have been difficult to assess because of their complexity and heterogeneity. Here, we report on the results of a gain-of-function screen for modulators of hypotonicity-induced ATP release using HEK-293 cells and murine cerebellar granule neurons, along with bioluminescence, calcium FLIPR, and short hairpin RNA–based gene-silencing assays. This screen utilized the most extensive genome-wide ORF collection to date, covering 90% of human, nonredundant, protein-encoding genes. We identified two ABCG1 (ABC subfamily G member 1) variants, which regulate cellular cholesterol, as modulators of hypotonicity-induced ATP release. We found that cholesterol levels control volume-regulated anion channel–dependent ATP release. These findings reveal novel mechanisms for the regulation of ATP release and volume-regulated anion channel activity and provide critical links among cellular status, cholesterol, and purinergic signaling.

S-Palmitoylation is a reversible post-translational lipid modification that dynamically regulates protein functions. Voltage-gated sodium channels are subjected to S-palmitoylation and exhibit altered functions in different S-palmitoylation states. Our aim was to investigate whether and how S-palmitoylation regulates Nav1.6 channel function and to identify S-palmitoylation sites that can potentially be pharmacologically targeted. Acyl-biotin exchange assay showed that Nav1.6 is modified by S-palmitoylation in the mouse brain and in a Nav1.6 stable HEK 293 cell line. Using whole-cell voltage clamp, we discovered that enhancing S-palmitoylation with palmitic acid increases Nav1.6 current, whereas blocking S-palmitoylation with 2-bromopalmitate reduces Nav1.6 current and shifts the steady-state inactivation in the hyperpolarizing direction. Three S-palmitoylation sites (Cys1169, Cys1170, and Cys1978) were identified. These sites differentially modulate distinct Nav1.6 properties. Interestingly, Cys1978 is exclusive to Nav1.6 among all Nav isoforms and is evolutionally conserved in Nav1.6 among most species. Cys1978 S-palmitoylation regulates current amplitude uniquely in Nav1.6. Furthermore, we showed that eliminating S-palmitoylation at specific sites alters Nav1.6-mediated excitability in dorsal root ganglion neurons. Therefore, our study reveals S-palmitoylation as a potential isoform-specific mechanism to modulate Nav activity and neuronal excitability in physiological and diseased conditions.

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.

The cellular energy sensor AMP-activated protein kinase (AMPK) is a metabolic regulator that mediates adaptation to nutritional variations to maintain a proper energy balance in cells. We show here that suckling-weaning and fasting-refeeding transitions in rodents are associated with changes in AMPK activation and the cellular energy state in the liver. These nutritional transitions were characterized by a metabolic switch from lipid to glucose utilization, orchestrated by modifications in glucose levels and the glucagon/insulin ratio in the bloodstream. We therefore investigated the respective roles of glucose and pancreatic hormones on AMPK activation in mouse primary hepatocytes. We found that glucose starvation transiently activates AMPK, whereas changes in glucagon and insulin levels had no impact on AMPK. Challenge of hepatocytes with metformin-induced metabolic stress strengthened both AMPK activation and cellular energy depletion under limited-glucose conditions, whereas neither glucagon nor insulin altered AMPK activation. Although both insulin and glucagon induced AMPKα phosphorylation at its Ser485/491 residue, they did not affect its activity. Finally, the decrease in cellular ATP levels in response to an energy stress was additionally exacerbated under fasting conditions and by AMPK deficiency in hepatocytes, revealing metabolic inflexibility and emphasizing the importance of AMPK for maintaining hepatic energy charge. Our results suggest that nutritional changes (i.e. glucose availability), rather than the related hormonal changes (i.e. the glucagon/insulin ratio), sensitize AMPK activation to the energetic stress induced by the dietary transition during fasting. This effect is critical for preserving the cellular energy state in the liver.