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Supplementary Figure 2 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Materials and Methods, Figure Legends 1-7, Table 1 Legend from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Figure 5 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Figure 3 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Table 1 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Figure 1 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Figure 4 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Figure 6 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

Supplementary Figure 7 from Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation

The N-acetyltransferase arrest defective 1 (ARD1) is an important regulator of cell growth and differentiation that has emerged recently as a critical molecule in cancer progression. However, the regulation of the enzymatic and biological activities of human ARD1 (hARD1) in cancer is presently poorly understood. Here, we report that hARD1 undergoes autoacetylation and that this modification is essential for its functional activation. Using liquid chromatography-tandem mass spectrometry and site-directed mutational analyses, we identified K136 residue as an autoacetylation target site. K136R mutation abolished the ability of hARD1 to promote cancer cell growth in vitro and tumor xenograft growth in vivo. Mechanistic investigations revealed that hARD1 autoacetylation stimulated cyclin D1 expression through activation of the transcription factors β-catenin and activator protein-1. Our results show that hARD1 autoacetylation is critical for its activation and its ability to stimulate cancer cell proliferation and tumorigenesis. Cancer Res; 70(11); 4422–32. ©2010 AACR.

Nuptial gift-giving or courtship feeding is prevalent across. In an extreme case, females eat male body parts; in another case, females derive nutrients from males’ seminal fluids1. The nursery web spider, Pisaura mirabilis, females store more sperm from nuptial gift-giving males than those offering no gift with the identical copulation duration2. However, it is not known how females evaluate nuptial gifts and adjust sperm storage. Here, we show that Drosophila melanogaster females hold the ejaculate of starved males for shorter period and store less number of their sperm. A knock-down of the sugar transporter Tret1-1 in neurons that express the neuropeptide diuretic hormone 44 (Dh44-PI) critical for the ejaculate holding3 and detection of the nutritional value of sugar4 impairs the female’s ability to adjust the ejaculate holding period according to the male energy status. A galactoside selectively present in the male ejaculate activates Dh44-PI neurons in the brain to secrete Dh44, and starvation reduces its production by approximately 50%. RNAi-knockdown of glycosyltransferases, including UGT305A1, allows males to produce significantly lower amounts of the galactoside without starvation. Females mated with UGT305A1 knockdown males hold the ejaculate shorter, store less sperm and lay fewer eggs. The seminal galactoside enters the female hemocoel during mating, stimulates the activity of Dh44-PI neurons in the brain, augments the secretion of Dh44, and increase the ejaculate holding period, thereby enabling the uptake of injected nutrients and sperm. These evidence suggest that the galactoside signals reflecting the quality of male partners increase sperm storage and may be a source of nutrients used for egg production. Together, this study provides a molecular and cellular framework for understanding how females evaluate courtship feeding and optimize sexual selection after mating.

Plasma membrane repair defects cause human muscle and heart diseases. In the early stage of membrane repair, TRIM72/MG53 nucleates vesicles to the damaged site within seconds. Despite the therapeutic potential of TRIM72/MG53, the molecular mechanisms are poorly understood. Here, we present the structure of TRIM72, the first complete model of a TRIM E3 ligase. Structure-guided functional analysis revealed a unique phospholipid recognition mode in which a pair of PRYSPRY domains interacts with negatively charged membranes. In subsequent biochemical analyses, the interaction between TRIM72 and the phosphatidylserine-enriched membrane was shown to be critical for both the oligomeric assembly and ubiquitination activity of TRIM72. We elucidated a higher-order model of TRIM72 assembly on the phospholipid bilayer using cryogenic electron tomography followed by subtomogram averaging. We developed a working molecular model of TRIM72 through integrated structural and biochemical techniques. The findings provide a fundamental basis for the study of TRIM E3 ligases, which share a conserved molecular architecture, and provide further insights into the general regulation of RING-type E3 ligases through the cooperation of multiple domains like those in higher-order assemblies.

Cardiac hypertrophic signaling cascades resulting in heart failure diseases are mediated by protein phosphorylation. Recent developments in mass spectrometry-based phosphoproteomics have led to the identification of thousands of differentially phosphorylated proteins and their phosphorylation sites. However, functional studies of these differentially phosphorylated proteins have not been conducted in a large-scale or high-throughput manner due to a lack of methods capable of revealing the functional relevance of each phosphorylation site. In this study, an integrated approach combining quantitative phosphoproteomics and cell-based functional screening using phosphorylation competition peptides was developed. A pathological cardiac hypertrophy model, junctate-1 transgenic mice and control mice, were analyzed using label-free quantitative phosphoproteomics to identify differentially phosphorylated proteins and sites. A cell-based functional assay system measuring hypertrophic cell growth of neonatal rat ventricle cardiomyocytes (NRVMs) following phenylephrine treatment was applied, and changes in phosphorylation of individual differentially phosphorylated sites were induced by incorporation of phosphorylation competition peptides conjugated with cell-penetrating peptides. Cell-based functional screening against 18 selected phosphorylation sites identified three phosphorylation sites (Ser-98, Ser-179 of Ldb3, and Ser-1146 of palladin) displaying near-complete inhibition of cardiac hypertrophic growth of NRVMs. Changes in phosphorylation levels of Ser-98 and Ser-179 in Ldb3 were further confirmed in NRVMs and other pathological/physiological hypertrophy models, including transverse aortic constriction and swimming models, using site-specific phospho-antibodies. Our integrated approach can be used to identify functionally important phosphorylation sites among differentially phosphorylated sites, and unlike conventional approaches, it is easily applicable for large-scale and/or high-throughput analyses.

The mechanisms underlying the vulnerability and resilience of an individual to stress are only partly understood. Response to stress is determined by behavioral and biochemical changes in the brain. Chronic ultra-mild stress (CUMS) induces an anhedonic-like state in mice that resembles symptoms of human depression. This study reports the role of cereblon (CRBN) in regulating the metabolic and antioxidant status of neuronal tissues in the mouse model of CUMS. Intriguingly, Crbn

Alternative pre-mRNA splicing is a critical step to generate multiple transcripts, thereby dramatically enlarging the proteomic diversity. Thus, a common feature of most alternative splicing factor knockout models is lethality. However, little is known about lineage-specific alternative splicing regulators in a physiological setting. Here, we report that NSrp70 is selectively expressed in developing thymocytes, highest at the double-positive (DP) stage. Global splicing and transcriptional profiling revealed that NSrp70 regulates the cell cycle and survival of thymocytes by controlling the alternative processing of various RNA splicing factors, including the oncogenic splicing factor SRSF1. A conditional-knockout of Nsrp1 (NSrp70-cKO) using CD4Cre developed severe defects in T cell maturation to single-positive thymocytes, due to insufficient T cell receptor (TCR) signaling and uncontrolled cell growth and death. Mice displayed severe peripheral lymphopenia and could not optimally control tumor growth. This study establishes a model to address the function of lymphoid-lineage-specific alternative splicing factor NSrp70 in a thymic T cell developmental pathway.

Potential biomarkers for Alzheimer’s disease (AD) include amyloid β1–42 (Aβ1–42), t-Tau, p-Tau181, neurofilament light chain (NFL), and neuroimaging biomarkers. Their combined use is useful for diagnosing and monitoring the progress of AD. Therefore, further development of a combination of these biomarkers is essential. We investigated whether plasma NFL/Aβ1–42 can serve as a plasma-based primary screening biomarker reflecting brain neurodegeneration and amyloid pathology in AD for monitoring disease progression and early diagnosis. We measured the NFL and Aβ1–42 concentrations in the CSF and plasma samples and performed correlation analysis to evaluate the utility of these biomarkers in the early diagnosis and monitoring of AD spectrum disease progression. Pearson’s correlation analysis was used to analyse the associations between the fluid biomarkers and neuroimaging data. The study included 136 participants, classified into five groups: 28 cognitively normal individuals, 23 patients with preclinical AD, 22 amyloid-negative patients with amnestic mild cognitive impairment, 32 patients with prodromal AD, and 31 patients with AD dementia. With disease progression, the NFL concentrations increased and Aβ1–42 concentrations decreased. The plasma and CSF NFL/Aβ1–42 were strongly correlated (r = 0.558). Plasma NFL/Aβ1–42 was strongly correlated with hippocampal volume/intracranial volume (r = 0.409). In early AD, plasma NFL/Aβ1–42 was associated with higher diagnostic accuracy than the individual biomarkers. Moreover, in preclinical AD, plasma NFL/Aβ1–42 changed more rapidly than the CSF t-Tau or p-Tau181 concentrations. Our findings highlight the utility of plasma NFL/Aβ1–42 as a non-invasive plasma-based biomarker for early diagnosis and monitoring of AD spectrum disease progression.

Potential biomarkers for Alzheimer’s disease (AD) include amyloid β1–42 (Aβ1–42), t-Tau, p-Tau181, neurofilament light chain (NFL), and neuroimaging biomarkers. Their combined use is useful for diagnosing and monitoring the progress of AD. Therefore, further development of a combination of these biomarkers is essential. We investigated whether plasma NFL/Aβ1–42 can serve as a plasma-based primary screening biomarker reflecting brain neurodegeneration and amyloid pathology in AD for monitoring disease progression and early diagnosis. We measured the NFL and Aβ1–42 concentrations in the CSF and plasma samples and performed correlation analysis to evaluate the utility of these biomarkers in the early diagnosis and monitoring of AD spectrum disease progression. Pearson’s correlation analysis was used to analyse the associations between the fluid biomarkers and neuroimaging data. The study included 136 participants, classified into five groups: 28 cognitively normal individuals, 23 patients with preclinical AD, 22 amyloid-negative patients with amnestic mild cognitive impairment, 32 patients with prodromal AD, and 31 patients with AD dementia. With disease progression, the NFL concentrations increased and Aβ1–42 concentrations decreased. The plasma and CSF NFL/Aβ1–42 were strongly correlated (r = 0.558). Plasma NFL/Aβ1–42 was strongly correlated with hippocampal volume/intracranial volume (r = 0.409). In early AD, plasma NFL/Aβ1–42 was associated with higher diagnostic accuracy than the individual biomarkers. Moreover, in preclinical AD, plasma NFL/Aβ1–42 changed more rapidly than the CSF t-Tau or p-Tau181 concentrations. Our findings highlight the utility of plasma NFL/Aβ1–42 as a non-invasive plasma-based biomarker for early diagnosis and monitoring of AD spectrum disease progression.

Background Lipid rafts (LRs), cholesterol‐enriched microdomains on cell membranes, are increasingly viewed as signalling platforms governing critical facets of cancer progression. The phenotype of cancer stem‐like cells (CSCs) presents significant hurdles for successful cancer treatment, and the expression of several CSC markers is associated with LR integrity. However, LR implications in CSCs remain unclear. Methods This study evaluated the biological and molecular functions of LRs in colorectal cancer (CRC) by using an LR‐disrupting alkylphospholipid (APL) drug, miltefosine. The mechanistic role of miltefosine in CSC inhibition was examined through normal or tumour intestinal mouse organoid, human CRC cell, CRC xenograft and miltefosine treatment gene expression profile analyses. Results Miltefosine suppresses CSC populations and their self‐renewal activities in CRC cells, a CSC‐targeting effect leading to irreversible disruption of tumour‐initiating potential in vivo. Mechanistically, miltefosine reduced the expression of a set of genes, leading to stem cell death. Among them, miltefosine transcriptionally inhibited checkpoint kinase 1 (CHEK1), indicating that LR integrity is essential for CHEK1 expression regulation. In isolated CD44high CSCs, we found that CSCs exhibited stronger therapy resistance than non‐CSC counterparts by preventing cell death through CHEK1‐mediated cell cycle checkpoints. However, inhibition of the LR/CHEK1 axis by miltefosine released cell cycle checkpoints, forcing CSCs to enter inappropriate mitosis with accumulated DNA damage and resulting in catastrophic cell death. Conclusion Our findings underscore the therapeutic potential of LR‐targeting APLs for CRC treatment that overcomes the therapy‐resistant phenotype of CSCs, highlighting the importance of the LR/CHEK1 axis as a novel mechanism of APLs., Miltefosine exhibits preferential cytotoxicity against colorectal cancer stem‐like cells (CSCs). Mechanistically, inhibition of lipid raft/checkpoint kinase 1 (LR/CHEK1) axis by miltefosine releases cell cycle checkpoints and drives the inappropriate mitotic entry in the presence of unresolved DNA damage accumulation, thereby inducing catastrophic mitotic cell death in CSCs. Our findings underscore the therapeutic potential of lipid raft–targeting alkylphospholipids for colorectal cancer treatment that overcomes the therapy‐resistant phenotype of CSCs.

Aim To develop more effective and long-lasting antiobesity and antidiabetic therapeutics by employing novel chemical modifications of glucagon-like peptide-1 receptor (GLP-1R) agonists. Methods We constructed novel unimolecular dual agonists of GLP-1R and glucagon receptor prepared by linking sEx-4 and native glucagon (GCG) via lysine or triazole [sEx4-GCG(K) and sEx4-GCG(T), respectively] and evaluated their antiobesity and antidiabetic efficacy in the diabetic and obese mouse model. Results Both sEx4-GCG(K) and sEx4-GCG(T) showed the beneficial metabolic effects of GLP-1 and glucagon: they promoted weight loss and ameliorated insulin resistance and hepatic steatosis. They also increased thermogenesis in brown adipose tissue, and lipolysis and β-oxidation in white adipose tissue, with concomitant suppression of lipogenesis. Furthermore, both dual agonists activated the 5'-AMP-activated protein kinase signalling pathway and prevented palmitate-induced oxidative stress in skeletal muscle cells. Conclusion Through their complementary dual agonism, sEx4-GCG(T) and sEx4-GCG(K) induce more marked weight loss and metabolic improvements than conventional agonists, and could be developed as novel therapeutic agents for the treatment of obesity and associated metabolic disorders in humans.

Background: Potential biomarkers for Alzheimer’s disease (AD) include amyloid β1-42 (Aβ1-42), t-Tau, p-Tau 181 , neurofilament light chain (NFL), and neuroimaging, but the feasibility of using these for the diagnosis and monitoring of AD has not been reported. Therefore, further development of these biomarkers is essential.Methods: We measured NFL and Aβ1-42 concentrations in CSF and plasma samples from 136 participants and performed correlation analysis to evaluate the utility of these biomarkers for early diagnosis and monitoring of disease progression in AD spectrum.Results: With disease progression, concentrations of NFL increased, and those of Aβ1-42 were decreases. The plasma and CSF values of NFL/Aβ1-42 were strongly correlated (r = 0.558). In addition, the plasma value of NFL/Aβ1-42 was strong correlated with hippocampal volume/ICV ( r = 0.409). In the early stage of AD, the plasma_NFL/Aβ1-42 was associated with higher diagnostic accuracy than were the individual biomarkers. Moreover, in preclinical AD, plasma_NFL/Aβ1-42 changed more rapidly than did either the t-Tau or the p-Tau181 values measured in the CSF.Conclusions: Taken together, our findings highlight the utility of plasma_NFL/Aβ1-42 as a biomarker for early diagnosis and monitoring of disease progression in AD spectrum.

Microbial conversion of carbon monoxide (CO) to acetate is a promising upcycling strategy for carbon sequestration. Herein, we demonstrate that CO conversion and acetate production rates of Eubacterium limosum KIST612 strain can be improved by in silico prediction and in vivo assessment. The mimicked CO metabolic model of KIST612 predicted that overexpressing the CO dehydrogenase (CODH) increases CO conversion and acetate production rates. To validate the prediction, we constructed mutant strains overexpressing CODH gene cluster and measured their CO conversion and acetate production rates. A mutant strain (ELM031) co-overexpressing CODH, coenzyme CooC2 and ACS showed a 3.1 × increased specific CO oxidation rate as well as 1.4 × increased specific acetate production rate, compared to the wild type strain. The transcriptional and translational data with redox balance analysis showed that ELM031 has enhanced reducing potential from up-regulation of ferredoxin and related metabolism directly linked to energy conservation.

Cancer-associated fibroblasts (CAFs) in the tumor microenvironment play major roles in supporting cancer progression. A previous report showed that SPIN90 downregulation is correlated with CAF activation and that SPIN90-deficient CAFs promote breast cancer progression. However, the mechanisms that mediate cancer-stroma interaction and how such interactions regulate cancer progression are not well understood. Here, we show that extra domain A (EDA)-containing fibronectin (FN), FN(+)EDA, produced by mouse embryonic fibroblasts (MEFs) derived from Spin90-knockout (KO) mice increases their own myofibroblast differentiation, which facilitates breast cancer progression. Increased FN(+)EDA in Spin90-KO MEFs promoted fibril formation in the extracellular matrix (ECM) and specifically interacted with integrin α4β1 as the mediating receptor. Moreover, FN(+)EDA expression by Spin90-KO MEFs increased proliferation, migration, and invasion of breast cancer cells. Irigenin, a specific inhibitor of the interaction between integrin α4β1 and FN(+)EDA, significantly blocked the effects of FN(+)EDA, such as fibril formation by Spin90-KO MEFs and proliferation, migration, and invasion of breast cancer cells. In orthotopic breast cancer mouse models, irigenin injection remarkably reduced tumor growth and lung metastases. It was supported by that FN(+)EDA in assembled fibrils was accumulated in cancer stroma of human breast cancer patients in which SPIN90 expression was downregulated. Our data suggest that SPIN90 downregulation increases FN(+)EDA and promotes ECM stiffening in breast cancer stroma through an assembly of long FN(+)EDA-rich fibrils; moreover, engagement of the Integrin α4β1 receptor facilitates breast cancer progression. Inhibitory effects of irigenin on tumor growth and metastasis suggest the potential of this agent as an anticancer therapeutic.

The N-degron pathway determines the half-life of proteins in both prokaryotes and eukaryotes by precisely recognizing the N-terminal residue (N-degron) of substrates. ClpS proteins from bacteria bind to substrates containing hydrophobic N-degrons (Leu, Phe, Tyr, and Trp) and deliver them to the caseinolytic protease system ClpAP. This mechanism is preserved in organelles such as mitochondria and chloroplasts. Bacterial ClpS adaptors bind preferentially to Leu and Phe N-degrons; however, ClpS1 from Arabidopsis thaliana (AtClpS1) shows a difference in that it binds strongly to Phe and Trp N-degrons and only weakly to Leu. This difference in behavior cannot be explained without structural information due to the high sequence homology between bacterial and plant ClpS proteins. Here, we report the structure of AtClpS1 at 2.0 A resolution in the presence of a bound N-degron. The key determinants for α-amino group recognition are conserved among all ClpS proteins, but the α3-helix of eukaryotic AtClpS1 is significantly shortened, and consequently, a loop forming a pocket for the N-degron is moved slightly outward to enlarge the pocket. In addition, amino acid replacement from Val to Ala causes a reduction in hydrophobic interactions with Leu N-degron. A combination of the fine-tuned hydrophobic residues in the pocket and the basic gatekeeper at the entrance of the pocket controls the N-degron selectivity of the plant ClpS protein.

Protein aggregation can induce explicit neurotoxic events that trigger a number of presently untreatable neurodegenerative disorders. Chaperones, on the other hand, play a neuroprotective role due to their ability to unfold and refold abnormal proteins. Progressive nature of neurotoxic events makes it important to discover endogenous factors that affect pathological and molecular phenotypes of neurodegeneration in animal models. Here, we identified microtubule-associated protein tau, and chaperones Hsp70 (heat shock protein 70) and DNAJA1 (DJ2) as endogenous substrates of cereblon (CRBN), a substrate-recruiting-subunit of cullin4-RING-E3-ligase. This recruitment results in ubiquitin-mediated degradation of tau, Hsp70, and DJ2. Knocking-out CRBN enhances chaperone activity of DJ2, resulting in decreased phosphorylation and aggregation of tau, improved association of tau with microtubules and reduced accumulation of pathological tau across brain. Functionally abundant DJ2 could prevent tau aggregation induced by various factors like okadaic acid and heparin. Depletion of CRBN also decreases the activity of tau-kinases including GSK3α/β, ERK, and p38. Intriguingly, we found a high expression of CRBN and low levels of DJ2 in neuronal tissues of 5XFAD and APP knock-in male mice models of Alzheimer’s disease (AD). This implies that CRBN-mediated DJ2/Hsp70-pathway may be compromised in neurodegeneration. Being one of the primary pathogenic events, elevated CRBN can be a contributing factor for tauopathies. Our data provide a functional link between CRBN and DJ2/Hsp70 chaperone machinery in abolishing the cytotoxicity of aggregation-prone tau and suggest that Crbn-/- mice serve as an animal model of resistance against tauopathies to further exploration of the molecular mechanisms of neurodegeneration. SIGNIFICANCE STATEMENT This work highlights a potential molecular mechanism by which CRBN influcences the aggregation and toxicity of tau via molecular chaperone modulation. Combining in vivo techniques and molecular analyses, we show that CRBN tunes fate of tau by regulating chaperone activity of Hsp70/DJ2, and kinase activity of tau-kinases. Knocking-out CRBN relieves DJ2 to detoxify cell-damaging conformers of tau in vitro and in vivo. Consequently, tau enters into a dynamic folding pathway and associates with microtubules rendering them intact and functional. These findings provide the rationale for proposing CRBN to influence tauopathies via tuning chaperone activities and emphasize that DJ2 can be a promising target for the treatment of tauopathies to reduce the toxicity of abnormal aggregates.

Conventional ubiquitylation occurs through an ATP-dependent three-enzyme cascade (E1, E2, and E3) that mediates the covalent conjugation of the C-terminus of ubiquitin to a lysine on the substrate. SdeA, which belongs to the SidE effector family of Legionella pneumophila, can transfer ubiquitin to endoplasmic reticulum-associated Rab-family GTPases in a manner independent of E1 and E2 enzymes. The novel ubiquitin-modifying enzyme SdeA utilizes NAD+ as a cofactor to attach ubiquitin to a serine residue of the substrate. Here, to elucidate the coupled enzymatic reaction of NAD+ hydrolysis and ADP-ribosylation of ubiquitin in SdeA, we characterized the mono-ADP-ribosyltransferase domain of SdeA and show that it consists of two sub-domains termed mART-N and mART-C. The crystal structure of the mART-C domain of SdeA was also determined in free form and in complex with NAD+ at high resolution. Furthermore, the spatial orientations of the N-terminal deubiquitylase, phosphodiesterase, mono-ADP-ribosyltransferase, and C-terminal coiled-coil domains within the 180-kDa full-length SdeA were determined. These results provide insight into the unusual ubiquitylation mechanism of SdeA and expand our knowledge on the structure-function of mono-ADP-ribosyltransferases.

Exendin-4, a 39 amino acid peptide isolated from the saliva of the Gila monster, plays an important role in regulating glucose homeostasis, and is used clinically for the treatment of type 2 diabetes. Exendin-4 shares 53% sequence identity with the incretin hormone glucagon-like peptide 1 (GLP-1) but, unlike GLP-1, is highly resistant to proteolytic enzymes such as dipeptidyl peptidase IV (DPP-IV) and neutral endopeptidase 24.11 (NEP 24.11). Herein, we focused on the structure and function of the C-terminal Trp-cage of exendin-4, and suggest that it may be structurally required for resistance to proteolysis by NEP 24.11. Using a series of substitutions and truncations of the C-terminal Trp-cage, we found that residues 1-33, including the N-terminal and helical regions of wild-type (WT) exendin-4, is the minimum motif required for both high peptidase resistance and potent activity toward the GLP-1 receptor comparable to WT exendin-4. To improve the therapeutic utility of C-terminally truncated exendin-4, we incorporated various fatty acids into exendin-4(1-33) in which Ser33 was substituted with Lys for acylation. Exendin-4(1-32)K-capric acid exhibited the most well balanced activity, with much improved therapeutic utility for regulating blood glucose and body weight relative to WT exendin-4.

SAM domain and HD domain containing protein 1 (SAMHD1) is a deoxynucleotide triphosphohydrolase (dNTPase) that inhibits retroviruses by depleting intracellular deoxynucleotide triphosphates (dNTPs) in non-cycling myeloid cells. Although SAMHD1 is expressed ubiquitously throughout the human body, the molecular mechanisms regulating its enzymatic activity and function in non-immune cells are relatively unexplored. Here, we demonstrate that the dNTPase activity of SAMHD1 is regulated by acetylation, which promotes cell cycle progression in cancer cells. SAMHD1 is acetylated at residue lysine 405 (K405) in vitro and in vivo by an acetylatransferase, arrest defective protein 1 (ARD1). Acetylated SAMHD1 wildtype proteins have enhanced dNTPase activity in vitro, whereas non-acetylated arginine substituted mutants (K405R) do not. K405R mutant expressing cancer cells have reduced G1/S transition and slower proliferation compared to wildtype. SAMHD1 acetylation levels are strongest during the G1 phase, indicating a role during G1 phase. Collectively, these findings suggest that SAMHD1 acetylation enhances its dNTPase activity and promotes cancer cell proliferation. Therefore, SAMHD1 acetylation may be a potent therapeutic target for cancer treatment.

PDK1 is essential for T cell receptor (TCR)-mediated activation of NF-κB, and PDK1-induced phosphorylation of PKCθ is important for TCR-induced NF-κB activation. However, inverse regulation of PDK1 by PKCθ during T cell activation has not been investigated. In this study, we found that PKCθ is involved in human PDK1 phosphorylation and that its kinase activity is crucial for human PDK1 phosphorylation. Mass spectrometry analysis of wild-type PKCθ or of kinase-inactive form of PKCθ revealed that PKCθ induced phosphorylation of human PDK1 at Ser-64. This PKCθ-induced PDK1 phosphorylation positively regulated T cell activation and TCR-induced NF-κB activation. Moreover, phosphorylation of human PDK1 at Ser-64 increased the stability of human PDK1 protein. These results suggest that Ser-64 is an important phosphorylation site that is part of a positive feedback loop for human PDK1-PKCθ-mediated T cell activation.

Background Cinnamomum cassia bark is the outer skin of an evergreen tall tree belonging to the family Lauraceae containing several active components such as essential oils (cinnamic aldehyde and cinnamyl aldehyde), tannin, mucus and carbohydrate. They have various biological functions including anti-oxidant, anti-microbial, anti-inflammation, anti-diabetic and anti-tumor activity. Previously, we have reported that anti-cancer effect of cinnamon extracts is associated with modulation of angiogenesis and effector function of CD8+ T cells. In this study, we further identified that anti-tumor effect of cinnamon extracts is also link with enhanced pro-apoptotic activity by inhibiting the activities NFκB and AP1 in mouse melanoma model. Methods Water soluble cinnamon extract was obtained and quality of cinnamon extract was evaluated by HPLC (High Performance Liquid Chromatography) analysis. In this study, we tested anti-tumor activity and elucidated action mechanism of cinnamon extract using various types of tumor cell lines including lymphoma, melanoma, cervix cancer and colorectal cancer in vitro and in vivo mouse melanoma model. Results Cinnamon extract strongly inhibited tumor cell proliferation in vitro and induced active cell death of tumor cells by up-regulating pro-apoptotic molecules while inhibiting NFκB and AP1 activity and their target genes such as Bcl-2, BcL-xL and survivin. Oral administration of cinnamon extract in melanoma transplantation model significantly inhibited tumor growth with the same mechanism of action observed in vitro. Conclusion Our study suggests that anti-tumor effect of cinnamon extracts is directly linked with enhanced pro-apoptotic activity and inhibition of NFκB and AP1 activities and their target genes in vitro and in vivo mouse melanoma model. Hence, further elucidation of active components of cinnamon extract could lead to development of potent anti-tumor agent or complementary and alternative medicine for the treatment of diverse cancers.

The hydroxymethylation of cytosine bases plays a vital role in the phage DNA protection system inside the host Escherichia coli. This modification is known to be catalyzed by the dCMP hydroxymethylase from bacteriophage T4 (T4dCH); structural information on the complexes with the substrate, dCMP and the co-factor, tetrahydrofolate is currently available. However, the detailed mechanism has not been understood clearly owing to a lack of structure in the complex with a reaction intermediate. We have applied the X-ray free electron laser (XFEL) technique to determine a high-resolution structure of a T4dCH D179N active site mutant. The XFEL structure was determined at room temperature and exhibited several unique features in comparison with previously determined structures. Unexpectedly, we observed a bulky electron density at the active site of the mutant that originated from the physiological host (i.e., E. coli). Mass-spectrometric analysis and a cautious interpretation of an electron density map indicated that it was a dTMP molecule. The bound dTMP mimicked the methylene intermediate from dCMP to 5′-hydroxymethy-dCMP, and a critical water molecule for the final hydroxylation was convincingly identified. Therefore, this study provides information that contributes to the understanding of hydroxymethylation.

Rationale: SERCA2a, sarco-endoplasmic reticulum Ca 2+ -ATPase, is a critical determinant of cardiac function. Reduced level and activity of SERCA2a are major features of heart failure. Accordingly, intensive efforts have been made to develop efficient modalities for SERCA2a activation. We showed that the activity of SERCA2a is enhanced by post-translational modification with SUMO1 (small ubiquitin-like modifier 1). However, the roles of other post-translational modifications on SERCA2a are still unknown. Objective: In this study, we aim to assess the role of lysine acetylation on SERCA2a function and determine whether inhibition of lysine acetylation can improve cardiac function in the setting of heart failure. Methods and Results: The acetylation of SERCA2a was significantly increased in failing hearts of humans, mice, and pigs, which is associated with the reduced level of SIRT1 (sirtuin 1), a class III histone deacetylase. Downregulation of SIRT1 increased the SERCA2a acetylation, which in turn led to SERCA2a dysfunction and cardiac defects at baseline. In contrast, pharmacological activation of SIRT1 reduced the SERCA2a acetylation, which was accompanied by recovery of SERCA2a function and cardiac defects in failing hearts. Lysine 492 (K492) was of critical importance for the regulation of SERCA2a activity via acetylation. Acetylation at K492 significantly reduced the SERCA2a activity, presumably through interfering with the binding of ATP to SERCA2a. In failing hearts, acetylation at K492 appeared to be mediated by p300 (histone acetyltransferase p300), a histone acetyltransferase. Conclusions: These results indicate that acetylation/deacetylation at K492, which is regulated by SIRT1 and p300, is critical for the regulation of SERCA2a activity in hearts. Pharmacological activation of SIRT1 can restore SERCA2a activity through deacetylation at K492. These findings might provide a novel strategy for the treatment of heart failure.

Cationic antimicrobial peptides (CAMPs) are important antibiotics because they possess a broad spectrum of activity against both Gram-positive and Gram-negative bacteria, including those resistant to traditional antibiotics. The cyclic peptide bactenecin is a 12-amino acid CAMP that contains one intramolecular disulfide bond. To improve the antibacterial activity of bactenecin, we designed and synthesized several bactenecin analogs by applying multiple approaches, including amino acid substitution, use of the d -enantiomeric form, and lipidation. Among the synthetic analogs, d -enantiomeric bactenecin conjugated to capric acid, which we named dBacK-(cap), exhibited a significantly enhanced antibacterial spectrum with MIC values ranging from 1 to 8 μM against both Gram-positive and Gram-negative bacteria, including some drug-resistant bacteria. Upon exposure to dBacK-(cap), S. aureus cells were killed within 1 h at the MIC value, but full inactivation of E. coli required over 2 h. These results indicate that covalent addition of a d -amino acid and a fatty acid to bactenecin is the most effective approach for enhancing its antibacterial activity.

Atopic dermatitis (AD) is a complex inflammatory skin disease mediated by immune cells of both adaptive and innate types. Among them, CD4(+) Th cells are one of major players of AD pathogenesis. Although the pathogenic role of Th2 cells has been well characterized, Th17/Th22 cells are also implicated in the pathogenesis of AD. However, the molecular mechanisms underlying pathogenic immune responses in AD remain unclear. We sought to investigate how the defect in the AD susceptibility gene, Ets1, is involved in AD pathogenesis in human and mice and its clinical relevance in disease severity by identifying Ets1 target genes and binding partners. Consistent with the decrease in ETS1 levels in severe AD patients and the experimental AD-like skin inflammation model, T cell–specific Ets1-deficient mice (Ets1(ΔdLck)) developed severe AD-like symptoms with increased pathogenic Th cell responses. A T cell–intrinsic increase of gp130 expression upon Ets1 deficiency promotes the gp130-mediated IL-6 signaling pathway, thereby leading to the development of severe AD-like symptoms. Functional blocking of gp130 by selective inhibitor SC144 ameliorated the disease pathogenesis by reducing pathogenic Th cell responses. Our results reveal a protective role of Ets1 in restricting pathogenic Th cell responses and suggest a potential therapeutic target for AD treatment.

Armadillo (ARM) repeat proteins constitute a large protein family with diverse and fundamental functions in all organisms, and armadillo repeat domains share high structural similarity. However, exactly how these structurally similar proteins can mediate diverse functions remains a long-standing question. Vac8 (vacuole related 8) is a multifunctional protein that plays pivotal roles in various autophagic pathways, including piecemeal microautophagy of the nucleus (PMN) and cytoplasm-to-vacuole targeting (Cvt) pathways in the budding yeast Saccharomyces cerevisiae. Vac8 comprises an H1 helix at the N terminus, followed by 12 armadillo repeats. Herein, we report the crystal structure of Vac8 bound to Atg13, a key component of autophagic machinery. The 70-Å extended loop of Atg13 binds to the ARM domain of Vac8 in an antiparallel manner. Structural, biochemical, and in vivo experiments demonstrated that the H1 helix of Vac8 intramolecularly associates with the first ARM and regulates its self-association, which is crucial for Cvt and PMN pathways. The structure of H1 helix-deleted Vac8 complexed with Atg13 reveals that Vac8[Δ19–33]-Atg13 forms a heterotetramer and adopts an extended superhelical structure exclusively employed in the Cvt pathway. Most importantly, comparison of Vac8-Nvj1 and Vac8-Atg13 provides a molecular understanding of how a single ARM domain protein adopts different quaternary structures depending on its associated proteins to differentially regulate 2 closely related but distinct cellular pathways. Abbreviations Ape1: aminopeptidase I; ARM: armadillo repeat; Atg: autophagy-related; AUC: analytical ultracentrifugation; Cvt: cytoplasm-to-vacuole targeting; DIC: differential interference contrast; GFP: green fluorescent protein; GST: glutathione-S-transferase; ITC: isothermal titration calorimetry; NVJ: nucleus-vacuole junction; PDB: protein data bank; PMN: piecemeal microautophagy of the nucleus; prApe1: precursor Ape1; RMSD: root-mean-square deviation; SAXS: small-angle X-ray scattering; SD-N: nitrogen starvation medium; SEC: size-exclusion chromatography; tAtg13: Atg13 construct comprising residues 567–695; tNvj1: Nvj1 construct comprising residues 229–321; tVac8: Vac8 construct comprising residues 10–515; Vac8: vacuole related 8

This study analyzed the effect of methanol on the metabolism of syngas components (i.e., H2 and CO) by the syngas fermenting acetogenic strain E. limosum KIST612. The culture characteristics and relevant proteomic expressions (as fold changes) were carefully analyzed under CO/CO2 and H2/CO2 conditions with and without methanol addition, as well as, under methanol/CO2 conditions. The culture characteristics (specific growth rate and H2 consumption rate) under H2/CO2 conditions were greatly enhanced in the presence of methanol, by 4.0 and 2.7 times, respectively. However, the promoting effect of methanol was not significant under CO/CO2 conditions. Proteomic fold changes in most enzyme expression levels in the Wood-Ljungdahl pathway and chemiosmotic energy conservation also exhibited high correspondence between methanol and H2/CO2 but not between methanol and CO/CO2. These findings suggest the advantages of methanol addition to H2/CO2 for biomass enhancement and faster consumption of gaseous substrates during syngas fermentation.

Here, the effects of heat-killed Enterococcus faecalis EF-2001 (EF-2001) on atopic eczema (AE) were assessed. An AE model was established in vivo by repetitious topical exposure to 1-chloro-2,4-dinitrobenzene (CDNB) and dermatophagoidesfarinae extract (DFE) via application on each ear. Mice were administered EF-2001 orally for 4 weeks, dermal and epidermal ear thickness, mast cell infiltration of the ear tissue, and serum IgE and IgG2a levels were evaluated. Moreover, pathogenic cytokines levels of the ears, splenocytes, and cervical lymph nodes were determined. EF-2001 reduced AE symptoms grounded in the ear thickness, histopathological analysis, and serum IgE levels. Furthermore, EF-2001 attenuated mast cell infiltration in the ears and CDNB/DFE-induced various pathogenic cytokines levels of the ears, splenocytes and cervical lymph nodes. Thus, our data suggested that EF-2001 may have potential medicinal applications in the treatment of AE through its immunomodulatory properties.

// Young Soo Park 1, 5 , Dong Joon Kim 2 , Han Koo 2, 5 , Se Hwan Jang 3 , Yeon-Mi You 1, 5 , Jung Hee Cho 2 , Suk-Jin Yang 1 , Eun Sil Yu 4 , Yuri Jung 2 , Dong Chul Lee 1 , Jung-Ae Kim 2, 5 , Zee-Yong Park 3 , Kyung Chan Park 2 , Young Il Yeom 1, 5 1 Biotherapeutics Translational Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Daejeon 34141, Korea 2 Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Daejeon 34141, Korea 3 School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea 4 Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea 5 Department of Functional Genomics, University of Science and Technology, Daejeon 34113, Korea Correspondence to: Kyung Chan Park, email: kpark@kribb.re.kr Young Il Yeom, email: yeomyi@kribb.re.kr Zee-Yong Park, email: zeeyong@gist.ac.kr Keywords: PKM2, AKT, IGF-1, phosphorylation of PKM2, STAT5 Received: September 30, 2015 Accepted: June 04, 2016 Published: June 20, 2016 ABSTRACT Pyruvate kinase muscle type 2 (PKM2) exhibits post-translational modifications in response to various signals from the tumor microenvironment. Insulin-like growth factor 1 (IGF-1) is a crucial signal in the tumor microenvironment that promotes cell growth and survival in many human cancers. Herein, we report that AKT directly interacts with PKM2 and phosphorylates it at Ser-202, which is essential for the nuclear translocation of PKM2 protein under stimulation of IGF-1. In the nucleus, PKM2 binds to STAT5A and induces IGF-1-stimulated cyclin D1 expression, suggesting that PKM2 acts as an important factor inducing STAT5A activation under IGF-1 signaling. Concordantly, overexpression of STAT5A in cells deficient in PKM2 expression failed to restore IGF-induced growth, whereas reconstitution of PKM2 in PKM2 knockdown cells restored the IGF-induced growth capacity. Our findings suggest a novel role of PKM2 in promoting the growth of cancers with dysregulated IGF/phosphoinositide 3-kinase/AKT signaling.