Eukaryotic Initiation Factor 2alpha Kinase Research Articles

A CASE REPORT ON WOLCOTT RALLISON SYNDROME

A Case Report of Wolcott–Rallison syndrome, it is a rare, autosomal recessive disorder with infancy-onset diabetes mellitus, multiple epiphyseal dysplasia, osteopenia, mental retardation or developmental delay, and hepatic and renal dysfunction as main clinical findings. Patients have most common history of consanguineous marriage. Patients with WRS have mutations in the EIF2AK3 gene, which encodes the eukaryotic translation initiation factor 2-alpha kinase 3. Most common cause of death is fulminant hepatitis in early childhood.The EIKF2AK3 gene codes for PERK (pancreatic endoplasmic reticulum kinase),an explanation for the spectrum of symptoms.PERK is associated with the activity of beta cells in the pancreas.A broad range of bodily systems is affected, including pancreas, kidney, liver,bone, and nervous system, because of deficient stress response to improperly folded proteins inside the endoplasmic reticulum. A two months old male child born out of non-consanguineous marriage, Hindu by religion, presented with complain of fever since 4 days, respiratory distress since 12 hours. Patient was admitted and on regular blood sugar screening on arrival was high. Repeat random blood sugar was also elevated.Arterial blood gas was done which was suggested metabolic acidosis.Due to persistent high blood sugar,insulin drip was started and HbA1c was done which was 11 gm% and other investigations done. Diagnosis of neonatal diabetes mellitus was kept and managed accordingly. Studies for other endocrinopathies and autoimmune disease done which was negative. Child was having normal growth and development according to age. Genetic studies for neonatal diabetes was planned and EIKF2AK3 gene mutation was found homozygous. Both the parents were heterozygous for the mutation. So diagnosis was kept and regular follow up was advised.Key-words:Infant,Neonatal Diabetes,Endocrinopathy

BRCA1 mediates protein homeostasis through the ubiquitination of PERK and IRE1.

Tumors with BRCA1 mutations have poor prognoses due to genomic instability. Yet this genomic instability has risks and BRCA1-deficient (def) cancer cells must develop pathways to mitigate these risks. One such risk is the accumulation of unfolded proteins in BRCA1-def cancers from increased mutations due to their loss of genomic integrity. Little is known about how BRCA1-def cancers survive their genomic instability. Here we show that BRCA1 is an E3 ligase in the endoplasmic reticulum (ER) that targets the unfolded protein response (UPR) stress sensors, Eukaryotic Translation Initiation Factor 2-alpha Kinase 3 (PERK) and Serine/Threonine-Protein Kinase/Endoribonuclease Inositol-Requiring Enzyme 1 (IRE1) for ubiquitination and subsequent proteasome-mediated degradation. When BRCA1 is mutated or depleted, both PERK and IRE1 protein levels are increased, resulting in a constitutively activated UPR. Furthermore, the inhibition of protein folding or UPR signaling markedly decreases the overall survival of BRCA1-def cancer cells. Our findings define a mechanism used by the BRCA1-def cancer cells to survive their increased unfolded protein burden which can be used to develop new therapeutic strategies to treat these cancers.

Bioinformatics analysis combined with experiments to verify potential autophagy genes in wound healing.

BackgroundThe skin is the most exposed tissue and has multiple functions. Wound healing is a major medical problem due to trauma and pathophysiological alterations suffered by patients. The aim of the present study was to search for potential autophagy genes associated with wound healing.MethodsThe GSE168760 dataset was obtained from the Gene Expression Omnibus (GEO) database, and sequencing results were obtained for 14 patient traumas at different time periods. Differentially expressed gene (DEG) analysis, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed. Immune cell and correlation analysis were performed for autophagy genes and DEGs. Peripheral blood was collected from patients at different time periods and Western blot (WB) assay was performed to verify autophagy genes.ResultsA total of 226 DEGs were screened on days 0, 7, and 14, of which 162 genes were upregulated and 64 genes were downregulated. Of these, eukaryotic translation initiation factor 2-alpha kinase 2 (EIF2AK2) and retinoblastoma 1 (RB1) were autophagy-associated genes. The DEGs were mainly involved in response to virus, cellular response to type I interferon Epstein-Barr virus infection, human papillomavirus infection, ribosome, hepatitis B and RIG-I-like. EIF2AK2 and RB1 showed positive correlation with some of the immune cells, and WB showed that EIF2AK2 and RB1 proteins were significantly increased with wound healing.ConclusionsThe comprehensive analysis of GEO data in the present study provides a new theoretical basis for the molecular pathogenesis of trauma healing and potential autophagy-related therapeutic targets.

Wolcott Rallison Syndrome: Beyond Neonatal Diabetes

Background: Wolcott–Rallison Syndrome (WRS) is a rare autosomal recessive disorder characterized by permanent neonatal diabetes mellitus, skeletal dysplasia, hepatic dysfunction, and other systemic associations. Clinical Description: A 3-month-old infant with a history of fever and poor oral intake presented with severe dehydration, acidosis and 3+ urine ketones and was diagnosed to have sepsis and diabetic ketoacidosis (DKA). He also developed acute kidney injury (AKI) with blood urea 118 mg/dL and serum creatinine 1.5 mg/dL. Management: The child was ventilated, stabilized, and managed for DKA with fluids and insulin as per guidelines. AKI was managed with peritoneal dialysis. Genetic analysis revealed homozygous mutation in eukaryotic translation initiation factor 2-alpha kinase 3 gene consistent with the diagnosis of WRS. A close follow-up was kept with regular screening for other associated manifestations. Central hypothyroidism was detected first followed by skeletal dysplasia and chronic kidney disease. Growth retardation and developmental delay are also present. Conclusion: Neonatal diabetes cases need an early genetic work up and watchful follow-up for the manifestation of other possible associated features.

Microcystin-LR induces ferroptosis in intestine of common carp (Cyprinus carpio)

Previous studies provide comprehensive evidence of the environmental hazards and intestinal toxicity of microcystin-LR (MC-LR) exposure. However, little is known about the mechanisms underlying the injury of intestine exposed to MC-LR. Juvenile common carp (Cyprinus carpio) were exposed to MC-LR (0 and 10 μg/L) for 15 days. The results suggest that organic anion-transporting polypeptides 3a1, 4a1, 2b1, and 1d1 mediate MC-LR entry into intestinal tissues. Lesion morphological features (vacuolization, deformation and dilation of the endoplasmic reticulum [ER], absence of mitochondrial cristae in mid-intestine), up-regulated mRNA expressions of ER stress (eukaryotic translation initiation factor 2-alpha kinase 3, endoplasmic reticulum to nucleus signaling 1, activating transcription factor [ATF] 6, ATF4, DNA damage-inducible transcript 3), iron accumulation, and down-regulated activity of glutathione peroxidase (GPx) and glutathione (GSH) content were all typical characteristics of ferroptosis in intestinal tissue following MC-LR exposure. GSH levels in intestinal tissue corroborated as the most influential GSH/GPx 4- related metabolic pathway in response to MC-LR exposure. Verrucomicrobiota, Planctomycetes, Bdellovibrionota, Firmicutes and Cyanobacteria were correlated with the ferroptosis-related GSH following MC-LR exposure. These findings provide new perspectives of the ferroptosis mechanism of MC-LR-induced intestinal injury in the common carp.

Pulmonary veno-occlusive disease in childhood-a rare disease not to be missed.

Pulmonary veno-occlusive disease (PVOD) is a rare disease leading to pulmonary hypertension and potentially death related to right heart failure and/or respiratory insufficiency. Clinical symptoms are heterogenous and nonspecific: fatigue, decreased exercise tolerance, shortness of breath on exertion, cough, dizziness, chest pain with exercise, palpitations, syncope, as well as nonspecific symptoms such as headache, poor appetite, pallor or perioral cyanosis. Mutations in the EIF2AK4 (eukaryotic translation initiation factor 2-alpha kinase 4) have been recently described, other risk factors include exposure to organic solvent and trichloroethylene, tobacco exposure and chemotherapy. Echocardiography helps to estimate right ventricular systemic pressure, but further diagnostic workup includes cardiac catheterization to confirm pulmonary hypertension and increased pulmonary vascular resistance. High-resolution computed tomography reveals typical findings: centrilobular ground-glass nodules or opacities, septal lines, thickened interlobular septa, mosaic perfusion, and lymphadenopathy. Histology remains the gold standard, but carries risks for the patient. Proper workup is essential in order to avoid incorrect diagnosis. Pulmonary hypertension targeted treatment has been used in patients with PVOD, however, experience is limited, vasodilatory effects on pulmonary vasculature may lead to deterioration of the patients and should be used with great caution. Lung transplantation is currently the only valid treatment option for patients with PVOD. With prolonged waiting time and progression of the disease mechanical support could be considered.

The PKR/P38/RIPK1 Signaling Pathway as a Therapeutic Target in Alzheimer's Disease.

Neuropathological lesions in Alzheimer’s disease (AD) include amyloid plaques formed by the accumulation of amyloid peptides, neurofibrillary tangles made of hyperphosphorylated tau protein, synaptic and neuronal degenerations, and neuroinflammation. The cause of AD is unknown, but according to the amyloid hypothesis, amyloid oligomers could lead to the activation of kinases such as eukaryotic translation initiation factor 2-alpha kinase 2 (PKR), p38, and receptor-interacting serine/threonine-protein kinase 1 (RIPK1), which all belong to the same stress-activated pathway. Many toxic kinase activations have been described in AD patients and in experimental models. A p38 mitogen-activated protein kinase inhibitor was recently tested in clinical trials but with unsuccessful results. The complex PKR/P38/RIPK1 (PKR/dual specificity mitogen-activated protein kinase kinase 6 (MKK6)/P38/MAP kinase-activated protein kinase 2 (MK2)/RIPK1) is highly activated in AD brains and in the brains of AD transgenic animals. To delineate the implication of this pathway in AD, we carried out a search on PubMed including PKR/MKK6/p38/MK2/RIPK1, Alzheimer, and therapeutics. The involvement of this signaling pathway in the genesis of AD lesions, including Aβ accumulations and tau phosphorylation as well as cognitive decline, is demonstrated by the reports described in this review. A future combination strategy with kinase inhibitors should be envisaged to modulate the consequences for neurons and other brain cells linked to the abnormal activation of this pathway.

The Role of Oxymatrine in Amelioration of Acute Lung Injury Subjected to Myocardial I/R by Inhibiting Endoplasmic Reticulum Stress in Diabetic Rats.

Background Oxymatrine (OMT) is the primary pharmacological component of Sophora flavescens Aiton., which has been shown to possess potent antifibrotic, antioxidant, and anti-inflammatory activities. The aim of the present study was to clarify the protective mechanism of OMT on acute lung injury (ALI) subjected to myocardial ischemia/reperfusion (I/R). Methods A myocardial I/R-induced ALI model was achieved in diabetic rats by occluding the left anterior descending coronary artery for 1 h, followed by reperfusion for 1 h. The levels of inflammatory factors (tumor necrosis factor-α, interleukin- (IL-) 6, and IL-17) in bronchoalveolar lavage fluid were assessed using commercially available kits. The index of myocardial injury, including the detection of cardiac troponin I (cTnI), cardiac troponin T (cTnT), lactate dehydrogenase (LDH), and creatine kinase-MB (CK-MB), was also determined using commercially available kits. Hematoxylin and eosin staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling were used to identify histological changes. The expression levels of endoplasmic reticulum chaperone BiP (GRP78), DNA damage-inducible transcript 3 protein (CHOP), eukaryotic translation initiation factor 2-alpha kinase 3 (PERK), inositol dependent enzyme 1α (IRE1α), ATF6, caspase-3, -9, and-12, Bcl-2, and Bax were determined by Western blotting. The mRNA expression levels of GRP78 and CHOP were detected by reverse transcription-quantitative PCR. Results Myocardial I/R increased the levels of cTnI, cTnT, LDH, and CK-MB in diabetic rats. Damaged and irregularly arranged myocardial cells were also observed, as well as more serious ALI with higher lung injury scores and WET/DRY ratios and lower PaO2. Moreover, the expression of key proteins of endoplasmic reticulum stress (ERS) was increased by I/R injury, including phosphorylated- (p-) PERK, p-IRE1ɑ, and ATF6, as well as decreased levels of apoptosis. These effects were all significantly reversed by OMT treatment. Conclusions OMT protects against ALI subjected to myocardial I/R by inhibiting ERS in diabetic rats.

A novel splice site indel alteration in the EIF2AK3 gene is responsible for the first cases of Wolcott-Rallison syndrome in Hungary

BackgroundWolcott-Rallison Syndrome (WRS) is a rare autosomal recessive disease that is the most common cause of neonatal diabetes in consanguineous families. WRS is caused by various genetic alterations of the Eukaryotic Translation Initiation Factor 2-Alpha Kinase 3 (EIF2AK3) gene.MethodsGenetic analysis of a consanguineous family where two children were diagnosed with WRS was performed by Sanger sequencing. The altered protein was investigated by in vitro cloning, expression and immunohistochemistry.ResultsThe first cases in Hungary, − two patients in one family, where the parents were fourth-degree cousins - showed the typical clinical features of WRS: early onset diabetes mellitus with hyperglycemia, growth retardation, infection-induced multiple organ failure. The genetic background of the disease was a novel alteration in the EIF2AK3 gene involving the splice site of exon 11– intron 11–12 boundary: g.53051_53062delinsTG. According to cDNA sequencing this created a new splice site and resulted in a frameshift and the development of an early termination codon at amino acid position 633 (p.Pro627AspfsTer7). Based on in vitro cloning and expression studies, the truncated protein was functionally inactive. Immunohistochemistry revealed that the intact protein was absent in the islets of pancreas, furthermore insulin expressing cells were also dramatically diminished. Elevated GRP78 and reduced CHOP protein expression were observed in the liver.ConclusionsThe novel genetic alteration causing the absence of the EIF2AK3 protein resulted in insufficient handling of severe endoplasmic reticulum stress, leading to liver failure and demise of the patients.

Induction of the unfolded protein response (UPR) suppresses porcine reproductive and respiratory syndrome virus (PRRSV) replication

Replication of most RNA viruses is closely associated with the endoplasmic reticulum (ER) within permissive cells. As such, viruses often induce tremendous amounts of stress on cells during viral replication. To cope with the stress, cells initiate the unfolded protein response (UPR) to promote cellular survival. Porcine reproductive and respiratory syndrome virus (PRRSV), an economically important swine pathogen, was previously shown to induce cellular stress at late stages post-infection resulting in the formation of stress granules (SGs). Here in this study, we demonstrate that PRRSV also induces additional cellular response pathways, including the UPR. Confocal microscopy analysis demonstrated significant morphological changes in the ER of PRRSV-infected cells, indicative of pronounced ER stress. Further investigation revealed induction of all three branches of the UPR, including eukaryotic translation initiation factor 2-alpha kinase 3 (PERK), serine-threonine protein kinase/endoribonuclease (IRE1), and cyclic AMP-dependent transcription factor (ATF6). Activation of these sensors resulted in significant transcriptional upregulation of downstream UPR effectors. Additionally, UPR activation was shown to be detrimental to PRRSV replication, as treatment of cells with chemical ER stress inducers potently suppressed viral replication and RNA synthesis. Further investigation into the molecular mechanisms of UPR suppression of PRRSV replication revealed that PERK exacerbates the PRRSV-induced cytokine response. Collectively, these results demonstrate that PRRSV infection induces UPR activation through all three branches, and that UPR signaling may play a role in PRRSV pathogenesis. The results of this study further our understanding of the underlying molecular mechanisms of PRRSV replication and host-pathogen interactions.

The PKR-Like Endoplasmic Reticulum Kinase Promotes the Dissemination of Myc-Induced Leukemic Cells.

Hyperactive oncogenic Myc stimulates protein synthesis that induces the unfolded protein response, which requires the function of the eukaryotic translation initiation factor 2-alpha kinase 3, also known as protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK). Activated PERK acts to limit mRNA translation, enable proper protein folding, and restore the homeostasis in the endoplasmic reticulum. Given that Myc activation contributes to many types of lymphoid and myeloid human leukemias, we used a mouse model to examine the importance of PERK in development and progression of Myc-induced leukemias. We found that genetic ablation of Perk does not suppress the generation of the leukemic cells in the bone marrow. However, the cell-autonomous Perk deficiency restricts the dissemination of leukemic cells into peripheral blood, lymph nodes, and vital peripheral organs. Whereas the loss of the IFNAR1 chain of type I IFN receptor stimulated leukemia, Perk ablation did not stabilize IFNAR1, suggesting that PERK stimulates the leukemic cells' dissemination in an IFNAR1-independent manner. We discuss the rationale for using PERK inhibitors against Myc-driven leukemias. IMPLICATIONS: The role of PERK in dissemination of Myc-induced leukemic cells demonstrated in this study argues for the use of PERK inhibitors against leukemia progression.

A Novel SNP in EIF2AK4 Gene Is Associated with Thermal Tolerance Traits in Chinese Cattle.

Simple SummaryChina harbors two lineages of cattle (Bos taurus and Bos indicus) that display pronounced geographical distribution differences. Northern Chinese cattle predominantly belong to B. taurus and southern Chinese cattle belong to B. indicus. Both B. taurus and B. indicus contribute to the admixture of cattle in central China. Thermal stress induces oxidative stress and DNA damage in mammals. In general, B. indicus are more resistant to thermal stress than B. taurus. Eukaryotic translation initiation factor 2-alpha kinase 4 (EIF2AK4), which pertains to the family of serine–threonine kinase, is a candidate gene for thermal stress. However, the effects of the bovine EIF2AK4 gene on the thermal tolerance traits of Chinese cattle breeds remain unknown. Our results suggest that a variant of the EIF2AK4 gene is associated with thermal tolerance traits in Chinese cattle.Eukaryotic translation initiation factor 2-alpha kinase 4 (EIF2AK4, also known as GCN2), which pertains to the family of serine–threonine kinase, is involved in oxidative stress and DNA damage repair. A missense single-nucleotide polymorphism (SNP) (NC_037337.1 g.35615224 T > G) in exon 6 of the EIF2AK4 gene which encodes a p.Ile205Ser substitution was observed in the Bovine Genome Variation Database and Selective Signatures (BGVD). The purpose of the current study is to determine the allelic frequency distribution of the locus and analyze its association with thermal tolerance in Chinese indigenous cattle. In our study, the allelic frequency distribution of the missense mutation (NC_037337.1 g.35615224 T > G) in Chinese cattle was analyzed by sequencing 1105 individuals of 37 breeds including 35 Chinese indigenous cattle breeds and two exotic breeds. In particular, association analysis was carried out between the genotypes and three environmental parameters including annual mean temperature (T), relative humidity (RH), and temperature–humidity index (THI). The frequency of the mutant allele G (NC_037337.1 g.35615224 T > G) gradually decreased from the southern cattle groups to the northern cattle groups, whereas the frequency of the wild-type allele T showed an opposite pattern, consistent with the distribution of indicine and taurine cattle in China. In accordance with the association analysis, genotypes were significantly associated with T (P < 0.01), RH (P < 0.01), and THI (P < 0.01), suggesting that the cattle with genotype GG were found in regions with higher T, RH, and THI. Thus, our results suggest that the mutation (NC_037337.1 g.35615224 T > G) of the EIF2AK4 gene is associated with thermal tolerance traits in Chinese cattle.

EIF2AK3 novel mutation in a child with early-onset diabetes mellitus, a case report

BackgroundWolcott-Rallison syndrome (WRS) is caused by a biallelic mutation in the gene encoding eukaryotic translation initiation factor 2-alpha kinase 3 (EIF2AK3) on chromosome 2p11.2. This condition is characterized by permanent early-onset diabetes mellitus, epiphyseal dysplasia, and hepatic dysfunction. We report a patient with WRS born to a consanguineous marriage due to a novel biallelic frameshift mutation in the EIF2AK3 gene.Case presentationOur patient was a 2-year-and-6-month-old Yemeni girl born to consanguineous parents who was diagnosed with neonatal diabetes at 20 days of age. She presented with chronic diarrhea and liver dysfunction. The child was normocephalic and exhibited failure to thrive and hepatomegaly with no skeletal deformities. Further investigations revealed microcytic anemia, liver impairment and primary hypothyroidism. Genetic testing confirmed the diagnosis of WRS via identification of a novel biallelic frameshift mutation in the EIF2AK3 gene. During her hospital stay, she went into septic shock and developed multi-organ failure, including fulminant hepatic failure. She unfortunately died within 2 weeks of her hospital stay.ConclusionsWolcott-Rallison syndrome is recognized as the most common cause of early-onset diabetes in infants born to consanguineous marriages. Screening for genetic mutations in EIF2AK3 is recommended for establishing early diagnosis, providing genetic counselling, and predicting the development of additional clinical features, most importantly hepatic failure. Hence, this screening is important for guiding optimal management and improving patient outcome.

Altered unfolded protein response and proteasome impairment in pseudoexfoliation pathogenesis

Pseudoexfoliation (PEX), an ocular disorder involving deposition of proteinaceous fibrils on the surface of anterior eye tissues, is a major contributing factor to worldwide glaucoma. Excessive production and accumulation of fibrillar materials in PEX could be an indication of proteostasis imbalance. This study aims at investigating the differential expression of various genes involved in unfolded protein response and ubiquitin proteasome pathway in pseudoexfoliation (PEX) patients compared to non-PEX controls using lens capsule tissue as the study material. The custom RT2 Profiler PCR array was used to identify a set of stress-related candidate genes that were differentially expressed in PEX. The expression of the highly deregulated genes was validated by qRT-PCR and subsequently their protein expression was checked through immunoblotting and immunostaining. Proteasome-Glo based assay and TUNEL assay were employed to detect specific proteasomal activity and apoptotic activity, respectively in the study subjects. Increased ER stress markers, Synoviolin1, Eukaryotic initiation factor 2-alpha kinase 3, DnaJ (Hsp40) homolog, subfamily B, member 11, Caspase 12, Heat shock 70 kDa protein 5, Heat shock 60 kDa protein 1 and Calnexin were observed in the lens capsule of PEX individuals compared to age-matched controls. On the other hand, increased ubiquitin B mRNA expression followed by significant downregulation of proteasome subunits; 26 S proteasome non-ATPase regulatory subunit 1, and proteasome subunit alpha-type 5 was found in pseudoexfoliation syndrome (PEXS) individuals. Decrease in chymotrypsin-like proteasome activity and increased apoptosis were also observed in PEX subjects.The present findings provide evidence for alterations in endoplasmic reticulum–related stress response and ubiquitin proteasome function in lens capsule of PEX individuals. Altogether, our study has identified deregulated expression of candidate genes in ER-UPR pathway and implicates proteasome impairment as a causative factor in PEX pathogenesis.

Molecular evolution and functional divergence of eukaryotic translation initiation factor 2-alpha kinases.

Eukaryotic translation initiation factor 2-alpha kinase (EIF2AK) proteins inhibit protein synthesis at translation initiation level, in response to various stress conditions, including oxidative stress, heme deficiency, osmotic shock, and heat shock. Origin and functional diversification of EIF2AK sequences remain ambiguous. Here we determine the origin and molecular evolution of EIF2AK proteins in lower eukaryotes and studied the molecular basis of divergence among sub-family sequences. Present work emphasized primitive origin of EIF2AK4 sub-family gene in lower eukaryotes of protozoan lineage. Phylogenetic analysis supported common origin and sub-family based classification of EIF2AKs. Functional divergence studies across sub-families revealed several putative amino acid sites, which assist in altered protein interactions of kinase domains. The data can facilitate designing site-directed experimental studies aiming at elucidating diverse functional aspects of kinase domains regarding down-regulation of protein synthesis.

Genetic influences on cognition in progressive supranuclear palsy.

Cognitive dysfunction is common in progressive supranuclear palsy, but the influence of genetics on cognition in this disorder has not been well studied. The objective of this study was to investigate the effect of genes previously identified as risk alleles, including microtubule-associated protein tau, myelin-associated oligodendrocyte basic protein, eukaryotic translation initiation factor 2-alpha kinase 3, and syntaxin 6, as well as apolipoprotein E, on cognitive function in progressive supranuclear palsy. The sample was composed of 305 participants who met criteria for possible or probable progressive supranuclear palsy. Genetic information was determined by TaqMan genotyping assays. A neuropsychological battery was administered to all study participants. Measures included in the battery evaluated for general cognition, executive function, memory, attention, language, and visuospatial ability. Cognition did not vary significantly between individuals homozygous or heterozygous for the microtubule-associated protein tau H1 haplotype. However, cognition varied significantly at the subhaplotype level, with carriers of the microtubule-associated protein tau rs242557/A allele, which marks the H1c subhaplotype, performing better than noncarriers on measures of general cognitive function, executive function, and attention. No associations were found for other genes. The results of the current study indicate that variations in microtubule-associated protein tau influence cognition in progressive supranuclear palsy. Although the H1c-specific rs242557/A allele is a risk factor for progressive supranuclear palsy, carriers of this allele may exhibit better cognition than non-carriers in patients with the atypical parkinsonian syndrome. Further studies are needed. © 2017 International Parkinson and Movement Disorder Society.

A Genotype-First Approach for Clinical and Genetic Evaluation of Wolcott-Rallison Syndrome in a Large Cohort of Iranian Children With Neonatal Diabetes.

Wolcott-Rallison syndrome (WRS) is an extremely rare autosomal recessive condition, characterized by permanent neonatal diabetes mellitus (PNDM) associated with skeletal dysplasia, growth retardation and liver dysfunction. WRS is caused by biallelic mutations in the gene encoding eukaryotic translation initiation factor 2alpha kinase 3 (EIF2AK3). As part of a comprehensive study on clinical and genetic investigation of neonatal diabetes in an Iranian population, 60 unrelated Iranian subjects referred with PNDM were analyzed. All the probands were screened for KCNJ11, INS, ABCC8 and EIF2AK3 using a polymerase chain reaction-based sequencing approach. We identified 9 different variants in EIF2AK3 in 11 unrelated Iranian probands, of which 5 variants were shown to be novel and not reported previously. The diagnosis of WRS was made by molecular genetic testing and confirmed by clinical re-evaluation of the subjects. Clinical follow up of the affected individuals shows that in at least some of them, PNDM was associated with short stature, failure to thrive, neurodevelopmental delay, epilepsy and hepatic and renal dysfunction. There was a strong family history of neonatal diabetes in the families of the probands with a high mortality rate. WRS is a common cause of PNDM in children of consanguineous parents. Furthermore, clinical diagnosis of WRS would have been delayed or possibly missed without genetic testing because this study shows that the associated features of WRS might be obscured by a diagnosis of PNDM. Therefore EIF2AK3 should be considered for any infant and young child with PNDM, particularly if the parents are related.

Abstract B11: Proteomic analysis of serum-derived exosomes: Identification of novel protein signature associated with African-American prostate cancer

Abstract African-American men face a stark prostate cancer (PCA)-related health disparity in the United States, with the highest incidence and mortality rate compared to all other races. African-American men are more frequently diagnosed with high Gleason grade PCA at a younger age and with a poorer prognosis. In the past three decades, there has been little improvement in reducing this health disparity, demanding additional and innovative measures. Here, we focused on the identification of novel serum exosome-based ‘protein signature' for potential use in the early detection and better prognosis of PCA in African-American men. Analysis of clinical serum samples showed that compared to healthy individuals, exosome concentration was increased by ~3.2 fold (p=0.047) in the sera of African-American men with PCA (Gleason score 7). Mass spectrometry based proteomic analysis of serum exosomal proteins showed 55 common proteins in African-American men with PCA (PAA) and normal African-American men without PCA (NAA). Interestingly, 7 unique proteins [Isoform 2 of Coiled-coil and C2 domain-containing protein 1A, Keratin type I cytoskeletal 10, UPF0728 protein C10orf53, DnaJ homolog subfamily C member 13, Prothrombin, Apolipoprotein(a) and Coiled-coil domain-containing protein 172] were present only in PAA, and not in NAA. The top upregulated proteins in PAA, as compared to NAA, included Keratin type II cytoskeletal 2 epidermal (64 fold), Serum amyloid P-component (39 fold), Keratin type II cytoskeletal 1 (13 fold), Keratin type I cytoskeletal 9 (12 fold), Isoform 2 of Filamin-A (2.6 fold), Isoform 3 of Vitamin D-binding protein (2.4 fold), Ig kappa chain V-II region Cum (2.4 fold) and Isoform 2 of Eukaryotic translation initiation factor 2-alpha kinase 4 (1.8 fold). The top downregulated proteins in PAA included Apolipoprotein A-I (0.04 fold), Complement component C8 alpha chain (0.07 fold), Plasminogen (0.08 fold), Complement component C7 (0.1 fold), and Isoform 2 of Inter-alpha-trypsin inhibitor heavy chain H4 (0.2 fold). Importantly, Ingenuity pathway analysis (IPA) showed that the proteins detected by proteomic analysis in PAA exosomes belonged to the acute-phase response signaling pathway proteins, which have been reported for their potential use as diagnostic biomarkers for PCA. Next, we compared proteins loaded in PAA serum exosomes with Gleason score-matched Caucasian PCA (PCC) serum exosomes. PAA and PCC exosomes shared 57 common proteins, while PAA serum exosomes showed six unique proteins (Isoform 2 of Coiled-coil and C2 domain-containing protein 1A, UPF0728 protein C10orf53, Ig kappa chain V-I region EU, Ig kappa chain V-II region Cum, DnaJ homolog subfamily C member 13, Coiled-coil domain-containing protein 172). Furthermore, top upregulated proteins in PAA, as compared to PCC, included Isoform 2 of Eukaryotic translation initiation factor 2-alpha kinase 4 (34 fold), Keratin type I cytoskeletal 10 (10 fold), SCO-spondin (5.3 fold), Serum amyloid P-component (4 folds) and Apolipoprotein(a) (3.9 fold). The top down regulated proteins in PAA, as compared to PCC, included Ig lambda chain V-I region WAH (0.02 fold), alpha-1B-glycoprotein (0.03 fold), Apolipoprotein A-I (0.03 fold), Complement component C8 alpha chain (0.06 fold) and Isoform 2 of Haptoglobin (0.09 fold). Overall, we have identified several unique and differentially expressed proteins in the serum exosomes of African-American men with PCA. These results also support further development and application of serum exosome-based proteomic signature for early detection and better prognosis of PCA in African- American men. Citation Format: Gagan Deep, Gatikrushna Panigrahi, Rakesh Singh, Kathleen Torkko, Adrie Bokhoven. Proteomic analysis of serum-derived exosomes: Identification of novel protein signature associated with African-American prostate cancer. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B11.

Human Protein Kinases and Obesity.

The action of protein kinases and protein phosphatases is essential for multiple physiological responses. Each protein kinase displays its own unique substrate specificity, and a regulatory mechanism that may be modulated by association with other proteins. Protein kinases are classified by the target amino acid in their substrates. Some protein kinases can phosphorylate both serine/threonine, as well as tyrosine residues. This group of kinases has been known as dual specificity kinases. Unlike the dual specificity kinases, a heterogeneous group of protein phosphatases are known as dual-specificity phosphatases. These phosphatases remove phosphate groups from tyrosine and serine/threonine residues on their substrate. Dual-specificity phosphatases are important signal transduction enzymes that regulate various cellular processes in coordination with protein kinases. The protein kinase-phosphoproteins interactions play an important role in obesity . In obesity, the pro- and anti-inflammatory effects of adipokines and cytokines through intracellular signaling pathways mainly involve the nuclear factor kappa B (NF-kappaB) and the c-Jun N-terminal kinase (JNK) systems as well as the inhibitor of kappaB-kinase beta (IKK beta). Impairment of insulin signaling in obesity is largely mediated by the activation of the IKKbeta and the JNK. Furthermore, oxidative stress and endoplasmic reticulum (ER) stress activate the JNK pathway which suppresses insulin biosynthesis. Additionally, obesity-activated calcium/calmodulin dependent-protein kinase II/p38 suppresses insulin-induced protein kinase B phosphorylation by activating the ER stress effector, activating transcription factor-4. Obese adults with vascular endothelial dysfunction have greater endothelial cells activation of unfolded protein response stress sensors, RNA-dependent protein kinase-like ER eukaryotic initiation factor-2alpha kinase (PERK) and activating transcription factor-6. The transcriptional regulation of adipogenesis in obesity is influenced by AGC (protein kinase A (PKA), PKG, PKC) family signaling kinases. Obesity may induce systemic oxidative stress and increase reactive oxygen species in adipocytes. Increase in intracellular oxidative stress can promote PKC-beta activation. Activated PKC-beta induces growth factor adapter Shc phosphorylation. Shc-generated peroxides reduce mitochondrial oxygen consumption and enhances triglyceride accumulation. Obesity is fundamentally caused by cellular energy imbalance and dysregulation. Like adenosine monophosphate (AMP)-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR), N-terminal Per-ARNT-Sim (PAS) kinase are nutrient responsive protein kinases and important for proper regulation of glucose metabolism in mammals at both the hormonal and cellular level. Defective responses of AMPK to leptin may contribute to resistance to leptin action on food intake and energy expenditure in obese states.

Lithocholic acid induces endoplasmic reticulum stress, autophagy and mitochondrial dysfunction in human prostate cancer cells.

Lithocholic acid (LCA) is a secondary bile acid that is selectively toxic to human neuroblastoma, breast and prostate cancer cells, whilst sparing normal cells. We previously reported that LCA inhibited cell viability and proliferation and induced apoptosis and necrosis of androgen-dependent LNCaP and androgen-independent PC-3 human prostate cancer cells. In the present study, we investigated the roles of endoplasmic reticulum (ER) stress, autophagy and mitochondrial dysfunction in the toxicity of LCA in PC-3 and autophagy deficient, androgen-independent DU-145 cells. LCA induced ER stress-related proteins, such as CCAAT-enhancer-binding protein homologous protein (CHOP), and the phosphorylation of eukaryotic initiation factor 2-alpha (p-eIF2α) and c-Jun N-terminal kinases (p-JNK) in both cancer cell-types. The p53 upregulated modulator of apoptosis (PUMA) and B cell lymphoma-like protein 11 (BIM) levels were decreased at overtly toxic LCA concentrations, although PUMA levels increased at lower LCA concentrations in both cell lines. LCA induced autophagy-related conversion of microtubule-associated proteins 1A/1B light chain 3B (LC3BI–LC3BII), and autophagy-related protein ATG5 in PC-3 cells, but not in autophagy-deficient DU-145 cells. LCA (>10 µM) increased levels of reactive oxygen species (ROS) concentration-dependently in PC-3 cells, whereas ROS levels were not affected in DU-145 cells. Salubrinal, an inhibitor of eIF2α dephosphorylation and ER stress, reduced LCA-induced CHOP levels slightly in PC-3, but not DU-145 cells. Salubrinal pre-treatment increased the cytotoxicity of LCA in PC-3 and DU-145 cells and resulted in a statistically significant loss of cell viability at normally non-toxic concentrations of LCA. The late-stage autophagy inhibitor bafilomycin A1 exacerbated LCA toxicity at subtoxic LCA concentrations in PC-3 cells. The antioxidant α-tocotrienol strongly inhibited the toxicity of LCA in PC-3 cells, but not in DU-145 cells. Collectively, although LCA induces autophagy and ER stress in PC-3 cells, these processes appear to be initially of protective nature and subsequently consequential to, but not critical for the ROS-mediated mitochondrial dysfunction and cytotoxicity of LCA. The full mechanism of LCA-induced mitochondrial dysfunction and cytotoxicity in the similarly sensitive DU-145 cells remains to be elucidated.