Novel Tyrosine Kinase-Mediated Phosphorylation With Dual Specificity Plays a Key Role in the Modulation of Streptococcus pyogenes Physiology and Virulence

Streptococcus pyogenes (Group A Streptococcus, GAS) genomes do not contain a gene encoding a typical bacterial-type tyrosine kinase (BY-kinase) but contain an orphan gene-encoding protein Tyr-phosphatase (SP-PTP). Hence, the importance of Tyr-phosphorylation is underappreciated and not recognized for its role in GAS pathophysiology and pathogenesis. The fact that SP-PTP dephosphorylates Abl-tyrosine kinase-phosphorylated myelin basic protein (MBP), and SP-STK (S. pyogenes Ser/Thr kinase) also autophosphorylates its Tyr101-residue prompted us to identify a putative tyrosine kinase and Tyr-phosphorylation in GAS. Upon a genome-wide search of kinases possessing a classical Walker motif, we identified a non-canonical tyrosine kinase M5005_Spy_1476, a ∼17 kDa protein (153 aa) (SP-TyK). The purified recombinant SP-TyK autophosphorylated in the presence of ATP. In vitro and in vivo phosphoproteomic analyses revealed two key phosphorylated tyrosine residues located within the catalytic domain of SP-TyK. An isogenic mutant lacking SP-TyK derived from the M1T1 strain showed a retarded growth pattern. It displayed defective cell division and long chains with multiple parallel septa, often resulting in aggregates. Transcriptomic analysis of the mutant revealed 287 differentially expressed genes responsible for GAS pathophysiology and pathogenesis. SP-TyK also phosphorylated GAS CovR, WalR, SP-STP, and SDH/GAPDH proteins with dual specificity targeting their Tyr/Ser/Thr residues as revealed by biochemical and mass-spectrometric-based phosphoproteomic analyses. SP-TyK-phosphorylated CovR bound to PcovR efficiently. The mutant displayed sustained release of IL-6 compared to TNF-α during co-culturing with A549 lung cell lines, attenuation in mice sepsis model, and significantly reduced ability to adhere to and invade A549 lung cells and form biofilms on abiotic surfaces. SP-TyK, thus, plays a critical role in fine-tuning the regulation of key cellular functions essential for GAS pathophysiology and pathogenesis through post-translational modifications and hence, may serve as a promising target for future therapeutic developments.

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Laforin, a dual-specificity phosphatase involved in Lafora disease, is phosphorylated at Ser25 by AMP-activated protein kinase

Biochemical Journal ◽

10.1042/bj20110150 ◽

2011 ◽

Vol 439 (2) ◽

pp. 265-275 ◽

Cited By ~ 17

Author(s):

Carlos Romá-Mateo ◽

Maria del Carmen Solaz-Fuster ◽

José Vicente Gimeno-Alcañiz ◽

Vikas V. Dukhande ◽

Jordi Donderis ◽

...

Keyword(s):

Protein Kinase ◽

Neurodegenerative Disorder ◽

Critical Role ◽

Glycogen Metabolism ◽

Lafora Disease ◽

Gene Encoding ◽

Dual Specificity Phosphatase ◽

Progressive Myoclonus Epilepsy ◽

Dual Specificity ◽

Amp Activated Protein Kinase

Lafora progressive myoclonus epilepsy [LD (Lafora disease)] is a fatal autosomal recessive neurodegenerative disorder caused by loss-of-function mutations in either the EPM2A gene, encoding the dual-specificity phosphatase laforin, or the EPM2B gene, encoding the E3-ubiquitin ligase malin. Previously, we and others showed that laforin and malin form a functional complex that regulates multiple aspects of glycogen metabolism, and that the interaction between laforin and malin is enhanced by conditions activating AMPK (AMP-activated protein kinase). In the present study, we demonstrate that laforin is a phosphoprotein, as indicated by two-dimensional electrophoresis, and we identify Ser25 as the residue involved in this modification. We also show that Ser25 is phosphorylated both in vitro and in vivo by AMPK. Lastly, we demonstrate that this residue plays a critical role for both the phosphatase activity and the ability of laforin to interact with itself and with previously established binding partners. The results of the present study suggest that phosphorylation of laforin-Ser25 by AMPK provides a mechanism to modulate the interaction between laforin and malin. Regulation of this complex is necessary to maintain normal glycogen metabolism. Importantly, Ser25 is mutated in some LD patients (S25P), and our results begin to elucidate the mechanism of disease in these patients.

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Fine-tuning of substrate preferences of the Src-family kinase Lck revealed through a high-throughput specificity screen

eLife ◽

10.7554/elife.35190 ◽

2018 ◽

Vol 7 ◽

Cited By ~ 15

Author(s):

Neel H Shah ◽

Mark Löbel ◽

Arthur Weiss ◽

John Kuriyan

Keyword(s):

T Cell ◽

Tyrosine Kinase ◽

Cell Signaling ◽

High Throughput ◽

Tyrosine Kinases ◽

Catalytic Domain ◽

Surface Display ◽

Fine Tuning ◽

Tyrosine Kinase Domain ◽

T Cell Signaling

The specificity of tyrosine kinases is attributed predominantly to localization effects dictated by non-catalytic domains. We developed a method to profile the specificities of tyrosine kinases by combining bacterial surface-display of peptide libraries with next-generation sequencing. Using this, we showed that the tyrosine kinase ZAP-70, which is critical for T cell signaling, discriminates substrates through an electrostatic selection mechanism encoded within its catalytic domain (Shah et al., 2016). Here, we expand this high-throughput platform to analyze the intrinsic specificity of any tyrosine kinase domain against thousands of peptides derived from human tyrosine phosphorylation sites. Using this approach, we find a difference in the electrostatic recognition of substrates between the closely related Src-family kinases Lck and c-Src. This divergence likely reflects the specialization of Lck to act in concert with ZAP-70 in T cell signaling. These results point to the importance of direct recognition at the kinase active site in fine-tuning specificity.

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Transforming properties of chimeric TEL-JAK proteins in Ba/F3 cells

Blood ◽

10.1182/blood.v95.6.2076 ◽

2000 ◽

Vol 95 (6) ◽

pp. 2076-2083 ◽

Cited By ~ 106

Author(s):

Virginie Lacronique ◽

Anthony Boureux ◽

Richard Monni ◽

Stephanie Dumon ◽

Martine Mauchauffé ◽

...

Keyword(s):

Growth Factor ◽

Tyrosine Kinase ◽

Target Genes ◽

Catalytic Domain ◽

Dominant Negative ◽

Janus Kinase ◽

Cytokine Signaling ◽

Mobility Shift ◽

Gene Encoding ◽

Oligomerization Domain

Abstract The involvement of the cytokine signaling pathway in oncogenesis has long been postulated. Recently, rearrangements of the gene encoding the tyrosine Janus kinase 2 (JAK2) have been reported in human leukemias indicating a direct JAK-signal transduction and activator of transcription (STAT)-mediated leukemic process. The leukemia-associated TEL-JAK2 fusion protein is formed by the oligomerization domain of the translocated ets leukemia (TEL) protein fused to the catalytic domain of JAK2. TEL-mediated oligomerization results in a constitutive tyrosine kinase activity that, in turn, is able to confer growth factor independence to the murine hematopoietic interleukin-3 (IL-3)-dependent Ba/F3 cell line. Results of the present study indicate that fusion proteins containing the oligomerization domain of TEL and the tyrosine kinase domains of Jak1, Jak2, JAK3, or TYK2 share similar properties and are able to efficiently substitute for the survival and mitogenic signals controlled by IL-3, without concomitant activation of the IL-3 receptor. Electrophoretic mobility shift assays demonstrated Stat5 as the only activated Stat factor in TEL-Jak2- and TEL-Jak1-expressing cells, whereas other Stats, namely Stat1 and Stat3, could be detected in TEL-JAK3-, TEL-TYK2-, and also in TEL-ABL-expressing Ba/F3 cells. High levels of expression of the Stat5-target genes pim-1, osm, and Cis were observed in all the cytokine-independent cell lines. Furthermore, the expression of a dominant negative form of Stat5A markedly interfered with the growth factor independence process mediated by TEL-Jak2 in Ba/F3 cells. Because the BCR-ABL and TEL-PDGFβR oncoproteins also activate Stat5, activation of this factor should be a crucial step in activated tyrosine kinase-mediated leukemogenesis.

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Protein-tyrosine Kinase p72 syk Is Activated by Platelet Activating Factor in Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648987 ◽

1994 ◽

Vol 72 (06) ◽

pp. 937-941 ◽

Cited By ~ 7

Author(s):

Karim Rezaul ◽

Shigeru Yanagi ◽

Kiyonao Sada ◽

Takanobu Taniguchi ◽

Hirohei Yamamura

Keyword(s):

Tyrosine Kinase ◽

Tyrosine Phosphorylation ◽

Protein Tyrosine Kinase ◽

Kinase Inhibitor ◽

Critical Role ◽

Platelet Activating Factor ◽

Kinase Assay ◽

Potential Candidate ◽

Protein Tyrosine ◽

Induced Aggregation

SummaryIt has been demonstrated that activation of platelets by platelet-activating factor (PAF) results in a dramatic increase in tyrosine phosphorylation of several cellular proteins. We report here that p72 syk is a potential candidate for the protein-tyrosine phosphorylation following PAF stimulation in porcine platelets. Immunoprecipitation kinase assay revealed that PAF stimulation resulted in a rapid activation of p72 syk which peaked at 10 s. The level of activation was found to be dose dependent and could be completely inhibited by the PAF receptor antagonist, CV3988. Phosphorylation at the tyrosine residues of p72 syk coincided with activation of yllsyk. Pretreatment of platelets with aspirin and apyrase did not affect PAF induced activation of p72 syk .Furthermore, genistein, a potent protein-tyrosine-kinase inhibitor, diminished PAF-induced p72 syk activation and Ca2+ mobilization as well as platelet aggregation. These results suggest that p72 syk may play a critical role in PAF-induced aggregation, possibly through regulation of Ca2+ mobilization.

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Rhenium-188 labeled recombinant human plasminogen kringle5 (rhk5) and preliminary biodistribution

Nuklearmedizin ◽

10.3413/nukmed-0349-10-09 ◽

2011 ◽

Vol 50 (06) ◽

pp. 234-239 ◽

Cited By ~ 3

Author(s):

R. Guo ◽

Y. Ma ◽

R. Zhang ◽

S. Liang ◽

H. Shen ◽

...

Keyword(s):

Lung Adenocarcinoma ◽

Human Serum ◽

Critical Role ◽

Angiogenesis Inhibitor ◽

Simple Method ◽

Tumour Formation ◽

Human Plasminogen ◽

Specificity Of Binding ◽

A549 Lung

Summary Aim: Angiogenesis plays a critical role in tumour formation and metastasis. Suitable radiolabeled angiogenesis inhibitor can be used for noninvasive imaging of angiogenesis and radionuclide therapy. Here we prepare rhenium-188 labeled recombinant human plasminogen kringle5 (188Re-rhk5) in a convenient manner than evaluate its properties in A549 lung adenocarcinoma. Methods: 188Rerhk5 was obtained by conjugating His group at the C end of rhk5 with fac- [188Re(H2O)3(CO)3]+. Chelating efficiency of fac-[188Re(H2O)3(CO)3]+ and radiolabeling efficiency of 188Re-rhk5 were measured by radio thin-layer chromatography (RTLC). In vitro stability of 188Re-rhk5 was determined in human serum at 37°C and analyzed by RTLC. Competition test was also performed to verify the specificity of binding. A biodistribution study was carried out in nude mice bearing A549 lung adenocarcinoma. Results: 188Rerhk5 was obtained with a radiolabel efficiency of 66.1%, the radiochemical purity (RCP) can marreach 95.2% after purification. 188Re-rhk5 showed high stability in human serum, the RCP was more than 80% even 12 h after incubation. Competition test showed a high binding specificity. Furthermore, this radio-complex was excreted mainly through kidneys and showed specific tumour uptake in mice bearing A549 tumours. Conclusion: 188Re-rhk5 was prepared by a simple method. Preliminary biodistribution results showed its potential as an agent for possible tumour imaging, therapy and encouraged further investigation.

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Recent Advances on Epidermal Growth Factor Receptor as a Molecular Target for Breast Cancer Therapeutics

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520621666201222143213 ◽

2020 ◽

Vol 21 ◽

Author(s):

Swathi R. Shetty ◽

Ragini Yeeravalli ◽

Tanya Bera ◽

Amitava Das

Keyword(s):

Breast Cancer ◽

Epidermal Growth Factor Receptor ◽

Growth Factor ◽

Epidermal Growth Factor ◽

Tyrosine Kinase ◽

Critical Role ◽

Growth Factor Receptor ◽

Type I ◽

Egfr Inhibition ◽

Epidermal Growth

: Epidermal growth factor receptor (EGFR), a type-I transmembrane protein with intrinsic tyrosine kinase activity is activated by peptide growth factors such as EGF, epigen, amphiregulin, etc. EGFR plays a vital role in regulating cell growth, migration, and differentiation in various tissue-specific cancers. It has been reported to be overexpressed in lung, head, and neck, colon, brain, pancreatic, and breast cancer that trigger tumor progression and drug resistance. EGFR overexpression alters the signaling pathway and induces cell division, invasion, and cell survival. Our prior studies demonstrated that EGFR inhibition modulates chemosensitivity in breast cancer stem cells thereby serving as a potential drug target for breast cancer mitigation. Tyrosine kinase inhibitors (Lapatinib, Neratinib) and monoclonal antibodies (Trastuzumab) targeting EGFR have been developed and approved by the US FDA for clinical use against breast cancer. This review highlights the critical role of EGFR in breast cancer progression and enumerates the various approaches being undertaken to inhibit aggressive breast cancers by suppressing the downstream pathways. Further, the mechanisms of action of potential molecules at various stages of drug development as well as clinically approved drugs for breast cancer treatment are illustrated.

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Chemerin, A Novel Adipokine in the Regulation of Angiogenesis

Molecular Endocrinology ◽

10.1210/mend.24.4.9997 ◽

2010 ◽

Vol 24 (4) ◽

pp. 874-874

Author(s):

Kiymet Bozaoglu ◽

Joanne E. Curran ◽

Claire J. Stocker ◽

Mohamed S. Zaibi ◽

David Segal ◽

...

Keyword(s):

Endothelial Cells ◽

Mexican American ◽

Large Family ◽

Disease Status ◽

Human Endothelial Cells ◽

Gene Encoding ◽

The Metabolic Syndrome ◽

Heart Study ◽

A Genome ◽

Family Based

Abstract Context: Chemerin is a new adipokine associated with obesity and the metabolic syndrome. Gene expression levels of chemerin were elevated in the adipose depots of obese compared with lean animals and was markedly elevated during differentiation of fibroblasts into mature adipocytes. Objective: To identify factors that affect the regulation and potential function of chemerin using a genetics approach. Design, setting, patients and intervention: Plasma chemerin levels were measured in subjects from the San Antonio Family Heart Study (SAFHS), a large family-based genetic epidemiological study including 1354 Mexican American individuals. Individuals were randomly sampled without regard to phenotype or disease status. Main Outcome Measures: A genome wide association analysis using 542,944 SNPs in a subset of 523 of the same subjects was undertaken. The effect of chemerin on angiogenesis was measured using human endothelial cells and interstitial cells in co-culture in a specially formulated medium. Results: Serum chemerin levels were found to be highly heritable (h2 = 0.25; P = 1.4 x 10−9). The SNP showing strongest evidence of association (rs347344; P = 1.4 x 10−6) was located within the gene encoding EDIL3, which has a known role in angiogenesis. Functional angiogenesis assays in human endothelial cells confirmed that chemerin significantly mediated the formation of blood vessels to a similar extent as VEGF. Conclusion: Here we demonstrate for the first time that plasma chemerin levels are significantly heritable and identified a novel role for chemerin as a stimulator of angiogenesis.

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Genome-wide identification of cyclin-dependent kinase (CDK) genes affecting adipocyte differentiation in cattle

BMC Genomics ◽

10.1186/s12864-021-07653-8 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Cuili Pan ◽

Zhaoxiong Lei ◽

Shuzhe Wang ◽

Xingping Wang ◽

Dawei Wei ◽

...

Keyword(s):

Gene Family ◽

Expression Analysis ◽

Adipocyte Differentiation ◽

Bos Taurus ◽

Adipogenic Differentiation ◽

Critical Role ◽

Bos Indicus ◽

Specific Expression ◽

Genome Wide ◽

A Genome

Abstract Background Cyclin-dependent kinases (CDKs) are protein kinases regulating important cellular processes such as cell cycle and transcription. Many CDK genes also play a critical role during adipogenic differentiation, but the role of CDK gene family in regulating bovine adipocyte differentiation has not been studied. Therefore, the present study aims to characterize the CDK gene family in bovine and study their expression pattern during adipocyte differentiation. Results We performed a genome-wide analysis and identified a number of CDK genes in several bovine species. The CDK genes were classified into 8 subfamilies through phylogenetic analysis. We found that 25 bovine CDK genes were distributed in 16 different chromosomes. Collinearity analysis revealed that the CDK gene family in Bos taurus is homologous with Bos indicus, Hybrid-Bos taurus, Hybrid Bos indicus, Bos grunniens and Bubalus bubalis. Several CDK genes had higher expression levels in preadipocytes than in differentiated adipocytes, as shown by RNA-seq analysis and qPCR, suggesting a role in the growth of emerging lipid droplets. Conclusion In this research, 185 CDK genes were identified and grouped into eight distinct clades in Bovidae, showing extensively homology. Global expression analysis of different bovine tissues and specific expression analysis during adipocytes differentiation revealed CDK4, CDK7, CDK8, CDK9 and CDK14 may be involved in bovine adipocyte differentiation. The results provide a basis for further study to determine the roles of CDK gene family in regulating adipocyte differentiation, which is beneficial for beef quality improvement.

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Mode of Selection and Experimental Evolution of Antifungal Drug Resistance in Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/163.4.1287 ◽

2003 ◽

Vol 163 (4) ◽

pp. 1287-1298

Author(s):

James B Anderson ◽

Caroline Sirjusingh ◽

Ainslie B Parsons ◽

Charles Boone ◽

Claire Wickens ◽

...

Keyword(s):

Drug Resistance ◽

Pleiotropic Effect ◽

Antifungal Drug ◽

Recessive Mutation ◽

High Concentration ◽

Gene Encoding ◽

Antifungal Drug Resistance ◽

Degree Of Dominance ◽

A Genome ◽

Abc Transporter Genes

Abstract We show that mode of selection, degree of dominance of mutations, and ploidy are determining factors in the evolution of resistance to the antifungal drug fluconazole in yeast. In experiment 1, yeast populations were subjected to a stepwise increase in fluconazole concentration over 400 generations. Under this regimen, two mutations in the same two chromosomal regions rose to high frequency in parallel in three replicate populations. These mutations were semidominant and additive in their effect on resistance. The first of these mutations mapped to PDR1 and resulted in the overexpression of the ABC transporter genes PDR5 and SNQ2. These mutations had an unexpected pleiotropic effect of reducing the residual ability of the wild type to reproduce at the highest concentrations of fluconazole. In experiment 2, yeast populations were subjected to a single high concentration of fluconazole. Under this regimen, a single recessive mutation appeared in each of three replicate populations. In a genome-wide screen of ∼4700 viable deletion strains, 13 were classified as resistant to fluconazole (ERG3, ERG6, YMR102C, YMR099C, YPL056C, ERG28, OSH1, SCS2, CKA2, SML1, YBR147W, YGR283C, and YLR407W). The mutations in experiment 2 all mapped to ERG3 and resulted in the overexpression of the gene encoding the drug target ERG11, but not PDR5 and SNQ2. Diploid hybrids from experiments 1 and 2 were less fit than the parents in the presence of fluconazole. In a variation of experiment 2, haploids showed a higher frequency of resistance than diploids, suggesting that degree of dominance and ploidy are important factors in the evolution of antifungal drug resistance.

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A Genome-Wide Screen in Saccharomyces cerevisiae Reveals a Critical Role for Oxidative Phosphorylation in Cellular Tolerance to Lithium Hexafluorophosphate

Cells ◽

10.3390/cells10040888 ◽

2021 ◽

Vol 10 (4) ◽

pp. 888

Author(s):

Xuejiao Jin ◽

Jie Zhang ◽

Tingting An ◽

Huihui Zhao ◽

Wenhao Fu ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Oxidative Phosphorylation ◽

Cellular Response ◽

Critical Role ◽

Lithium Ion ◽

Deletion Mutants ◽

High Concentration ◽

Genome Wide ◽

A Genome ◽

Lithium Hexafluorophosphate

Lithium hexafluorophosphate (LiPF6) is one of the leading electrolytes in lithium-ion batteries, and its usage has increased tremendously in the past few years. Little is known, however, about its potential environmental and biological impacts. In order to improve our understanding of the cytotoxicity of LiPF6 and the specific cellular response mechanisms to it, we performed a genome-wide screen using a yeast (Saccharomyces cerevisiae) deletion mutant collection and identified 75 gene deletion mutants that showed LiPF6 sensitivity. Among these, genes associated with mitochondria showed the most enrichment. We also found that LiPF6 is more toxic to yeast than lithium chloride (LiCl) or sodium hexafluorophosphate (NaPF6). Physiological analysis showed that a high concentration of LiPF6 caused mitochondrial damage, reactive oxygen species (ROS) accumulation, and ATP content changes. Compared with the results of previous genome-wide screening for LiCl-sensitive mutants, we found that oxidative phosphorylation-related mutants were specifically hypersensitive to LiPF6. In these deletion mutants, LiPF6 treatment resulted in higher ROS production and reduced ATP levels, suggesting that oxidative phosphorylation-related genes were important for counteracting LiPF6-induced toxicity. Taken together, our results identified genes specifically involved in LiPF6-modulated toxicity, and demonstrated that oxidative stress and ATP imbalance maybe the driving factors in governing LiPF6-induced toxicity.

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