This Research Topic addresses the metabolism and function of the amino acid Serine in plants. We emphasize the interaction and coordination between the Serine biosynthetic pathways and other metabolic pathways.Serine is a polar amino acid that plays a fundamental role in plant metabolism, plant development, and cell signalling. In addition to being a building block for proteins, Serine participates in the biosynthesis of biomolecules such as amino acids, nucleotides, phospholipids, and sphingolipids. Plants possess at least two serine biosynthetic pathways: i) the glycolate pathway associated with photorespiration and ii) the so-called Phosphorylated Pathway of Serine Biosynthesis. The biological significance of the coexistence of several pathways for the biosynthesis of Serine is not known. In particular, we poorly understand the contribution that each pathway makes to plant serine homeostasis, how pathways are integrated and coordinated, and how they interact at the transcriptional/translational
TY - JOUR. T1 - An Akt3 splice variant lacking the serine 472 phosphorylation site promotes apoptosis and suppresses mammary tumorigenesis. AU - Suyama, Kimita. AU - Yao, Jiahong. AU - Liang, Huizhi. AU - Benard, Outhiriaradjou. AU - Loudig, Olivier D.. AU - Amgalan, Dulguun. AU - McKimpson, Wendy M.. AU - Phillips, Greg R.. AU - Segall, Jeffrey E.. AU - Wang, Yihong. AU - Fineberg, Susan A.. AU - Norton, Larry. AU - Kitsis, Richard N.. AU - Hazan, Rachel. PY - 2018/1/1. Y1 - 2018/1/1. N2 - The Akt pathway is a well-known promoter of tumormalignancy. Akt3 is expressed as two alternatively spliced variants, one of which lacks the key regulatory serine 472 phosphorylation site. Whereas the function of full-length Akt3 isoform (Akt3/+S472) is well-characterized, that of Akt3/S472 isoformremains unknown. Despite being expressed at a substantially lower level than Akt3/ +S472 in triple-negative breast cancer cells, specific ablation of Akt3/S472 enhanced, whereas overexpression, suppressed mammary ...
The IKK complex, isolated from extracts of HeLa cells treated with the proinflammatory cytokine TNF (tumor necrosis factor), phosphorylates two regulatory serine residues at the NH2-termini of the NF-κB inhibitors IκBα and IκBβ (1). This phosphorylation event triggers the polyubiquitination of IκBs followed by their degradation through the 26S proteasome, and thereby leads to NF-κB activation (2). IKK is a large, 900-kD, protein complex that is composed of multiple subunits. Two of these subunits, IKKα and IKKβ, are serine kinases (1, 3-6). Epitope-tagged IKKα and IKKβ, when produced by cell-free translation in reticulocyte lysates or by transient transfection of mammalian cells, are incorporated into the IKK complex, which can be isolated by immunoprecipitation of either IKKα or IKKβ (1, 4). The IκB kinase activity of the entire complex is rapidly stimulated by TNF or interleukin 1 (IL-1), with kinetics matching those of IκBα phosphorylation and degradation (1,4).. Because ...
Serine definition, definition of serine, Anagrams of serine, words that start with Serine, and words that can be created from serine
BioAssay record AID 493218 submitted by NCGC: Immunofluorescence assay for KAP-1 phosphorylation on Ser824 for Identifying a Potential Treatment of Ataxia-Telangiectasia: Hit Validation.
There might be another problem with the scoring function, along the same lines as the issue with design puzzles favoring the large aromatic side chains.. From what Ive read, serine is considered a structure-breaking amino acids and does not normally show up in sheets or helices. So, if serine doesnt belong in a beta sheet in nature, I wouldnt expect the mutate function to be substituting it into beta sheets very often. However, Ive noticed that in freestyle design Im often getting serine in my beta sheets. If it were just one or two, that would be realistic, but Im looking at a ten-segment beta strand with four serines, and in one case recently I had a sheet that was almost entirely serines. That cant be right.. ...
Reactome is pathway database which provides intuitive bioinformatics tools for the visualisation, interpretation and analysis of pathway knowledge.
Press Release issued Jul 19, 2017: The purpose of Global Serine Market report is to provide the newest industry data and Serine industry future trends, allowing consumers to identify the Serine market Application, Type, Manufacturers and Regions, Serine market Forecast up to 2022.
The observations that UCN-01 blocked the stabilization and phosphorylation of p53 on serine 20, whereas serine 15 remained phosphorylated, are in agreement with a previous report showing that phosphorylation on serine 20 rather than serine 15 contributes to p53 stabilization (20) , which suggests that UCN-01 blocks IR-induced p53 stabilization, most likely by inhibiting Chk2 kinase. Consistent with this notion, we found that UCN-01 effectively inhibited the immunoprecipitated kinase activity of endogenous Chk2 from HCT116 cells (IC50, ∼10 nm; Fig. 2B ⇓ ). UCN-01 has been shown previously to inhibit recombinant Chk1 rather than recombinant Chk2 kinases as determined by in vitro biochemical assays (24 , 25) . It is not likely that the inhibition of immunoprecipitated Chk2 is caused by the unspecific immunoprecipitation because Chk2 antibody obtained from another source gave a similar result. 3 Furthermore, this kinase would have to be active on GST-Cdc25C and to be sensitive to UCN-01. The ...
Paleologou, K. E.; Oueslati, A.; Shakked, G.; Rospigliosi, C. C.; Kim, H. Y.; Lamberto, G. R.; Fernandez, C. O.; Schmid, A.; Chegini, F.; Gai, W. P. et al.; Chiappe, D.; Moniatte, M.; Schneider, B. L.; Aebischer, P.; Eliezer, D.; Zweckstetter, M.; Masliah, E.; Lashuel, H. A.: Phosphorylation at S87 is enhanced in synucleinopathies, inhibits α-synuclein oligomerization and influences synuclein-membrane interactions. Journal of Neuroscience 30 (9), pp. 3184 - 3198 (2010 ...
Phosphatidyl L Serine is an important chemical with widespread functions in the body It is part of the cell structure and is key in the maintenance of cellular function, especially in the brain
Immunohistochemical (IHC) staining for pS6 (serine 235/236 and serine 240/244) and PTEN was performed just before and during the everolimus re-treatment. All ph
A scientific resource for the WD40 protein domain containing information on structure, function, and binding to both phospho-Ser/Thr and methylated lysine residues.
Function: May be a SFC-associated serine kinase (splicing factor compartment-associated serine kinase) with a role in intranuclear SR protein (non-snRNP splicing factors containing a serine/arginine-rich domain) trafficking and pre-mRNA processing ...
5 Phosphorylation is needed if an oligo is used as a substrate for DNA ligase. 3 Phosphorylation will inhibit degradation by some 3-exonucleases and can be used to block extension by DNA polymerases.. View product details for Phosphorylation:. ...
MVMADGPRHLQRGPVRVGFYDIEGTLGKGNFAVVKLGRHRITKTEVAIKIIDKSQLDAVNLEKIYREVQI 1 - 70 MKMLDHPHIIKLYQVMETKSMLYLVTEYAKNGEIFDYLANHGRLNESEARRKFWQILSAVDYCHGRKIVH 71 - 140 RDLKAENLLLDNNMNIKIADFGFGNFFKSGELLATWCGSPPYAAPEVFEGQQYEGPQLDIWSMGVVLYVL 141 - 210 VCGALPFDGPTLPILRQRVLEGRFRIPYFMSEDCEHLIRRMLVLDPSKRLTIAQIKEHKWMLIEVPVQRP 211 - 280 VLYPQEQENEPSIGEFNEQVLRLMHSLGIDQQKTIESLQNKSYNHFAAIYFLLVERLKSHRSSFPVEQRL 281 - 350 DGRQRRPSTIAEQTVAKAQTVGLPVTMHSPNMRLLRSALLPQASNVEAFSFPASGCQAEAAFMEEECVDT 351 - 420 PKVNGCLLDPVPPVLVRKGCQSLPSNMMETSIDEGLETEGEAEEDPAHAFEAFQSTRSGQRRHTLSEVTN 421 - 490 QLVVMPGAGKIFSMNDSPSLDSVDSEYDMGSVQRDLNFLEDNPSLKDIMLANQPSPRMTSPFISLRPTNP 491 - 560 AMQALSSQKREVHNRSPVSFREGRRASDTSLTQGIVAFRQHLQNLARTKGILELNKVQLLYEQIGPEADP 561 - 630 NLAPAAPQLQDLASSCPQEEVSQQQESVSTLPASVHPQLSPRQSLETQYLQHRLQKPSLLSKAQNTCQLY 631 - 700 CKEPPRSLEQQLQEHRLQQKRLFLQKQSQLQAYFNQMQIAESSYPQPSQQLPLPRQETPPPSQQAPPFSL 701 - 770 TQPLSPVLEPSSEQMQYSPFLSQYQEMQLQPLPSTSGPRAAPPLPTQLQQQQPPPPPPPPPPRQPGAAPA 771 - 840 ...
As discussed earlier, cells can acquire serine by either synthesizing it internally or importing serine from the environment. Serine is a small, neutral amino acid and, as such, can be transported by one of three systems. Two of the systems are sodium dependent: the alanine/serine/cysteine/threonine transporters ASCT1 and ASCT2 (encoded by SLC1A4 and SLC1A5, respectively) and the system A transporters SAT1 and SAT2 (encoded by SLC38A1 and SLC38A2, respectively). The third is a family of neutral amino acid antiporters, the alanine/serine/cysteine transporter (ASC) system (El-Hattab, 2016). These antiporters are of particular interest because they are active even at steady state, so that for instance, one molecule of intracellular serine can be exchanged for one molecule of extracellular serine. Normally this process goes unnoticed, but a recent study (DeNicola et al., 2015) points out that it can complicate interpretation of heavy isotope-labeling experiments by setting up an exchange flux ...
Visconti R., Gadina M., Chiariello M., Chen E.H., Stancato L.F., Gutkind J.S., OShea J.J.. Interleukin-12 (IL-12) is a key immunoregulatory cytokine that promotes Th1 differentiation and cell-mediated immune responses. The transcription factor STAT4 (signal transducer and activator of transcription 4) is an important element in mediating IL-12 signals, as evidenced by the fact that STAT4(-/-) mice display impaired responsiveness to IL-12 and deficient Th1 differentiation. STAT4 is inducibly phosphorylated on tyrosine and serine in response to IL-12, but the kinase(s) responsible for the latter event is unknown. Here we show that IL-12 induces STAT4 phosphorylation on serine 721 and that mutation of serine 721 interferes with STAT4 transcriptional activity. In addition, we show that mutation of tyrosine 693 abrogates IL-12-induced STAT4 tyrosine phosphorylation and transcriptional activity. Although the site surrounding serine 721 is an optimum consensus sequence for mitogen-activated family of ...
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PKA phosphorylation increases the tyrosine kinase activity of Csk towards an endogenous substrate. Tyrosine phosphorylation of heat-inactivated (65°C for 10 mi
Combining with a signal and transmitting the signal from one side of the membrane to the other to initiate a change in cell activity by catalysis of the reaction: ATP protein serine = ADP + protein serine phosphate, and ATP + protein threonine = ADP + pro…
The structure of the Mg(2+)-dependent enzyme human phosphoserine phosphatase (HPSP) was exploited to examine the structural and functional role of the divalent cation in the active site of phosphatases. Most interesting is the biochemical observation that a Ca(2+) ion inhibits the activity of HPSP, even in the presence of added Mg(2+). The sixfold coordinated Mg(2+) ion present in the active site of HPSP under normal physiological conditions, was replaced by a Ca(2+) ion by using a crystallization condition with high concentration of CaCl(2) (0.7 m). The resulting HPSP structure now shows a sevenfold coordinated Ca(2+) ion in the active site that might explain the inhibitory effect of Ca(2+) on the enzyme. Indeed, the Ca(2+) ion in the active site captures both side-chain oxygen atoms of the catalytic Asp20 as a ligand, while a Mg(2+) ion ligates only one oxygen atom of this Asp residue. The bidentate character of Asp20 towards Ca(2+) hampers the nucleophilic attack of one of the Asp20 side ...
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Clone REA134 recognizes AKT1, which is also known as protein kinase Bα. AKT1 is a serine/threonine protein kinase, belonging to the AKT family of kinases and like each AKT family member, contains an N-terminal pleckstrin homology (PH) domain, a central kinase domain, and a carboxyl-terminal regulatory domain with a hydrophobic motif (HM). Activation of AKT1 is achieved via phosphorylation at multiple sites, which take place in response to engagement of receptors such as platelet derived growth factor receptor (PDGF-R). Activated AKT1 further phosphorylates and alters the activity of several downstream substrates allowing AKT1 to play a vital role in various biological processes such as cell growth, survival, migration, and proliferation. Additional information: Clone REA134 displays negligible binding to Fc receptors. - Belgique
Detail záznamu - Inhibition of Human Serine Racemase, an Emerging Target for Medicinal Chemistry - Detail záznamu - Knihovna Akademie věd České republiky
Concepts regarding the controls and consequences of PKD1-Ser738/Ser742 (activation loop) phosphorylation are based largely on early studies that used an anti-PKD1-Ser(P)738/Ser(P)742 PSSA (from Cell Signaling Technology, Danvers, MA) and showed that PMA increases PKD1 activation loop phosphorylation in many cell types via a mechanism that requires nPKC isoform activity (PKCδ, PKCε, PKCη, and/or PKCθ). In vitro kinase assays showing direct phosphorylation of the PKD1 activation loop by certain nPKC isoforms also have been published (Brändlin et al., 2002). However, there is recent evidence that the Cell Signaling Technology anti-PKD1-Ser(P)738/Ser(P)742 PSSA primarily recognizes PKD1 phosphorylation at Ser738 and that PKD1 phosphorylation at Ser742 can be tracked with a different PSSA (commercially available from Abcam Inc., Cambridge, MA). Experiments that use a combined approach with these two PSSAs expose differences in the controls and consequences of PKD1 phosphorylation at Ser738 and ...
A large body of work has implicated the activity of various kinases and phosphatases in the regulation of synaptic transmission by controlling the phosphorylation state of several synaptic proteins (for review, see Turner et al., 1999). To further understand the physiological significance of these modifications and to gain insights into their role in modulating synaptic strength and plasticity, we have generated a set of antibodies that specifically recognize synaptic proteins only in their phosphorylated form. In this study we report the biochemical characterization of the modulation of phosphorylation of rabphilin, a synaptic protein implicated in exocytosis, using phosphospecific antibodies directed against the two major phosphorylation sites of rabphilin, serine-234 and serine-274.. Our results show that the phosphorylation of rabphilin at serine-234 is greatly stimulated (about sevenfold over basal) by activation of PKA and high K+-induced membrane depolarization, a condition that mimics ...
Interestingly, recent in vitro kinetic studies using recombinant active p38α expressed in Escherichia coli showed that p38 phosphorylates GST-ATF2 (amino acids 1-115) via a two‐step (double collision) mechanism, involving the dissociation of mono‐phosphorylated ATF2 Thr71 or Thr69 from the enzyme after the first phosphorylation step (Waas et al., 2001). Moreover, these authors found that mono‐phosphorylation of ATF2 Thr69 strongly reduces the phosphorylation rate of Thr71, whereas, in contrast, mono‐phosphorylation of Thr71 does not reduce the rate of Thr69 phosphorylation. Thus, efficient phosphorylation of ATF2 by recombinant E.coli‐expressed active p38 only occurs in the order Thr71→ Thr69 + 71 (Figure 7). This order of events also seems to occur in mitogen‐treated cells, as ERK, in contrast to p38, does not seem to mono‐phosphorylate Thr69 significantly (Figure 4C).. The fact that ERK does not double‐phosphorylate ATF2 Thr69 + 71 efficiently raises the question as to ...
以下に掲載:Cancer Science 105 pp.1307-1312 2014. Japanese Cancer Association 共著者:Eiichi Kato, Makoto Orisaka, Tetsuji Kurokaw
Goat Polyclonal Anti-Phosphoserine phosphatase Antibody. Validated: WB, PEP-ELISA. Tested Reactivity: Human, Mouse. 100% Guaranteed.
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reacts with Akt when phosphorylated at Ser473; also reacts with Akt2 and Akt3 when phosphorylated at corresponding residues. Does not recognize Akt phosphorylated at other sites, nor does it recognize phosphorylated forms of related kinases such as PKC or p70 S6 ...
Serine exists as a zwitterion. In very acidic solutions (pH 1), the COO⁻ group will be protonated The pK_a values are: COOH = 2.2 NH₃⁺ = 9.2 As you make the solution more basic, you will remove the acidic protons one by one. By the time you reach pH 12, you will have removed all of the acidic protons. Serine will exist as NH₂CH(CH₂OH)COO⁻.
Serine Ser, S A non-essential amino acid occurring in natural form as the L-isomer. It is synthesized from GLYCINE or THREONINE. It is involved in the biosynthesis of PURINES; PYRIMIDINES; and other amino acids. Name L-Serine MeSH 68012694 CAS No.56-45-1Molecular Formula
Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-299; THR-301; SER-394; SER-397; SER-402; THR-404; THR-449; SER-453; THR-455; SER-495; SER-498; SER-513; SER-780; SER-793; SER-1033; SER-1068; THR-1198; SER-1399; SER-1400; THR-1403; THR-1425; THR-1466; THR-1548; THR-1589; SER-1604; THR-1630; THR-1664; THR-1671; SER-1681; THR-1697; SER-1702; SER-1711; SER-1775 AND THR-1858; VARIANT [LARGE SCALE ANALYSIS] PRO-1540; IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS]; ...
Furthermore, considering that at the N-terminus, the K13 SUMO/ acetylation site is adjacent to the S10 O-GlcNAcylation/phosphorylation website we will further
201 Page 210 202 D. 3 KID domain from CREB, phosphorylated on Ser133 Snovitra xl 60 mg in a complex with the KIX domain of CBP. AlвBadr were applied successfully for the determination of miconazole and the other anti- fungal drug in their pharmaceutical formulation. The snovitra and ventricular electrograms are on top and the s novitra markers at snovtira bottom.
Could the Glycine/Serine ratio could tell us anything about whether a person is over/undermethlyated? I dont think it could be used all by itself, but...
MSDSLWTALSNFSMPSFPGGSMFRRTKSCRTSNRKSLILTSTSPTLPRPHSPLPGHLGSSPLDSPRNFSP 1 - 70 NTPAHFSFASSRRADGRRWSLASLPSSGYGTNTPSSTVSSSCSSQERLHQLPYQPTVDELHFLSKHFGST 71 - 140 ESITDEDGGRRSPAVRPRSRSLSPGRSPSSYDNEIVMMNHVYKERFPKATAQMEEKLRDFTRAYEPDSVL 141 - 210 PLADGVLSFIHHQIIELARDCLTKSRDGLITTVYFYELQENLEKLLQDAYERSESLEVAFVTQLVKKLLI 211 - 280 IISRPARLLECLEFNPEEFYHLLEAAEGHAKEGHLVKTDIPRYIIRQLGLTRDPFPDVVHLEEQDSGGSN 281 - 350 TPEQDDLSEGRSSKAKKPPGENDFDTIKLISNGAYGAVYLVRHRDTRQRFAMKKINKQNLILRNQIQQAF 351 - 420 VERDILTFAENPFVVGMFCSFETRRHLCMVMEYVEGGDCATLLKNIGALPVEMARMYFAETVLALEYLHN 421 - 490 YGIVHRDLKPDNLLITSMGHIKLTDFGLSKMGLMSLTTNLYEGHIEKDAREFLDKQVCGTPEYIAPEVIL 491 - 560 RQGYGKPVDWWAMGIILYEFLVGCVPFFGDTPEELFGQVISDDILWPEGDEALPTEAQLLISSLLQTNPL 561 - 630 VRLGAGGAFEVKQHSFFRDLDWTGLLRQKAEFIPHLESEDDTSYFDTRSDRYHHVNSYDEDDTTEEEPVE 631 - 700 IRQFSSCSPRFSKVYSSMEQLSQHEPKTPVAAAGSSKREPSTKGPEEKVAGKREGLGGLTLREKTWRGGS 701 - 770 PEIKRFSASEASFLEGEASPPLGARRRFSALLEPSRFSAPQEDEDEARLRRPPRPSSDPAGSLDARAPKE 771 - 840 ...
Mediator of cell growth. Modulates apoptosis. In association with STK24 negatively regulates Golgi reorientation in polarized cell migration upon RHO activation.
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Members LATS1 LATS2 WKP Serine/threonine-protein kinase LATS1 is an enzyme that in humans is encoded by the LATS1 gene. It has been (...)
Looking for online definition of Serine racemase in the Medical Dictionary? Serine racemase explanation free. What is Serine racemase? Meaning of Serine racemase medical term. What does Serine racemase mean?
Regulation of type I IFN signaling through STAT2 has remained understudied chiefly because the diversity of STAT TADs and the sequence divergence of the STAT2 TAD among different species have made it challenging to predict amino acids in STAT2 that might be important for proper transcriptional activity (Park et al., 1999; Paulson et al., 1999). For example, serine phosphorylation within the P(M)SP motifs found in several STAT transactivation domains has been shown to be required for STAT-dependent gene regulation. In contrast, STAT2 lacks this conserved motif, and this opens the door to investigate the biological role of serine-phosphorylated STAT2.. Our study provides new evidence that serine phosphorylation of STAT2 plays a pivotal role in selectively regulating the biological actions of type I IFNs. We have identified a serine phosphorylation site (S734) on STAT2 that resides in the TAD, but that is away from the crucial region previously mapped for transactivation. This new site appears to ...
In the present study, we investigate the mechanism for the protein kinase A (PKA)-mediated activation of C-terminal Src kinase (Csk). Although isolated Csk kinase domain was phosphorylated at Ser364 by PKA to the same stoichiometry as wild-type Csk, significant activation of the isolated Csk kinase domain by PKA was observed only in the presence of the purified Src homology 3 domain (SH3 domain). Furthermore, the interaction between the SH3 and kinase domains was facilitated by PKA-mediated phosphorylation of the kinase domain, as evaluated by surface plasmon resonance. This suggests that an overall structural domain organization and interaction between the kinase and SH3 domains are important for the activity of Csk and its regulation by PKA.. ...
Aromatase inhibitors (AIs) are effective endocrine therapeutics for postmenopausal women with estrogen receptor (ER)α‑positive breast cancer. However, the efficacy of the treatment is often limited by the onset of AI resistance, owing to the phosphorylation of ERα serine 167 (Ser167). Previous studies have indicated that hyperactivation of the phosphoinositide‑3 kinase/RAC serine/threonine‑protein kinase signaling pathway occurs in AI‑resistant breast cancer models, which coincides with elevated levels of ERα phosphorylation at Ser167. The tumor suppressor serine/threonine‑protein phosphatase 2A (PP2A) regulates the phosphatidylinositol 3‑kinase/RAC serine/threonine‑protein kinase signaling pathway. A previous study indicated that PP2A inhibition decreased ERα Ser167 phosphorylation and estradiol (E2)‑independent cell growth. The present study investigated the potential relevance of PP2A in E2 deprivation‑resistant MCF‑7 cells. E2 depletion reduced the susceptibility of ...
Agonist-induced phosphorylation has been demonstrated for a variety of GPCRs including the β-adrenergic (Ferguson et al., 1995; Freedman et al., 1995; Fredericks et al., 1996; January et al., 1997), α-adrenergic (Easonet al., 1995), δ-opioid (Pei et al., 1995), endothelin (Freedman et al., 1997), adenosine (Palmeret al., 1995), vasopressin (Innamorati et al., 1997), and somatostatin (Hipkin et al., 1997) receptors. However, there have been relatively few unequivocal reports of AT1-R phosphorylation. This has been due in large part to the inability to distinguish the immunoprecipitated phospho-AT1-R from more abundant phosphoproteins that either genuinely or spuriously coprecipitate with the receptor (Smith et al., 1998). Despite these problems, unequivocal agonist-induced phosphorylation of a transiently expressed epitope-tagged AT1-R (Oppermann et al., 1996), and of a stably expressed (His)6-tagged AT1-R (Balmforth et al., 1997) has been reported in human embryonic kidney 293 cells. We ...
BA-Stk1 is a serine/threonine kinase (STK) expressed by Bacillus anthracis. In previous studies, we found that BA-Stk1 activity is modulated through dephosphorylation by a partner phosphatase, BA-Stp1. In this study, we identified critical phosphorylation regions of BA-Stk1 and determined the contributions of these phosphodomains to autophosphorylation and substrate phosphorylation. The data indicate that BA-Stk1 undergoes trans-autophosphorylation within a regulatory domain, referred to as the activation loop, which carries eight putative regulatory serine and threonine residues. We identified activation loop mutants that impacted kinase activity in three different manners: regulation of autophosphorylation (T162), regulation of substrate phosphorylation (T159 and S169), and regulation of overall kinase activity (T163). Tandem mass spectrometry (MS/MS) analysis of the phosphorylation profile of each mutant revealed a second site of phosphorylation on the kinase that was influenced by the
It has been observed that coincident with or immediately following IκBα degradation, p65 is phosphorylated at multiple residues, and these phosphorylation events are necessary for proper regulation of NF-κB function (45). The phosphorylation patterns of NF-κB proteins have not been characterized in T cell anergy, and so we asked whether aberrant phosphorylation was responsible for the defects in NF-κB function in anergic cells. An early step involves phosphorylation of p65 at Ser536 by the IKK complex (32-35), and it has been suggested that phosphorylation at this residue negatively regulates the kinetics of p65 nuclear translocation (33). We found that p65 is phosphorylated at Ser536 equivalently in both naive and anergic cells, which is consistent with our finding that p65 translocates to the nucleus with normal kinetics in anergic T cells. A second posttranslational modification important for NF-κB activity is phosphorylation at Ser276. We found that, as with Ser536 phosphorylation, p65 ...