Residental Finance Tags

Residental Finance Tags > Tag based links for Cap

The following links have been tagged cap by users just like you, because these resources are off-site we cannot guarantee the accuracy or quality of any third-party information.

Cyclin-depende nt kinase 9 (Cdk9) of fission yeast is activated by the CDK-activating kinase Csk1, overlaps functionally with the TFIIH-associat ed kinase Mcs6, and associates with the mRNA cap methyltransfer ase Pcm1 in vivo.: Mol Cell Biol, Vol. 26, No. 3. (February 2006), pp. 777-788.Cyclin -dependent kinase 9 (Cdk9) of fission yeast is an essential ortholog of metazoan positive transcription elongation factor b (P-TEFb), which is proposed to coordinate capping and elongation of RNA polymerase II (Pol II) transcripts. Here we show that Cdk9 is activated to phosphorylate Pol II and the elongation factor Spt5 by Csk1, one of two fission yeast CDK-activating kinases (CAKs). Activation depends on Cdk9 T-loop residue Thr-212. The other CAK-Mcs6, the kinase component of transcription factor IIH (TFIIH)-cannot activate Cdk9. Consistent with the specificities of the two CAKs in vitro, the kinase activity of Cdk9 is reduced approximately 10-fold by csk1 deletion, and Cdk9 complexes from csk1Delta but not csk1+ cells can be activated by Csk1 in vitro. A cdk9(T212A) mutant is viable but phenocopies conditional growth defects of csk1Delta strains, indicating a role for Csk1-dependent activation of Cdk9 in vivo. A cdk9(T212A) mcs6(S165A) strain, in which neither Cdk9 nor Mcs6 can be activated by CAK, has a synthetic growth defect, implying functional overlap between the two CDKs, which have distinct but overlapping substrate specificities. Cdk9 forms complexes in vivo with the essential cyclin Pch1 and with Pcm1, the mRNA cap methyltransfer ase. The carboxyl-termi nal region of Cdk9, through which it interacts with another capping enzyme, the RNA triphosphatase Pct1, is essential. Together, the data support a proposed model whereby Cdk9/Pch1-the third essential CDK-cyclin complex described in fission yeast-helps to target the capping apparatus to the transcriptiona l elongation complex.

Source: Mol Cell Biol, Vol. 26, No. 3. (February 2006), pp. 777-788.
The spanish connection: transcription and mRNA processing get even closer.: Cell, Vol. 120, No. 2. (28 January 2005), pp. 163-166.The synthesis of mRNA by RNA polymerase II appears coupled to numerous RNA-processing events, based on physical or functional connections revealed by biochemical or genetic tests. New findings were presented at a recent meeting in Spain that begin to illuminate the mechanisms underlying the connections between mRNA processing and specific steps in transcription (initiation, elongation, and termination) as well as recombination.

Source: Cell, Vol. 120, No. 2. (28 January 2005), pp. 163-166.
Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study.: Thorax, Vol. 58, No. 5. (May 2003), pp. 377-382.BACKGR OUND: In the assessment of severity in community acquired pneumonia (CAP), the modified British Thoracic Society (mBTS) rule identifies patients with severe pneumonia but not patients who might be suitable for home management. A multicentre study was conducted to derive and validate a practical severity assessment model for stratifying adults hospitalised with CAP into different management groups. METHODS: Data from three prospective studies of CAP conducted in the UK, New Zealand, and the Netherlands were combined. A derivation cohort comprising 80% of the data was used to develop the model. Prognostic variables were identified using multiple logistic regression with 30 day mortality as the outcome measure. The final model was tested against the validation cohort. RESULTS: 1068 patients were studied (mean age 64 years, 51.5% male, 30 day mortality 9%). Age >/=65 years (OR 3.5, 95% CI 1.6 to 8.0) and albumin 7 mmol/l, Respiratory rate >/=30/min, low systolic(

Source: Thorax, Vol. 58, No. 5. (May 2003), pp. 377-382.
[Prediction rules in community acquired pneumonia]: Rev Med Chil, Vol. 132, No. 9. (September 2004), pp. 1027-1030.The determination of site of care is an essential decision in the management of patients with community-acqu ired pneumonia (CAP). Patients with mild to moderate CAP may be safely treated at home. Instead, those patients with severe pneumonia must be hospitalized to assure an effective treatment. Severity of CAP is associated with mortality that depends both on the patient's frailty and the intensity of lung inflammation. Because there is no single predictor factor to assess prognosis, diverse prediction rules have been developed to establish severity of CAP and guide the decision of site of care. In our country a new prediction rule, derived from hospitalized patents that incorporate simple clinical variables has been developed. However, this rule requires to be validated in the ambulatory setting before its wide spread use is suggested. Prediction rules are objective and relatively accurate models to assess prognosis that may aid clinicians to evaluate patient's risks and to improve hospitalizatio n decisions. Nevertheless, although the prediction rules may guide the initial management of patients with CAP, they are not intended to replace the clinical judgment, which remains as the "art of medicine."

Source: Rev Med Chil, Vol. 132, No. 9. (September 2004), pp. 1027-1030.
Integration of the CAD/CAPP/PPC systems: Journal of Materials Processing Technology, Vol. 164-165 (15 May 2005), pp. 1358-1368.The necessary condition that must be performed in order to ensure full functional integration of the computer aiding systems of technical and organizational production preparation is utilisation of the coherent product model. Utilisation of feature method for representation s of the construction and the technological process elements is a key factor for integration of design and technological process planning--CAD/ CAPP integration model. The availability of alternative process plans plays the main role in the CAPP/PPC system integration. The main advantage of the accessibility of alternative process plans for product is that we may fast react on a disturbance in the course of the manufacturing process by help of the reactions knowledgebase- -one of the module of proposed PPC system. This paper describes a methodology for integration CAD/CAPP/PPC systems in detail.

Source: Journal of Materials Processing Technology, Vol. 164-165 (15 May 2005), pp. 1358-1368.
Structure and dynamics of the modular halves of Escherichia coli cyclic AMP receptor protein.: Biochemistry, Vol. 41, No. 50. (17 December 2002), pp. 14771-14778.E. coli cyclic AMP receptor protein, CRP, is a modular protein that consists of a covalent linkage of two common structural domains. To probe the mechanism for intramolecular communications and to define the unique properties acquired by covalent linkage, the structural, and functional properties of the cAMP- and DNA-binding domains of CRP were studied separately as two independent polypeptides. The N-terminal cAMP-binding domain (alpha-CRP), including S-CRP and CH-CRP, which were generated by digestion of CRP by subtilisin and chymotrypsin, respectively, are mainly populated by beta-sheets. The C-terminal DNA-binding domain, designated as beta-CRP, consists of mostly alpha-helices. The residues of S-CRP and CH-CRP are from 1 to 116 and 1 to 136 of intact wild-type CRP, and those of beta-CRP are from 108 to 209. The secondary structures of alpha-CRP and beta-CRP were monitored by FT-IR, and they are similar to those of the corresponding parts in intact wild-type CRP. Results from hydrogen-deute rium exchange experiments indicated that beta-CRP is more dynamic than alpha-CRP. In an earlier study, it was shown that alpha-CRP retains the function of binding cAMP [Heyduk, E., et al. (1992) Biochemistry 31, 3682-3688]. beta-CRP was able to bind to DNA, although only weakly, and was not sequence specific. Thus, a covalent linkage between the two domains is essential for the realization of the intramolecular signal transmission between the domains triggered by ligand binding. The acquisition of this unique property is intimately associated with the dynamics of the molecule.

Source: Biochemistry, Vol. 41, No. 50. (17 December 2002), pp. 14771-14778.
Structural Understanding of the Allosteric Conformational Change of Cyclic AMP Receptor Protein by Cyclic AMP Binding: Biochemistry, Vol. 39, No. 45. (14 November 2000), pp. 13953-13962.Ab stract: Cyclic AMP receptor protein (CRP) plays a key role in the regulation of more than 150 genes. CRP is allosterically activated by cyclic AMP and binds to specific DNA sites. A structural understanding of this allosteric conformational change, which is essential for its function, is still lacking because the structure of apo-CRP has not been solved. Therefore, we performed various NMR experiments to obtain apo-CRP structural data. The secondary structure of apo-CRP was determined by analyses of the NOE connectivities , the amide proton exchange rates, and the 1H-15N steady-state NOE values. A combination of the CSI-method and TALOS prediction was also used to supplement the determination of the secondary structure of apo-CRP. This secondary structure of apo-CRP was compared with the known structure of cyclic AMP-bound CRP. The results suggest that the allosteric conformational change of CRP caused by cyclic AMP binding involves subunit realignment and domain rearrangement, resulting in the exposure of helix F onto the surface of the protein. Additionally, the results of the one-dimensiona l [13C]carbonyl NMR experiments show that the conformational change of CRP caused by the binding of cyclic GMP, an analogue of cyclic AMP, is different from that caused by cyclic AMP binding.

Source: Biochemistry, Vol. 39, No. 45. (14 November 2000), pp. 13953-13962.
Catabolite Activator Protein in Aqueous Solution: A Molecular Simulation Study: J. Phys. Chem. B, Vol. 111, No. 6. (15 February 2007), pp. 1496-1501.Abst ract: The homodimeric catabolite activator protein (CAP) is a bacterial DNA binding transcription regulator whose activity is controlled by the binding of the intracellular mediator cyclic adenosine monophosphate (cAMP). Each CAP subunit consists of a cyclic nucleotide and a DNA binding domain. Here, we investigate the structural features of the ligand-bound CAP in aqueous solution by molecular dynamics simulations based on the available X-ray structures (Passner et al. J. Mol. Biol. 2000, 304, 847-859 and Chen et al. J. Mol. Biol. 2001, 314, 63-74). Our calculations suggest that the homodimer in solution assumes a symmetric arrangement in which both DNA binding domains are separated from the respective cyclic nucleotide binding domains by a cleft. This contrasts with the X-ray structure, which exhibits instead an asymmetric conformation. On the basis of electrostatics calculations, we propose that the symmetric structure in solution may be an important feature for DNA molecular recognition.

Source: J. Phys. Chem. B, Vol. 111, No. 6. (15 February 2007), pp. 1496-1501.
Energetics of intersubunit and intrasubunit interactions of Escherichia coli adenosine cyclic 3',5'-phosphat e receptor protein.: Biochemistry, Vol. 32, No. 32. (17 August 1993), pp. 8130-8139.Esch erichia coli cAMP receptor protein (CRP) regulates the expression of a large number of catabolite-sen sitive genes. The mechanism of CRP regulation most likely involves communication between subunits and domains. A specific message, such as the activation of CRP, may be manifested as a change in the interactions between these structural entities. Hence, the elucidation of the regulatory mechanism would require a quantitative evaluation of the energetics involved in these interactions. Thus, a study was initiated to define the conditions for reversible denaturation of CRP and to quantitatively assess the energetics involved in the intra- and intersubunit interactions in CRP. The denaturation of CRP was induced by guanidine hydrochloride. The equilibrium unfolding reaction of CRP was monitored by three spectroscopic techniques, namely, fluorescence intensity, fluorescence anisotropy, and circular dichroism. The spectroscopic data implied that CRP unfolds in a single cooperative transition. Sedimentation equilibrium data showed that CRP is dissociated into its monomeric state in high concentrations of denaturant. Unfolding of CRP is completely reversible, as indicated by fluorescence and circular dichroism measurements, and sedimentation data indicated that a dimeric structure of CRP was recovered. The functional and other structural properties of renatured and native CRP have also been examined. Quantitatively identical results were obtained. Results from additional studies as a function of protein concentration and from computer simulation demonstrated that the denaturation of CRP induced by guanidine hydrochloride proceeds according to the following pathway: (CRP2)Native2( CRP)Native2(CR P)Denatured. The delta G values for dissociation (delta Gd) and unfolding (delta G(u)) in the absence of guanidine hydrochloride were determined by linear extrapolation, yielding values of 12.0 +/- 0.6 and 7.2 +/- 0.1 kcal/mol, respectively. To examine the effect of the DNA binding domain on the stability of the cAMP binding domain, two proteolyticall y resistant cAMP binding cores were prepared from CRP in the presence of cAMP by subtilisin and chymotrypsin digestion, yielding S-CRP and CH-CRP, respectively. Results from an equilibrium denaturation study indicated that the denaturation of both CH-CRP and S-CRP is also completely reversible. Both S-CRP and CH-CRP exist as stable dimers with similar delta Gd values of 10.1 +/- 0.4 and 9.5 +/- 0.4 kcal/mol, respectively. Results from this study in conjunction with crystallograph ic data [McKay, D. B., Weber, I. T., & Stietz, T. A. (1982) J. Biol. Chem. 257, 9518-9524] indicate that the DNA binding domain and the C-helix are not the only structural elements that are responsible for subunit dimerization.( ABSTRACT TRUNCATED AT 400 WORDS)

Source: Biochemistry, Vol. 32, No. 32. (17 August 1993), pp. 8130-8139.
Kinetic and Structural Studies of the Allosteric Conformational Changes Induced by Binding of cAMP to the cAMP Receptor Protein from Escherichia coli: Biochemistry, Vol. 45, No. 2. (17 January 2006), pp. 373-380.Abstra ct: The cAMP receptor protein, allostericaly activated by cAMP, regulates the expression of more than 100 genes in Escherichia coli. CRP is a homodimer of two-domain subunits. It has been suggested that binding of cAMP to CRP leads to a long-distance signal transduction from the N-terminal cAMP binding domain to the C-terminal domain of the protein responsible for interaction with specific sequences of DNA. In this study, the stopped-flow and time-resolved fluorescence lifetime measurements were used to observe the kinetics of the distance changes between the N-terminal and C-terminal domain of CRP induced by binding of cAMP to high-affinity binding sites. In these measurements, we used the constructed CRP heterodimer, which possesses a single Trp85 residue localized at the N-terminal domain of one CRP subunit, and fluorescently labeled by 1,5-I-AEDANS Cys178 localized at the C-terminal domain of the same subunit or at the opposite one. The Förster resonance energy transfer method has been used to study the distance changes, induced by binding of cAMP, between Trp85 (fluorescence donor) and Cys178-AEDANS (fluorescence acceptor) in the CRP structure. The obtained results show that the allosteric transitions of CRP at micromolar cAMP concentrations follow the sequential binding model, in which binding of cAMP to high-affinity sites causes a 4 Ĺ movement of the C-terminal domain toward N-terminal domains of the protein, with kinetics faster than 2 ms, and CRP adopts the "closed" conformation. This fast process is followed by the slower reorientation of both CRP subunits.

Source: Biochemistry, Vol. 45, No. 2. (17 January 2006), pp. 373-380.

If you would like to find additional social bookmark based links on the topic of cap we recommend the Open Tag Directory > Cap. If you would like to find related tags we recommend Tag Patterns > Cap.