Protein kinases

Bài viết trình bày mục tiêu: Trimethyltin (TMT) đã được chứng minh gây ức chế biểu hiện của yếu tố dinh dưỡng thần kinh nguồn gốc từ não (Brain-derived neuophic factor-BDNF) trên mô hình chuột nhắt trắng. Nghiên cứu này được thực hiện nhằm đánh giá sự thay đổi hàm lượng BDNF, biểu hiện của Tropomyosin receptor kinase B (TrkB), BDNF và mRNA BDNF trong vùng hồi hải mã thuộc não chuột được tiêm TMT.

6p viharuno 11-01-2025 2 1   Download

Clenbuterol là một chất thuộc nhóm Beta agonist có tác dụng giãn phế quản, giãn cơ trơn ở cuống phổi (được sử dụng để điều trị bệnh về phổi), điều khiển các chất dinh dưỡng hướng tới mô cơ, tăng sinh quá trình tổng hợp protein để tích lũy nạc và giảm tích lũy mỡ trong cơ thể. Trong mạch máu: Clenbuterol kết hợp với Gs-protein làm tăng hoạt động cAMP, cAMP làm hoạt động cAMP-dependent protein kinase (PK-A) dẫn đến lượng Ca++ đi vào tế bào tăng lên ảnh hưởng đến màng cơ tim, làm tăng nhịp tim...

29p quocnamdhnl 08-12-2010 300 113   Download

Shikimate kinase was chosen as a convenient representative example of the subclass of a/b proteins with which to examine the mechanism of protein folding. In this paper we report on the refolding of the enzyme after denaturation in urea. As shown by the changes in secondary and tertiary structure monitored by far UV circular dichroism (CD) and fluorescence, respectively, the enzyme was fully unfolded in 4 M urea. From an analysis of the unfolding curve in terms of the two-state model, the stability of the folded state could be estimated as 17 kJÆmol)1.

9p system191 01-06-2013 49 5   Download

Certain amino acids, like glutamine and leucine, induce an anabolic response in liver. They activate p70 ribosomal protein S6 kinase (p70S6K) and acetyl-CoA carboxylase (ACC) involved in protein and fatty acids synthesis, respectively. In contrast, the AMP-activated protein kinase (AMPK), which senses the energy state of the cell and becomes activated under metabolic stress, inactivates by phosphorylation key enzymes in biosynthetic pathways thereby conserving ATP.

9p system191 01-06-2013 50 5   Download

Liver metabolism is influenced by hormones and nutrients. Amino acids such as glutamine or leucine induce an anabolic response, which resembles that of insulin in muscle and adipose tissue. In this work, the signalling pathways and the effects of insulin were compared to those of glutamine and leucine in isolated hepatocytes from normal and streptozotocin-diabetic rats.

9p system191 01-06-2013 50 5   Download

The plastid transcription kinase (PTK), a component of the major RNA polymerase complex from mustard chloroplasts, has been implicated in redox-mediated regulation of plastid gene expression. A cloning strategy to define the PTK gene(s) resulted in the isolation of a full-length cDNA for a protein with overall high homology with the a subunit of cytosolic casein kinase (CK2) that contained an N-terminal extension for a putative plastid transit peptide.

9p system191 01-06-2013 46 4   Download

An immuno-homologue of maize Ca2+/calmodulin (CaM)dependent protein kinase with a molecular mass of 72 kDa was identified in pea. The pea kinase (PsCCaMK) was upregulated in roots in response to low temperature and increased salinity. Exogenous Ca2+ application increased the kinase level and the response was faster than that obtained following stress application. Low temperaturemediated, but not salinity-mediated stress kinase increase was inhibited by the application of EGTA and W7, a CaM inhibitor....

12p system191 01-06-2013 39 5   Download

This study reports the identification and characterization of the regulatory subunit, TbRSU, of protein kinase A of the parasitic protozoon Trypanosoma brucei. TbRSU is coded for by a single copy gene. The protein contains an unusually long N-terminal domain, the pseudosubstrate site involved in binding and inactivation of the catalytic subunit, and two C-terminally located, closely spaced cyclic nucleotide binding domains.

10p system191 01-06-2013 38 4   Download

Connective tissue growth factor/hypertrophic chondrocyte specific gene product 24 (CTGF/Hcs24) promotes proliferation and differentiation of chondrocytes in culture. We investigated the roles of two major types of mitogen activated protein kinase (MAPK) in the promotion of proliferation and differentiation by CTGF/Hcs24. Here we report the effects of the MAPKK/MEK 1/2 inhibitor, PD098059, and p38 MAPK inhibitor, SB203580, in a human chondrosarcoma-derived chondrocytic cell line (HCS-2/8) and rabbit growth cartilage (RGC) cells treated with CTGF/ Hcs24....

8p system191 01-06-2013 42 3   Download

Calmodulin (CaM) is phosphorylated in vitro and in vivo by multiple protein-serine/threonine and protein-tyrosine kinases. Casein kinase II and myosin light-chain kinase are two of the well established protein-serine/threonine kinases implicated in this process. On the other hand, within the protein-tyrosine kinases involved in the phosphorylation of CaM are receptors with tyrosine kinase activity, such as the insulin receptor and the epidermal growth factor receptor, and nonreceptor protein-tyrosine kinases, such as several members of the Src family kinases, Janus kinase 2, and p38Syk....

13p research12 01-06-2013 46 6   Download

A splicing factor SF2/ASF is a natural substrate for the kinase activity of human topoisomerase I. This study demonstrates that SF2/ASF inhibits DNA cleavage by human topoisomerase I induced by the anti-cancer agent camptothecin. The inhibition is independent of the phosphorylation status of SF2/ASF. We show that the inhibition did not result from binding of SF2/ASF to DNA that would hinder interactions between topoisomerase I and DNA. Neither it was a consequence of a loss of sensitivity of the enzyme to camptothecin.

7p research12 01-06-2013 39 5   Download

The p25rum1 is an inhibitor of Cdc2 kinase expressed in fission yeast and plays an important role in cell-cycle control. As its amino-acid sequence suggests that p25rum1 has putative phosphorylation sites for mitogen-activated protein kinase (MAPK), we investigated the ability of MAPK to phosphorylate p25rum1. Direct in vitro kinase assay using GST-fusion proteins of wild-type as well as various mutants of p25rum1 demonstrated that MAPK phosphorylates the N-terminal portion of p25rum1 and residues Thr13 and Ser19 are major phosphorylation sites for MAPK....

11p research12 01-06-2013 47 4   Download

The regulator of ubiquitous kinase (Ruk) protein, also known as CIN85 or SETA, is an adaptor-type protein belonging to the CD2AP/CMS family. It was found in complexes with many signaling proteins, including phos1 phoinositol (PtdIns) 3-kinase (EC 2.7.1.137), Cbl, GRB2, p130Cas and Crk. Functional analysis of these interactions, implicated Ruk in the regulation of apoptosis, receptor endocytosis and cytoskeletal rearrangements.

7p research12 01-06-2013 28 4   Download

A systematic search for Escherichia coli proteins with the zinc-binding activity was performed using the assay of radioactive Zn(II) binding to total E. coli proteins fractionated by two methods of two-dimensional gel electrophoresis. A total of 30–40 radioactive spots were identified, of which 14 have been assigned from N-terminal sequencing.

11p research12 01-06-2013 36 3   Download

The effect of a-tocopheryl hemisuccinate (TS) on lipopolysaccharide (LPS)/interferon-c (IFN)-induced nitric oxide production in rat vascular smooth muscle cells (VSMC) was examined. The LPS/IFN-induced NO production was enhanced by TS but not by the other a-tocopherol (a-T) derivatives a-tocopheryl acetate (TA) and a-tocopheryl nicotinate (TN), or a-T itself. a-T, TA and TN inhibited the enhancement by TS of LPS/IFNinduced NO production.

6p research12 01-06-2013 39 4   Download

The structure of the N-terminal docking and dimerization domain of the type IIa regulatory subunit (RIIa D/D) of protein kinase A (PKA) forms a noncovalent stand-alone X-type four-helix bundle structural motif, consisting of two helix-loop-helix monomers. RIIa D/D possesses a strong hydrophobic core and two distinct, exposed faces. A hydrophobic face with a groove is the site of protein–protein interactions necessary for subcellular localization.

12p research12 01-06-2013 50 4   Download

A eukaryotic-type protein serine/threonine kinase, PknA, was cloned from Mycobacterium tuberculosis strain H37Ra. Sequencing of the clone indicated 100% identity with the published pknA sequence of M. tuberculosis strain H37Rv. PknA fused to maltose-binding protein was expressed in Escherichia coli; it exhibited a molecular mass of % 97 kDa. The fusion protein was purified from the soluble fraction by affinity chromatography using amylose resin.

8p research12 01-06-2013 42 3   Download

A cDNA encoding 6-phosphofructo-2-kinase/fructose-2,6bisphosphatase was isolated from a Spinacia oleracea leaf library and used to express a recombinant enzyme in Escherichia coli and Spodoptera frugiperda cells. The insoluble protein expressed in E. coli was purified and used to raise antibodies. Western blot analysis of a protein extract from spinach leaf showed a single band of 90.8 kDa. Soluble protein was purified to homogeneity from S. frugiperda cells infected with recombinant baculovirus harboring the isolated cDNA. ...

11p research12 01-06-2013 43 5   Download

Stress-activated protein kinase (SAPK) signaling plays essential roles in eliciting adequate cellular responses to stresses and proinflammatory cytokines. SAPK pathways are composed of three successive protein kinase reactions. The phosphorylation of SAPK signaling components on Ser/Thr or Thr/Tyr residues suggests the involvement of various protein phosphatases in the negative regulation of these systems.

7p research12 01-06-2013 54 4   Download

The CD53 antigen is a member of the tetraspanin membrane protein family that is expressed in the lymphoid-myeloid lineage. We have studied the implication of CD53 antigen in signal transduction by determining the effect of its ligation on the c-Jun N-terminal kinase (JNK) in different cell types. Ligation of the rat or human CD53 antigen induces a threeto fourfold transient activation of JNK activity that peaks at 3–5 min. The effect was detected by assaying the endogenous or exogenous (transfected) JNK activity....

10p research12 01-06-2013 44 6   Download