Plasma membrane

TỔ CHỨC CỦA CƠ THỂ SỐNG CÁC ĐẶC TRƯNG CỦA SINH VẬT.Sinh vật được cấu tạo từ tế bào triển.. Trao đổi chất. Chuyển động Sinh vật trả lời lại các kích thích Sinh sản . Tiến hoá và thích nghi với môi trường.. Màng tế bào (Plasma membrane) Vách tế bào thực vật.Nhân tế bào.Tế bào chất . Các bào quan khác đa bào cấu tạo các mô chính ở thực vật hạt kín Cấu tạo các mô chính ở động vật đa ...

81p hoangyen999 04-05-2013 166 33   Download

Màng sợi cơ gồm một màng tế bào thực sự gọi là màng sinh chất (tiếng Anh: plasma membrane) và một lớp vỏ mỏng bao bọc bên ngoài, lớp vỏ này chứa nhiều sợi collagen. Ở mỗi tận cùng của sợi cơ, lớp vỏ mỏng hòa màng với sợi gân. Sau đó các sợi gân tập trung thành từng bó để tạo ra gân của cơ và bám vào gân (tendon).

35p tieulaubau 21-06-2011 76 10   Download

Basic Cell Biology I. Cytoplasm A. Plasma membrane B. Mitochondria C. Ribosomes D. Endoplasmic reticulum 1. Rough 2. Smooth E. Golgi apparatus F. Lysosomes G. Cytoskeleton II. Nucleus A. Nuclear Envelope B. Chromatin C. Nucleolus D. Nuclear matrix III. Cell division .© 2002 by Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, and Peter Walter. .Asymmetrical arrangement of phospholipids in plasma membrane ATP-dependent phospholipid translocase .Molecular Cell Biology, Lodish et al., 4th edition. .Figure 2—1.

68p whitedaisy1010 26-02-2013 64 12   Download

Subunits (a, b and c) of the interleukin-2 receptor complex (IL-2R) are involved in both proliferative and activationinduced cell death (AICD) signaling of T cells. In addition, the signaling b and c chains are shared by other cytokines (e.g. IL-7, IL-9, IL-15). However, the molecular mechanisms responsible for recruiting/sorting the a chains to the signaling chains at the cell surface are not clear.

10p research12 01-06-2013 33 5   Download

As an adaptation process to the growth retardation provoked by the presence of nonlethal concentrations of ergosterol biosynthesis inhibitors, Ustilago maydis alters the ratio of linoleic to oleic acid bound to plasma membrane ´ complex lipids [Hernandez, A., Cooke, D.T., Lewis, M. & Clarkson, D.T. (1997) Microbiology 143, 3165–3174]. This alteration increases plasma membrane H+-ATPase hydrolytic activity.

6p research12 01-06-2013 41 4   Download

Lipid rafts are liquid-ordered membrane microdomains with a unique protein and lipid composition found on the plasma membrane of most, if not all, mammalian cells. A large number of signalling molecules are concentrated within rafts, which have been proposed to function as signalling centres capable of facilitating efficient and specific signal transduction. This review summarizes current knowledge regarding the composition, structure, and dynamic nature of lipid rafts, as well as a number of different signalling path- ways that are compartmentalized within these microdomains....

16p research12 01-06-2013 41 3   Download

The Na + /H + exchanger is a ubiquitous membrane protein of bacteria, plants and mammals. The first isoform discov-ered (NHE1) is present on the mammalian plasma mem-brane and transports oneH + out of cells inexchange for one extracellular Na + . With solubilization in standard SDS/ PAGE buffer, this protein had a high tendency to aggregate when subjected to elevated temperature. The aggregates were stable and did not dissociate in high concentrations of SDSor 2-mercaptoethanol.

9p research12 29-04-2013 50 3   Download

Undifferentiated human promyelocytic leukemia HL-60 cells show little or no superoxide production, but generate a very low O2 – concentration upon incubation with all-trans-retinoic acid (ATRA). Its production reaches a maximum within 20 h, and thereafter is maintained at an almost con-stant level. The differentiated cells show phorbol 12-myri-state 13-acetate (PMA)-stimulatedNADPHoxidase activity consistent with the amount of gp91phox(phagocytic oxid-ase) expressed in the plasma membrane.

8p research12 29-04-2013 37 5   Download

Na + /K + -ATPase as an energy transducing ion pump has beenstudiedextensivelysince itsdiscovery in1957.Although early findings suggested a role for Na + /K + -ATPase in regulation of cell growth and expression of various genes, only in recent years the mechanisms through which this plasma membrane enzyme communicates with the nucleus have been studied.

6p research12 29-04-2013 34 4   Download

Erythroid dematin is a major component of red blood cell junctional complexes that link the spectrin±actin cytoskel-eton to the overlying plasma membrane. Transcripts of dematinarewidelydistributed includinghumanbrain, heart, lung, skeletalmuscle, andkidney.Invitro, dematinbinds and bundles actin ®laments in a phosphorylation-dependent manner. The primary structure of dematin consists of a C-terminal domain homologous to theÔheadpieceÕ domain of villin, an actin-binding protein of the brush border cyto-skeleton. ...

12p research12 23-04-2013 44 3   Download

Translocation through the plasma membrane is a major limiting step for the cellular delivery of macromolecules. A promising strategy to overcome this problem consists in the chemical conjugation (or fusion) to cell penetrating peptides (CPP) derived from proteins able to cross the plasma membrane. A large number of di€erent cargo mol-ecules such as oligonucleotides, peptides, peptide nucleic acids, proteins or even nanoparticles have been internalized in cells by this strategy.

8p research12 23-04-2013 33 4   Download

The protein-modifying agent arsenite stimulates glucose uptake in 3T3-L1 adipocytes. In the current study we have analysed the signalling pathways that contribute to this response. By subcellular fractionation we observed that arsenite, like insulin, induces translocation of the GLUT1 and GLUT4 glucose transporters from the low-density membrane fraction to the plasma membrane. Arsenite did not activate early steps of the insulin receptor (IR)-signalling pathway and the response was insensitive to inhibition of phosphatidylinositol-3¢-kinase (PI-3¢)kinaseby wortman-nin. ...

13p tumor12 20-04-2013 37 3   Download

aIIbb3, a member of the integrin family of adhesive protein receptors, is the most abundant glycoprotein on platelet plasma-membranes and binds to adhesive proteins via the recognition of short amino acid sequences, for example the ubiquitous RGD motif.However, elucidation of the ligand-binding domains of the receptor remains controversial, mainly owing to the fact that integrins are conformationally labile during purification and storage.

8p tumor12 20-04-2013 49 3   Download

The Tat system catalyzes the transport of folded globular proteins across the bacterial plasma membrane and the chloroplast thylakoid. It recognizes cleavable signal peptides containingacritical twin-argininemotif but little isknownof the overall structure of these peptides. In this report, we have analyzed the secondary structure of the SufI signal peptide, together with those of two nonfunctional variants in which the region around the twin-arginine, RRQFI, is replaced by KKQFI or RRQAA.

8p tumor12 20-04-2013 49 3   Download

Engineered yeast cells efficiently convert ergosta-5-eneol to pregnenolone and progesterone provided that endogenous pregnenolone acetylase activity is disrupted and that heterologous sterolD7-reductase, cytochrome P450 side chain cleavage (CYP11A1) and 3b hydroxysteroid dehydrogenase/isomerase (3b-HSD) activities are present. CYP11A1activity requires the expressionof themammalian NADPH-adrenodoxin reductase (Adrp) and adrenodoxin (Adxp) proteins as electron carriers.

13p tumor12 20-04-2013 31 3   Download

Previously, we isolated a 4-kDa peptide capable of binding to a 43-kDa receptor-like protein and stimulating protein kinase activity of the 43-kDa protein in soybean. Both of them were found to localize in the plasma membranes and cell walls. Here, we report the physiological effects of 4-kDa peptide expressed transiently in the cultured carrot and bird’s-foot trefoil cells transfected with pBI 121 plas-mid containing the 4-kDa peptide gene.

8p tumor12 20-04-2013 48 4   Download

Several crystal andNMRstructures of calmodulin (CaM)in complex with fragments derived from CaM-regulated pro-teins have been reported recently and reveal novel ways for CaMto interact with its targets. This review will discuss and compare features of the interaction between CaM and its target domains derived from the plasma membrane Ca 2+ -pump, the Ca 2+ -activated K + -channel, the Ca 2+ / CaM-dependent kinase kinase and the anthrax exotoxin.

11p tumor12 20-04-2013 28 4   Download

Antioxidant protein 2 (AOP2) is a member of a family of thiol-specific antioxidants, recently renamedperoxiredoxins, that evolvedas part of anelaborate systemtocounteract and control detrimental effects of oxygen radicals. AOP2 is found in endothelial cells, erythrocytes, monocytes, T andB cells, but not in granulocytes. AOP2 was found solely in the cytoplasm and was not associated with the nuclear or membrane fractions; neither was it detectable in plasma.

8p tumor12 20-04-2013 36 2   Download

Leukocytes and other cells show an enhanced intensity of mobile lipid in their 1 H NMR spectra under a variety of conditions.Such conditions include stimulation, which has recently been shown to involve detergent-resistant, plasma membranedomains (DRMs)oftencalled lipidrafts.As there ismuchspeculationsurrounding theoriginof cellularNMR-visible lipid, we analysed subcellular fractions, including DRMs, by NMR spectroscopy.

10p fptmusic 16-04-2013 46 3   Download

Bilitranslocase is a carrier protein localized at the basolateral domain of the hepatocyte plasma membrane. It transports various organic anions, including bromosulfophthalein and anthocyanins. Functional studies in subcellular fractions enriched in plasma membrane revealed a high-affinity binding site for bilirubin, associated with bilitranslocase.

14p fptmusic 12-04-2013 40 4   Download