Proteins in cytoplasm

Elasticity measurements already have been used to detect the presence of crosslinking proteins in cytoplasmic extracts(24). If preformed actin chains are employed, assessment of the rheological state of a network directly provides information about the parameters of crosslinking. Moreover, chain growth can bg studied, although indirectly, through the effects of Cq, Uq, on the concentration of crosslinking sites Sy. 

Vigorous Ultra sonication or bead milling follow equipment instructions cell suspensions intracellular proteins in cytoplasm, periplasm, inclusion bodies small scale, release of nucleic acids may cause viscosity problems inclusion bodies must be resolubilised... 

Vincent A, Goldenberg N, Standart N, Civelli 0, Imaizumi-Scherrer T, Maundrell K, Scherrer K (1981) Potential role of mRNP proteins in cytoplasmic control of gene expression in duck erythroblasts. Mol Biol Rep 7 71-81... 

In addition to effects on biochemical reactions, the inhibitors may influence the permeability of the various cellular membranes and through physical and chemical effects may alter the structure of other subcellular structures such as proteins, nucleic acid, and spindle fibers. Unfortunately, few definite examples can be listed. The action of colchicine and podophyllin in interfering with cell division is well known. The effect of various lactones (coumarin, parasorbic acid, and protoanemonin) on mitotic activity was discussed above. Disturbances to cytoplasmic and vacuolar structure, and the morphology of mitochondria imposed by protoanemonin, were also mentioned. Interference with protein configuration and loss of biological activity was attributed to incorporation of azetidine-2-carboxylic acid into mung bean protein in place of proline. 

The nuclear pore complex, located in the nuclear envelope, contains more than 50 proteins. It allows diffusion of small proteins between cytoplasm and nucleoplasm. Larger molecules (>50kD) are selectively transported by an energy-dependent mechanism. 

The current functional model of o control is depicted in Fig. 2. In the absence of non-native proteins in the periplasm or outer membrane, o is sequestered by RseA acting as an anti-sigma factor. Tight binding of o requires the participation of RseB which might act as an co-anti-sigma factor. Upon accumulation of non-native proteins outside the cytoplasm, RseB is released from... 

The Ca transport and Ca -stimulated ATPase activity of sarcoplasmic reticulum is inhibited by 10-30nmol dicyclohexylcarbodiimide per mg protein in a Ca free medium [372]. A23187 enhanced the sensitivity of the enzyme to DCCD, while Ca or Sr at micromolar concentrations prevented the inhibition. Since Ca -loaded vesicles retained their sensitivity to DCCD in a Ca -free medium, the reactivity of the enzyme with DCCD is controlled by the occupancy of the high-affinity Ca sites on the cytoplasmic surface of the membrane. 

In contrast to these results, Ross et al. [33] found that antisera against a 20-amino acid peptide (Ser-613-Arg-632) of the cytoplasmic domain of the human Na /H exchanger recognized a 66-kDa protein in immunoblots of bovine renal brush border membranes. Since the purity of these membranes was not reported it is possible that this result was due to contamination with basolateral membranes (although the molecular mass would still differ from the basolateral Na /H exchanger in LLC-... 

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