Proteins In vitro

Organization into macromolecular structures. There are no apparent templates necessary for the assembly of muscle filaments. The association of the component proteins in vitro is spontaneous, stable, and relatively quick. Filaments will form in vitro from the myosins or actins from all three kinds of muscle. Yet in vitro smooth muscle myosin filaments are found to be stable only in solutions somewhat different from in vivo conditions. The organizing principles which govern the assembly of myosin filaments in smooth muscle are not well understood. It is clear, however, a filament is a sturdy structure and that individual myosin molecules go in and out of filaments whose structure remains in a functional steady-state. As described above, the crossbridges sticking out of one side of a smooth muscle myosin filament are all oriented and presumably all pull on the actin filament in one direction along the filament axis, while on the other side the crossbridges all point and pull in the opposite direction. The complement of minor proteins involved in the structure of the smooth muscle myosin filament is unknown, albeit not the same as that of skeletal muscle since C-protein and M-protein are absent. 

Clarke, C.F., Cheng, K., Frey, A.B., Stein, R., Hinds, P.W.. Levine, A.J. (1988). Purification of complexes of nuclear oncogene p53 with rat and E. coli heat shock protein In vitro dissociation of hsc70 and dnaK from murine p53 by ATP. Mol. Cell. Biol. 8, 1206-1215. 

Lactam antibiotics, such as cephalosporins, and penicillins, such as ampicillin (11) and aztreonam, covalently modify their protein targets. Alkyne-functionalized versions of these antibiotics, for example, AmpN (12), were used to probe various penicillin-binding proteins in vitro and in vivo using CC-ABPP [36,37],... 

Zitiianova and others (2006) examined the inhibitory effect of extracts from different kinds of fruits and vegetables on the oxidative damage to proteins in vitro. Dragsted and others (2004) investigated the relative influence of nutritive and nonnutritive factors in fruit and vegetables on oxidative damage and enzymatic defense. Jacob and others... 

Replacement of the famesyl group by lipid analogues could be performed for full length Ras proteins in vitro by means of the enzyme famesyltrans-ferase. When such partially modified Ras constructs were applied in Xenopus oocytes the cellular machinery completed modification (endoprotease activity, carboxymethylation and palmitoylation). In these cases the H-Ras famesyl group could be stripped off most of its isoprenoid features that distinguish it from a fatty add without any apparent effect on its ability to induce oocyte maturation and activation of mitogen-activated protdn kinase In contrast, replacement by the less hydrophobic isoprenoid geranyl causes severely delayed oocyte activation. 

Inoue, S., Tsuda, H., Tanaka, T., Kobayashi, M., Magoshi, Y., and Magoshi, J. (2003). Nanostructure of natural fibrous protein In vitro nanofabric formation of Sarnia cynthia ricini wild silk fibroin by self-assembling. Nano Lett. 3, 1329-1332. 

Tomiyama, T., Asano, S., Suwa, Y., Morita, T., Kataoka, K., Mori, H., andEndo, N. (1994). Rifampicin prevents the aggregation and neurotoxicity of amyloid beta protein in vitro. Biochem. Biophys. Res. Commun. 204, 76-83. 

Grover, R.L. and Sims, P. Enzyme-catalyzed reactions of polycyclic hydrocarbons with deoxyribonucleic acid and protein in vitro. Biochem. J. (1968) 110, 159-160. 

One important function of DUBs is the processing of ubiquitin or ubiquitin-like proteins to their mature forms. Ubiquitin is expressed in cells as either linear poly-ubiquitin or N-terminally fused to certain ribosomal proteins [79, 80]. These gene products are processed by DUBs to separate the ubiquitin into monomers and expose the gly-gly motif at the G-terminus. Many DUBs process linear polyubiquitin or Ub-fusion proteins in vitro, but this processing appears to take place cotransla-tionally in vivo and is extremely rapid. This makes analysis difficult and leaves unanswered the question of which DUBs actually perform this function in vivo. Multiple DUBs may be able to perform this processing at a physiologically relevant level since DUB deletions rarely shows processing defects [81]. 

Tau protein interacts with many other proteins that can contribute to abnormal fibrillogenesis. One example is a-synuclein, which induces fibrillization of tau. Coincubation of a-synnclein and tau synergistically promotes fibrillization of both proteins in vitro. Mice with a-synuclein mutation or a tau mutation exhibit filamen-tons inclusions of both proteins, which are abundant neuronal proteins that normally adopt an nnfolded conformation but polymerize into amyloid fibrils in... 

Metaboiism/Excretion- Nefazodone is extensively metabolized after oral administration by less than 1% is excreted unchanged in urine. The mean half-life ranged between 11 and 24 hours. Nefazodone is extensively (more than 99%) bound to human plasma proteins in vitro. 

Pharmacokinetics Following oral administration to healthy volunteers, mean peak plasma concentrations were achieved within 3 hours. Bupropion is 84% bound to human plasma proteins in vitro. Bupropion is extensively metabolized with a mean... 

Binding of entecavir to human serum proteins in vitro was approximately 13%. 

Lue NF, Chasman Dl, Buchman AR et al (1987) Interaction of GAL4 and GAL80 gene regulatory proteins in vitro. Mol Cell Biol 7 3446-3451... 

Oraumbo IF, Van Duuren BL. 1987. Time-related binding of the hepatocarcingon carbon tetrachloride to hepatic chromatin proteins in vitro. Carcinogenesis 8 855-856. 

Uehleke H, Hellmer KH, Tabarelli S. 1973. Binding of 14C-carbon tetrachloride to microsomal proteins in vitro and formation of CHC13 by reduced liver microsomes. Xenobiotica 3 1-11. 

In addition to CKle, a second casein kinase 1 orthologue, CK1(5, has been implicated in the mammalian circadian clock. CK15 and CKle both bind and phosphorylate mammalian PER proteins in vitro (Keesler et al 2000, Vielhaber et al 2000, Camacho et al 2001), and are physically associated with PER and CRY in vivo (Lee et al 2001). In tau mutants, PER proteins continue to be phosphorylated in spite of the lowered function measured for CKle in vitro (Lee et al 2001). It has been suggested that the residual phosphorylation might be supplied by PER-associated CK15 in the mutants, and that CKle and CK1(5 have overlapping functions in the mammahan circadian system (Lee et al 2001). 

Vile, G. R, and Tyrrell, R. M. 1995. UVA radiation-induced oxidative damage to lipids and proteins in vitro and in human skin fibroblasts is dependent on iron and singlet oxygen. Free Rad. Biol. Med. 18 721-22. 

Nagase T, Ishikawa K, Nakajima D, et al. (1997) Prediction of the coding sequences of unidentified human genes. Vll. The complete sequences of 100 new cDNA clones from brain which can code for large proteins in vitro DNA Res 4, 141-150. 

Exchange activity with Ras protein has been demonstrated for recombinant Sos protein in vitro-, however, this is much lower than the exchange activity of CDC25 protein in S. cerevisiae. 

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