Proteins In vivo

Patel MB, Patel CN, Rajashekara V, et al Opioid agonists differentially regulate U-opioid receptors and trafficking proteins in vivo. Mol Pharmacol 62 1464-1470, 2002... 

Frydman J Folding of newly translated proteins in vivo The role of molecular chaperones. Annu Rev Biochem 2001 70 603. Radord S Protein folding Progress made and promises ahead. 

These bis(thiolato)gold(I) complexes are useful models for providing insights into the chemistry of the end products of the reactions between 1 1 gold thiolates and any excess (including other) thiol, including some reactions with proteins in vivo. 

Morosinotto, T., Baronio, R., and Bassi, R. 2002. Dynamics of chromophore binding to Lhc proteins in vivo and in vitro during the operation of the xanthophyll cycle. J. Biol. Chem. 277 36913-36920. 

Robert, B., Horton, R, Pascal, A., and Ruban, A.V. 2004. Insights into the molecular dynamics of plant lightharvesting proteins in vivo. Trends in Plant Science 9 385-390. 

The serum L-PGDS/p-trace concentration shows a circadian variation with a nocturnal increase, which is suppressed during total sleep deprivation but not affected by deprivation of REM sleep (Jordan et ah, 2004). Whether or not L-PGDS is a dual-function protein in vivo and is involved in the production of PGD2 as well as in the transport of PGD2 or some other compound(s) remains to be elucidated. 

The potential of live cell imaging to address mechanisms of cellular biology is ever expanding. Directed protein-tagging techniques have been used to visualize nascent versus mature protein in vivo (Rodriguez et al., 2006). This technique involves the use of arsenic-based dyes, such as FiAsH or ReAsH, which bind to tetracysteine (TC) tags (Zhang et al, 2002). In addition, photo-activatable variants of GFP have been shown to determine the kinetics of protein movement in live cells (Patterson and Lippincott-Schwarz, 2002). Furthermore, techniques such as FRET and the... 

Staudinger ligation techniques also can be used to detect post-translational modification of proteins in vivo. Hang et al. (2007) developed a method to monitor fatty acid acylation of proteins using azido-fatty acids fed to cells. The two major types of fatty acid acylation,... 

Orlando, V. (2000) Mapping chromosomal proteins in vivo by formaldehyde-crosslinked-chromatin immunoprecipitation. Trends Biochem. Sci. 3, 99-104. 

Cyt c is one of most important and extensively studied electron-transfer proteins, partly because of its high solubility in water compared with other redox-active proteins. In vivo, cyt c transfers an electron from complex III to complex IV, membrane-bound components of the mitochondrial electron-transfer chain. The electrochemical interrogation of cyt c has, however, been hindered because the redox-active heme center is... 

Some efforts have been taken to obtain the electrochemical response of Hb at solid electrode surfaces. Fan s electrochemical researches revealed that the electron-transfer reactivity of Hb could be greatly enhanced, simply by treating it with an organic solvent, dimethyl sulfoxide (DMSO) [115], Hb can also achieve its direct electron transfer in /V,/V-dimcthy I form am idc (DMF) film, as Xu [116] reported. These, therefore, suggested that there are many different factors that regulate electron-transfer reactivity of proteins. It also pointed out the complicated and precise regulation mechanisms of proteins in vivo. 

Proteins in vivo protein-protein interactions, protein folding kinetics, protein subunit exchange, enzyme activity assay, etc. 

E. coli DegP has the ability to stabilize and support the refolding of several nonnative proteins in vivo and in vitro (Spiess et al. 1999 Misra et al. 2000). Possible... 

Adamietz P, Rudolph A (1984) ADP-ribosylation of nuclear proteins in vivo. Identification of histone H2B as a major acceptor for mono- and poly(ADP-ribose) in dimethyl sulfate-treated hepatoma AH 7974 cells. J Biol Chem 259 6841-6846... 

The regulatory roles of 14-3-3 proteins are realized by their binding to the phosphothreonine or phospho-serine motifs in the targets. Yao etal suggested that the phosphorylated Arg-X-Ser-X motif in the C-termini of ACS of types 1 and 2 is a potential binding site of 14-3-3 proteins in vivo and thus 14-3-3 proteins can play some role in the protection of ACS polypeptides from proteasomal degradation. 

It has recently been shown that some phosphorylations may be useful only to activate a protein and once in its active form or complexed, phosphorylation is no longer needed (Scheme 3). Karwowska-Desaulniers et ak recently hypothesized that phosphorylation of histone deacetylase 1 (HDACl) at two key residues is important for complex formation of active protein in vivo. However, when the phosphorylation sites were mutated to alanine, no active protein was expressed, yet complex formation was still observed. Even when native protein was expressed and dephosphorylated, complex formation and activity were still observed. The complex formation is still not fully understood the complexes are thought to place HDAC in the correct position. No active noncomplexed HDAC has been generated in order to study the effects of complexation. Interestingly, when HDACl was expressed in bacteria and subsequently phosphorylated there was no... 

Another unnatural amino acid (28), the (3-diketone, has also been genetically incorporated and used in vitro to label proteins with hydroxylamine derivatives of biotin or fluorescent dyes, thereby increasing the number of unique chemical handles that can be genetically incorporated into proteins in vivo. 

Recent advances in mass spectrometry (MS) technology have provided researchers with an unparalleled ability to identify the types and patterns of secondary biochemical modifications found on proteins in living cells. Matrix-assisted laser desorption/ionization-MS (MALDI-MS) analyses have shown, for example, that HMGA proteins in vivo are simultaneously subject to complex patterns of phosphorylation, acetylation and methylation and that, within the same cell type, different isoforms of these proteins can exhibit quite different modification patterns [33]. Furthermore, these in vivo modifications have been demonstrated to markedly alter the binding affinity of HMGA proteins for both DNA and chromatin substrates in vitro [33]. Nevertheless, due to their number and complexity, it has been difficult to determine the actual biological function(s) played by these biochemical modifications in living cells. 

Drugs that specifically inactivate or cross-link HMGA proteins in vivo... 

It has been known for some time that certain bromodomains, sequence elements found in many chromatin associated proteins and most HATs [79], bind preferentially to acetylated peptides in in vitro binding assays, leading to speculation that acetylated histone tails could form targets for the binding of bromodomain-containing proteins in vivo [80,81]. Recent experiments provide direct evidence for this. 

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