scholarly journals Ko-translationale Assemblierung von Proteinkomplexen

BIOspektrum ◽  
2021 ◽  
Vol 27 (7) ◽  
pp. 723-726
Author(s):  
Kai Fenzl ◽  
Günter Kramer ◽  
Bernd Bukau
Keyword(s):  
Biological Activity ◽  
Cellular Proteins ◽  
General View

AbstractThe majority of cellular proteins exerts their biological activity as oligomeric complexes. The general view was that complexes form by random collision of folded subunits in the cytosol. Recent studies question this view by demonstrating that a surprisingly high number of complexes are formed during translation. Co-translational assembly occurs by interaction either of fully synthesized subunits with nascent partner subunits, or of two nascent polypeptides exposed by proximal ribosomes.

Mapping of cellular protein-binding sites on the products of early-region 1A of human adenovirus type 5

1988 ◽  
Vol 8 (9) ◽  
pp. 3955-3959 ◽  
Author(s):  
C Egan ◽  
T N Jelsma ◽  
J A Howe ◽  
S T Bayley ◽  
B Ferguson ◽  
...  
Keyword(s):  
Biological Activity ◽  
Binding Sites ◽  
Human Adenovirus ◽  
Adenovirus Type ◽  
Cellular Protein ◽  
Cellular Proteins ◽  
Deletion Mutants ◽  
Protein Binding Sites ◽  
Amino Terminal ◽  
Adenovirus Type 5

The binding sites for the 300-, 107-, and 105-kilodalton cellular proteins which associate with human adenovirus type 5 E1A products were studied with E1A deletion mutants. All appeared to bind to the amino-terminal half of E1A products in regions necessary for oncogenic transformation. These results suggest that these cellular species may be important for the biological activity of E1A products.

Assessment of the Inhibition of Ricin Toxicity by Lactose in Milk

2013 ◽  
Vol 76 (12) ◽  
pp. 2037-2039 ◽  
Author(s):  
STEPHEN E. LUMOR ◽  
BRONWYN D. DEEN ◽  
IAN RONNINGEN ◽  
KENNETH SMITH ◽  
NEAL R. FREDRICKSON ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Biological Activity ◽  
Hela Cells ◽  
Liquid Scintillation ◽  
Lethal Dose ◽  
Bovine Milk ◽  
Inhibitory Effect ◽  
Cellular Proteins ◽  
Inhibit Protein Synthesis

The effect of lactose at the concentration typically found in milk (134 mM) on the ability of ricin to inhibit protein synthesis in HeLa cells was studied. Ricin (0.001 to 300 μg/ml) that was either not treated or treated with 134 mM lactose was added to test tubes containing 1 ml of HeLa cells (approximately 3 × 105 cells in a low-leucine medium). After 2 h of incubation at 37°C, 0.5 μCi of l-[U-14C]-leucine was added to each tube and incubated for another 60 min. The cells were harvested by centrifugation and lysed, and cellular proteins were separated. The amount of radioactivity incorporated into the proteins was determined by liquid scintillation. The biological activity of ricin, i.e., the amount of radioactivity in a sample relative to that of the control (cells not treated with ricin), was calculated for each treatment. The inhibitory effect of 134 mM lactose on the biological activity of ricin was only significant at concentrations of ricin below 1 μg/ml. At higher ricin concentrations, the effect of 134 mM lactose decreased as the concentration of ricin increased, resulting in an increase in the inhibition of proteins synthesis. Our results also indicated that bovine milk, when used in place of 134 mM lactose, was more effective for reducing the activity of ricin at concentrations below 1 μg/ml but was ineffective against ricin concentrations greater than 1 μg/ml. These results suggest that milk may not protect against ricin intoxication at the concentration (0.89 μg/ml) equivalent to the lowest limit of its 50% lethal dose for a 20-kg child consuming 225 ml (8 oz) of milk.

Mechanisms of Cotranslational Maturation of Newly Synthesized Proteins

2019 ◽  
Vol 88 (1) ◽  
pp. 337-364 ◽  
Author(s):  
Günter Kramer ◽  
Ayala Shiber ◽  
Bernd Bukau
Keyword(s):  
Biological Activity ◽  
Functional State ◽  
Cellular Proteins ◽  
Critical Importance ◽  
Comprehensive Understanding ◽  
Sequence Of Events ◽  
Interaction Partners ◽  
The Way

The timely production of functional proteins is of critical importance for the biological activity of cells. To reach the functional state, newly synthesized polypeptides have to become enzymatically processed, folded, and assembled into oligomeric complexes and, for noncytosolic proteins, translocated across membranes. Key activities of these processes occur cotranslationally, assisted by a network of machineries that transiently engage nascent polypeptides at distinct phases of translation. The sequence of events is tuned by intrinsic features of the nascent polypeptides and timely association of factors with the translating ribosome. Considering the dynamics of translation, the heterogeneity of cellular proteins, and the diversity of interaction partners, it is a major cellular achievement that these processes are temporally and spatially so precisely coordinated, minimizing the generation of damaged proteins. This review summarizes the current progress we have made toward a comprehensive understanding of the cotranslational interactions of nascent chains, which pave the way to their functional state.

scholarly journals MODERN ETHIOTROPIC CHEMOTHERAPY OF HERPESVIRUS INFECTIONS: ADVANCES, NEW TRENDS AND PERSPECTIVES. ALPHAHERPESVIRUSES (PART II)

2018 ◽  
Vol 63 (4) ◽  
pp. 149-159
Author(s):  
V. L. Andronova
Keyword(s):  
Drug Resistance ◽  
Biological Activity ◽  
Dna Polymerase ◽  
Viral Proteins ◽  
Modified Nucleosides ◽  
Cellular Proteins ◽  
Viral Dna ◽  
Biological Target ◽  
New Compounds

A key role in the treatment of herpesviral infections is played by modified nucleosides and their predecessors - acyclovir, its L-valine ester (valaciclovir) and famciclovir (prodrug of penciclovir). The biological activity of compounds of this class is determined by their similarity to natural nucleosides. After phosphorylation by viral thymidine kinase and then cell enzymes to the triphosphate forms, acyclovir and penciclovir inhibit the activity of viral DNA polymerase and synthesis of viral DNA. The increasing role of herpesvirus infections in human infectious pathology, as well as the development of drug resistance in viruses, mainly in patients with immunodeficiencies of various origins, necessitate the search for new compounds possessing anti-herpesvirus activity, using as a biological target not DNA polymerase, but other viral proteins and enzymes, unique or different from cellular proteins, performing similar functions.

scholarly journals SUMOylation Wrestles With the Occurrence and Development of Breast Cancer

2021 ◽  
Vol 11 ◽  
Author(s):  
Yuanyuan Qin ◽  
Hong Yuan ◽  
Xu Chen ◽  
Xinyi Yang ◽  
Zhengcao Xing ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Biological Activity ◽  
Effective Treatment ◽  
Cellular Localization ◽  
Therapeutic Strategies ◽  
Cellular Proteins ◽  
Important Process ◽  
Comprehensive Understanding ◽  
Detailed Mechanism ◽  
Cellular Processes

Breast cancer has the highest incidence among cancers and is the most frequent cause of death in women worldwide. The detailed mechanism of the pathogenesis of breast cancer has not been fully elucidated, and there remains a lack of effective treatment methods for the disease. SUMOylation covalently conjugates a large amount of cellular proteins, and affects their cellular localization and biological activity to participate in numerous cellular processes. SUMOylation is an important process and imbalance of SUMOylation results in the progression of human diseases. Increasing evidence shows that numerous SUMOylated proteins are involved in the occurrence and development of breast cancer. This review summarizes a series of studies on protein SUMOylation in breast cancer in recent years. The study of SUMOylated proteins provides a comprehensive understanding of the pathophysiology of breast cancer and provides evolving therapeutic strategies for the treatment of breast cancer.

scholarly journals Mapping of cellular protein-binding sites on the products of early-region 1A of human adenovirus type 5.

1988 ◽  
Vol 8 (9) ◽  
pp. 3955-3959 ◽  
Author(s):  
C Egan ◽  
T N Jelsma ◽  
J A Howe ◽  
S T Bayley ◽  
B Ferguson ◽  
...  
Keyword(s):  
Biological Activity ◽  
Binding Sites ◽  
Human Adenovirus ◽  
Adenovirus Type ◽  
Cellular Protein ◽  
Cellular Proteins ◽  
Deletion Mutants ◽  
Protein Binding Sites ◽  
Amino Terminal ◽  
Adenovirus Type 5

The binding sites for the 300-, 107-, and 105-kilodalton cellular proteins which associate with human adenovirus type 5 E1A products were studied with E1A deletion mutants. All appeared to bind to the amino-terminal half of E1A products in regions necessary for oncogenic transformation. These results suggest that these cellular species may be important for the biological activity of E1A products.

Statistical Study of the Rotation Effect of Am Stars

1976 ◽  
Vol 32 ◽  
pp. 675-683
Author(s):  
Keiichi Kodaira
Keyword(s):  
Statistical Study ◽  
Rotation Velocity ◽  
General View ◽  
Slow Rotation ◽  
Rotation Effect

SummaryExcess of [m1] index of Am stars, relative to normal stars, is statistically found to be correlated with rotation velocity; the coefficient is estimated at ∆׀m1׀ /∆V(km/sec) ˜ - 0.0007 among Am stars. This result supports the general view that slow rotation is essential for Am phenomena.

Virus-Like Particles in a Human Breast Cancer: Structural Similarity to Previously Reported Particles

1973 ◽  
Vol 31 ◽  
pp. 378-379
Author(s):  
G. Kasnic ◽  
S. E. Stewart ◽  
C. Urbanski
Keyword(s):  
Breast Cancer ◽  
Biological Activity ◽  
Human Breast Cancer ◽  
Osteogenic Sarcoma ◽  
Human Tumor ◽  
Structural Similarity ◽  
Cell Tumor ◽  
Human Breast ◽  
Human Tumor Cell ◽  
Type Particle

We have reported the maturation of an intracisternal A-type particle in murine plasma cell tumor cultures and three human tumor cell cultures (rhabdomyosarcoma, lung adenocarcinoma, and osteogenic sarcoma) after IUDR-DMSO activation. In all of these studies the A-type particle seems to develop into a form with an electron dense nucleoid, presumably mature, which is also intracisternal. A similar intracisternal A-type particle has been described in leukemic guinea pigs. Although no biological activity has yet been demonstrated for these particles, on morphologic grounds, and by the manner in which they develop within the cell, they may represent members of the same family of viruses.

Effects of Vincristine on Endothelial Microtubules in the Spinal Cord

1976 ◽  
Vol 34 ◽  
pp. 58-59
Author(s):  
John L. Beggs ◽  
John D. Waggener ◽  
Wanda Miller
Keyword(s):  
Spinal Cord ◽  
Biological Activity ◽  
Horseradish Peroxidase ◽  
Transport Mechanism ◽  
Vasogenic Edema ◽  
Vesicular Transport ◽  
Close Proximity

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.

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