scholarly journals A Method for Direct Measurement of Protein Stability In Vivo

Author(s):  
Zoya Ignatova ◽  
Lila M. Gierasch
2019 ◽  
Vol 26 (5) ◽  
pp. 339-347 ◽  
Author(s):  
Dilani G. Gamage ◽  
Ajith Gunaratne ◽  
Gopal R. Periyannan ◽  
Timothy G. Russell

Background: The dipeptide composition-based Instability Index (II) is one of the protein primary structure-dependent methods available for in vivo protein stability predictions. As per this method, proteins with II value below 40 are stable proteins. Intracellular protein stability principles guided the original development of the II method. However, the use of the II method for in vitro protein stability predictions raises questions about the validity of applying the II method under experimental conditions that are different from the in vivo setting. Objective: The aim of this study is to experimentally test the validity of the use of II as an in vitro protein stability predictor. Methods: A representative protein CCM (CCM - Caulobacter crescentus metalloprotein) that rapidly degrades under in vitro conditions was used to probe the dipeptide sequence-dependent degradation properties of CCM by generating CCM mutants to represent stable and unstable II values. A comparative degradation analysis was carried out under in vitro conditions using wildtype CCM, CCM mutants and two other candidate proteins: metallo-β-lactamase L1 and α -S1- casein representing stable, borderline stable/unstable, and unstable proteins as per the II predictions. The effect of temperature and a protein stabilizing agent on CCM degradation was also tested. Results: Data support the dipeptide composition-dependent protein stability/instability in wt-CCM and mutants as predicted by the II method under in vitro conditions. However, the II failed to accurately represent the stability of other tested proteins. Data indicate the influence of protein environmental factors on the autoproteolysis of proteins. Conclusion: Broader application of the II method for the prediction of protein stability under in vitro conditions is questionable as the stability of the protein may be dependent not only on the intrinsic nature of the protein but also on the conditions of the protein milieu.


2017 ◽  
Vol 5 (13) ◽  
pp. 2445-2458 ◽  
Author(s):  
I. Mitch Taylor ◽  
Zhanhong Du ◽  
Emma T. Bigelow ◽  
James R. Eles ◽  
Anthony R. Horner ◽  
...  

First everin vivosensor for directly measuring cocaine concentration in the brainviaelectrochemical detection at DNA aptamer functionalized single shank, silicon-based neural recording probes.


2012 ◽  
Vol 172 (1) ◽  
pp. e55-e60 ◽  
Author(s):  
Carlo R. Bartoli ◽  
Sujith Dassanayaka ◽  
Kenneth Brittian ◽  
Arun C. Nadar ◽  
Mohamed A. Ismahil ◽  
...  

2009 ◽  
Vol 424 (2) ◽  
pp. 285-296 ◽  
Author(s):  
Jeong Hae Choi ◽  
Hyun Kook Cho ◽  
Yung Hyun Choi ◽  
JaeHun Cheong

HIF-1 (hypoxia inducible factor 1) performs a crucial role in mediating the response to hypoxia. However, other transcription factors are also capable of regulating hypoxia-induced target-gene transcription. In a previous report, we demonstrated that the transcription factor ATF-2 (activating transcription factor 2) regulates hypoxia-induced gene transcription, along with HIF-1α. In the present study, we show that the protein stability of ATF-2 is induced by hypoxia and the hypoxia-mimic CoCl2 (cobalt chloride), and that ATF-2 induction enhances HIF-1α protein stability via direct protein interaction. The knockdown of ATF-2 using small interfering RNA and translation-inhibition experiments demonstrated that ATF-2 plays a key role in the maintenance of the expression level and transcriptional activity of HIF-1α. Furthermore, we determined that ATF-2 interacts directly with HIF-1α both in vivo and in vitro and competes with the tumour suppressor protein p53 for HIF-1α binding. Collectively, these results show that protein stabilization of ATF-2 under hypoxic conditions is required for the induction of the protein stability and transactivation activity of HIF-1α for efficient hypoxia-associated gene expression.


2009 ◽  
Vol 36 (5) ◽  
pp. 861-871 ◽  
Author(s):  
Linda Foit ◽  
Gareth J. Morgan ◽  
Maximilian J. Kern ◽  
Lenz R. Steimer ◽  
Annekathrin A. von Hacht ◽  
...  
Keyword(s):  

Author(s):  
R. Griffith ◽  
H. Bergmann ◽  
F. A. Fry ◽  
D. Hickman ◽  
J.-L. Genicot ◽  
...  

Previous ICRU reports have dealt with the formulation and properties of tissue substitutes and phantoms that are used to calibrate in vivo measurement systems. This report provides guidance on the overall process of the direct measurement of radionuclides in the human body for radiation protection and medical applications. It addresses the detectors and electronics used for the measurement; methods of background reduction and control; measurement geometries for whole body, partial body or organ counting; physical and mathematical calibration methods; data analysis; and quality assurance. It is directed to readers who need practical advice on the establishment and operation of direct measurement facilities.


2005 ◽  
Vol 39 (1) ◽  
pp. 84-90 ◽  
Author(s):  
Zheping Huang ◽  
Jie Deng ◽  
Jimo Borjigin
Keyword(s):  

1996 ◽  
Vol 144 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Sakae Unezaki ◽  
Kazuo Maruyama ◽  
Jun-Ichi Hosoda ◽  
Itsuro Nagae ◽  
Yasuhisa Koyanagi ◽  
...  

1986 ◽  
Vol 240 (3) ◽  
pp. 765-769 ◽  
Author(s):  
L Hue ◽  
H S Sherratt

Treatment of rats with hypoglycaemic doses of hypoglycin has been shown to abolish the relative detritiation of [2-3H,U-14C]glucose [Osmundsen, Billington, Taylor & Sherratt (1978) Biochem. J. 170, 337-342], indicating that both the Cori and the glucose/glucose 6-phosphate cycles were inhibited in vivo. This inhibition was confirmed and, in addition, it was shown that the conversion in vivo of both [14C]lactate and [14C]fructose into glucose was decreased after hypoglycin treatment. These results suggest that hypoglycin poisoning results in the inhibition in vivo of glucose-6-phosphatase activity, which participates in the overall inhibition of gluconeogenesis and hypoglycaemia. Clofibrate feeding apparently protected the rats against the inhibition of the fructose-to-glucose conversion by hypoglycin. However, in isolated hepatocytes prepared from hypoglycin-treated rats, the conversion of [14C]fructose into glucose and the recycling of [2-3H,U-14C]glucose were not different from that in control hepatocytes. This suggests that the inhibition was lost during preparation of the hepatocytes. The direct measurement of glucose-6-phosphatase activity showed that it was inhibited when measured in concentrated, but not dilute, homogenates prepared from hypoglycin-treated rats.


Sign in / Sign up

Export Citation Format

Share Document