+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Properties of strand displacement synthesis by Moloney murine leukemia virus reverse transcriptase: mechanistic implications

, : Properties of strand displacement synthesis by Moloney murine leukemia virus reverse transcriptase: mechanistic implications. Journal of Molecular Biology 278(3): 559-577

Previous results indicated that Moloney murine leukemia virus reverse transcriptase is capable of extensive synthesis under conditions where it must simultaneously displace a downstream non-template DNA strand. To investigate more fully the mechanistic basis for displacement synthesis and to characterize the activity with natural viral templates, displacement and non-displacement synthesis were compared under a variety of conditions using the viral long terminal repeat plus strand as the template. Although the rates of both displacement and non-displacement synthesis varied regionally over the template, on the average, displacement synthesis was slower by a factor of approximately 3 to 4. Surprisingly, with one particular primer situated downstream of the tRNA primer binding site, displacement synthesis was found to be at least tenfold more processive than non-displacement synthesis, approaching a value of 500 nucleotides. The sequence features associated with pausing during the two modes of synthesis are different in both nucleotide preference and position relative to the enzyme, suggesting that the enzyme contacts the DNA differently under the two modes of synthesis. It was found that pausing during displacement synthesis did not reflect those local regions of DNA with a predicted high degree of thermal stability. Moreover, the very similar effects of temperature on the rates of displacement and non-displacement synthesis make unlikely a strictly passive mechanism of displacement synthesis whereby breathing of the downstream duplex is sufficient for advancement of the polymerase. Together, these results suggest a mechanism of displacement synthesis in which reverse transcriptase actively participates in the process of strand separation in front of the translocating polymerase.


PMID: 9600839

DOI: 10.1006/jmbi.1998.1720

Other references

Hamood, Abdul N., 1993: The effect of the toxA regulatory gene, exoAR, on toxA transcription in the Pseudomonas aeruginosa strains PAO1 and PA103. Abstracts of the General Meeting of the American Society for Microbiology 93(0): 86

Jawor Eugeniusz, 1970: Structure of the deep substratum east of Krakow. Acta Geologica Polonica 20(4): 709-769

Wilairatana, P.; Silachamroon, U.; Krudsood, S.; Singhasivanon, P.; Treeprasertsuk, S.; Bussaratid, V.; Phumratanaprapin, W.; Srivilirit, S.; Looareesuwan, S., 1999: Efficacy of primaquine regimens for primaquine-resistant Plasmodium vivax malaria in Thailand. To define the current efficacy of Fansidar (pyrimethamine plus sulfadoxine), primaquine in a high dose, and artesunate for treating acute Plasmodium vivax malaria, a comparative clinical trial was conducted in an open-label study. Patients (15-65...

Baydur, A.; Sassoon, C.S.H.; Carlson, M., 1996: Measurement of lung mechanics at different lung volumes and esophageal levels in normal subjects: Effect of posture change. Lung elastance and resistance increase in the supine posture. To evaluate the effects of change in posture on regional lung mechanics at different lung volumes, lung elastance and resistance were measured at graded volume subdivisions and three es...

Gardiner S.M.; Compton A.M.; Bennett T., 1990: Regional hemodynamic effects of endothelin 1 and endothelin 3 in conscious long evans and brattleboro rats. 1 The regional haemodynamic effects of bolus doses (4 and 40 pmol) and infusions (12 and 120 pmol h-1) or endothelin-3 and endothelin-1 were assessd in conscious, Long Evans and Brattleboro (i.e. vasopressin-deficient) rats, chronically-instrument...

Foucan, L.; Haddad, A.; Genevier, I.; Samuel, Y.; Salmi, R.L., 1999: Sokolow-Lyon voltage criteria in sickle cell patients. The electrocardiogram remains the most commonly used method of cardiac assessment in developing countries. To determine the prevalence of electrocardiographic left ventricular hypertrophy (LVH) and the clinical significance of Sokolow-Lyon voltage...

Zheng, W.; Blaner, W.S.; Zhao, Q., 1999: Inhibition by lead of production and secretion of transthyretin in the choroid plexus: its relation to thyroxine transport at blood-CSF barrier. Long-term, low-dose Pb exposure in rats is associated with a significant decrease in transthyretin (TTR) concentrations in the CSF. Since CSF TTR, a primary carrier of thyroxine in brain, is produced and secreted by the choroid plexus, in vitro st...

Iida, M.; Yao, T.; Ohsato, K.; Itoh, H.; Watanabe, H., 1980: Diagnostic value of intraoperative fiberscopy for small-intestinal polyps in familial adenomatosis coli. X-ray examination and intraoperative fiberscopy of the small intestine were performed in 20 patients with familial adenomatosis coli. Roentgenographic study detected polypoid lesions in the upper jejunum in 2 patients (10%), and in the terminal il...

Larson, M.M., 1967: Effect of temperature on initial development of ponderosa pine seedlings from three sources. Seedlings of Pinus ponderosa Laws. from seeds collected in Arizona, California, and South Dakota were grown for 6 weeks under various combinations of constant air and soil temperatures from 7[degree] C to 31[degree]C, and combinations of day and n...

Grandchamp, B.; Beaumont, C.; D.V.rneuil, H., 1985: Accumulation of porphobilinogen deaminase, uroporphyrinogen decarboxylase, and a- and b-globin mRNAs during differentiation of mouse erythroleukemic cells. Effects of succinylacetone. The Journal of Biological Chemistry 260: 30-5