دورية أكاديمية
Inhibition of ribozymes by deoxyribonucleotides and the origin of DNA.
| العنوان: | Inhibition of ribozymes by deoxyribonucleotides and the origin of DNA. |
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| المؤلفون: | León PE; School of Medicine and Cell and Molecular Biology Research Center (CIBCM), Universidad de Costa Rica, San José, Costa Rica. PELA@cariari.ucr.ac.cr |
| المصدر: | Journal of molecular evolution [J Mol Evol] 1998 Aug; Vol. 47 (2), pp. 122-6. |
| نوع المنشور: | Journal Article |
| اللغة: | English |
| بيانات الدورية: | Publisher: Springer-Verlag Country of Publication: Germany NLM ID: 0360051 Publication Model: Print Cited Medium: Print ISSN: 0022-2844 (Print) Linking ISSN: 00222844 NLM ISO Abbreviation: J Mol Evol Subsets: MEDLINE |
| أسماء مطبوعة: | Original Publication: Berlin, New York, Springer-Verlag. |
| مواضيع طبية MeSH: | DNA* , Evolution, Molecular* , Models, Theoretical*, Deoxyribonucleotides/*pharmacology , RNA, Catalytic/*antagonists & inhibitors, DNA-Directed RNA Polymerases ; Mutation ; RNA-Directed DNA Polymerase ; Ribonucleotide Reductases |
| مستخلص: | Two catalytic functions were required, minimally, for the appearance of DNA in evolution: a ribonucleotide reductase (RNR) and a reverse transcriptase (RT). If one accepts the explanatory strength of the RNA world model, it is clear that DNA molecules arose in the RNA world at some stage during the early evolution of cells. I suggest that competition for limited and valuable resources such as nucleotides, amino acids, and sugars made an early appearance among RNA cells, RNA viruses, viroids, and RNA plasmids. Structural and functional similarities between the different types of polymerases favor the simple hypothesis that the first RTs were RNA polymerase mutants that preferentially joined together preexisting deoxyribonucleotide triphosphates (dNTPs) using RNA templates. What was the role of dNTPs inside cells before DNA was synthesized and tested by natural selection? The oxygen atom that is removed by the reductase is of crucial importance to many ribozyme functions, since the 2'-OH is a strong nucleophile that forms transitional states during catalysis. Consequently, a RNR may have been used by cellular parasites to inhibit ribozyme action. Thus, DNA may have been, initially, an inert by-product of retrotranscription in lineages that acquired RTs and could synthesize DNA molecules using cellular RNA templates to detoxify the intracellular environment. DNA was useless as template until a transcriptase (DNA-dependent RNA polymerase) evolved that could copy (-)DNA to reconstitute the (+)RNA genome, indeed a successful way of confronting ribonuclease threats in the RNA world. |
| المشرفين على المادة: | 0 (Deoxyribonucleotides) 0 (RNA, Catalytic) 9007-49-2 (DNA) EC 1.17.4.- (Ribonucleotide Reductases) EC 2.7.7.49 (RNA-Directed DNA Polymerase) EC 2.7.7.6 (DNA-Directed RNA Polymerases) |
| تواريخ الأحداث: | Date Created: 19980807 Date Completed: 19980909 Latest Revision: 20190905 |
| رمز التحديث: | 20231215 |
| DOI: | 10.1007/pl00006368 |
| PMID: | 9694660 |
| قاعدة البيانات: | MEDLINE |
Find this article in full text from Springer Verlag. 
Full Text Finder | تدمد: | 0022-2844 |
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| DOI: | 10.1007/pl00006368 |