The Prebiotic Synthesis of Modified Purines and Their Potential Role in the RNA World

1999 ◽  
Vol 48 (6) ◽  
pp. 631-637 ◽  
Author(s):  
Matthew Levy ◽  
Stanley L. Miller
Keyword(s):  
Potential Role ◽  
Rna World ◽  
Prebiotic Synthesis

scholarly journals A model for the emergence of RNA from a prebiotically plausible mixture of ribonucleotides, arabinonucleotides and 2’-deoxynucleotides

2019 ◽  
Author(s):  
Seohyun Chris Kim ◽  
Lijun Zhou ◽  
Wen Zhang ◽  
Derek K. O’Flaherty ◽  
Valeria Rondo-Brovetto ◽  
...  
Keyword(s):  
Rna Synthesis ◽  
Rna World ◽  
Random Sequence ◽  
Prebiotic Synthesis ◽  
Primer Extension ◽  
Complex Mixtures ◽  
Essential Step ◽  
Simultaneous Synthesis ◽  
The Difference ◽  
Chimeric Oligonucleotides

AbstractThe abiotic synthesis of ribonucleotides is thought to have been an essential step towards the emergence of the RNA world. However, it is likely that the prebiotic synthesis of ribonucleotides was accompanied by the simultaneous synthesis of arabinonucleotides, 2′-deoxyribonucleotides, and other variations on the canonical nucleotides. In order to understand how relatively homogeneous RNA could have emerged from such complex mixtures, we have examined the properties of arabinonucleotides and 2′-deoxyribonucleotides in nonenzymatic template-directed primer extension reactions. We show that nonenzymatic primer extension with activated arabinonucleotides is much less efficient than with activated ribonucleotides, and furthermore that once an arabinonucleotide is incorporated, continued primer extension is strongly inhibited. As previously shown, 2′-deoxyribonucleotides are also less efficiently incorporated in primer extension reactions, but the difference is more modest. Experiments with mixtures of nucleotides suggest that the coexistence of ribo- and arabino-nucleotides does not impede the copying of RNA templates. Moreover, chimeric oligoribonucleotides containing 2′-deoxy- or arabino-nucleotides are effective templates for RNA synthesis. We propose that the initial genetic polymers were random sequence chimeric oligonucleotides formed by untemplated polymerization, but that template copying chemistry favored RNA synthesis; multiple rounds of replication may have led to pools of oligomers composed mainly of RNA.

POPDC proteins and cardiac function

2019 ◽  
Vol 47 (5) ◽  
pp. 1393-1404 ◽  
Author(s):  
Thomas Brand
Keyword(s):  
Potential Role ◽  
Striated Muscle ◽  
Short Review ◽  
Effector Proteins ◽  
Muscle Disease ◽  
Disease Genes ◽  
Protein Protein Interaction ◽  
Interaction Partners ◽  
And Function

Abstract The Popeye domain-containing gene family encodes a novel class of cAMP effector proteins in striated muscle tissue. In this short review, we first introduce the protein family and discuss their structure and function with an emphasis on their role in cyclic AMP signalling. Another focus of this review is the recently discovered role of POPDC genes as striated muscle disease genes, which have been associated with cardiac arrhythmia and muscular dystrophy. The pathological phenotypes observed in patients will be compared with phenotypes present in null and knockin mutations in zebrafish and mouse. A number of protein–protein interaction partners have been discovered and the potential role of POPDC proteins to control the subcellular localization and function of these interacting proteins will be discussed. Finally, we outline several areas, where research is urgently needed.

Sign in / Sign up

Export Citation Format

Share Document