Non-Watson-Crick RNA synthesis suited to origin functions.
RNA
; 24(1): 90-97, 2018 01.
Article
em En
| MEDLINE
| ID: mdl-29042506
ABSTRACT
A templated RNA synthesis is characterized in which G5'pp5'G accelerates synthesis of A5'pp5'A from pA and chemically activated ImpA precursors. Similar acceleration is not observable in the presence of UppU, CppC, AppG, AppA, or pG alone. Thus, it seems likely that AppA is templated by GppG via a form or forms of GA base-pairing. AppA also appears, more slowly, via a previously known untemplated second-order chemical route. Such AppA synthesis requires only ordinary near-neutral solutions containing monovalent and divalent salts, and rates are only slightly sensitive to variation in pH. Templated synthesis rates are first order in pA, ImpA, and template GppG; thus third order overall. Therefore, this reaction resembles cross-templating of AppA on poly(U), but is notably slower and less sensitive to temperature. Viewing AppA as a coenzyme analog, GppG templating provides a simpler molecular route, termed para-templating, to encoded chemical functions. Para-templating can also arise from a single, localized nucleobase geosynthetic event which yields purines. It requires only a single backbone-forming chemistry. Thus it may have appeared earlier and served as evolutionary precursor for more complex forms of encoded genetic expression.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
RNA
Idioma:
En
Revista:
RNA
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Estados Unidos