of authors. Some of them find it unacceptable (Miller, Orgel, 1974; Orgel,
1987) while others point out the advantages of RNA molecules in their
metabolism and reproduction due to catalytic and autocatalytic properties
(Pace, Marsh, 1985; Zaug, Cech, 1986; Cech, 1987) that have been
foreseen by Woese (1967, 1968), Crick (1968), Orgel (1968), Sulston, Orgel
(1971). This has given grounds to Alberts (1986), Lazcano (1986) and Gilbert
(1986) to assume that there has never existed a prebiotic translation
synthesis of proteins and their reproduction and metabolism have been
dependent on the catalytic abilities of RNA molecules. Gilbert has forwarded
the \u201cRNA World\u201d as a possibility.
On the basis of a large number of studies \u2014 the proving of the central
role of the different RNA molecules in protein biosynthesis (Crick, 1968,
and others) which has led to the postulation that this process can be carried
out in the absence of DNA but is impossible without RNA (Spirin, 1986), the
existence of biological replicative systems such as the ones in the viroids
(Diener, 1982) and viruses (Reanney, 1982) that are using single or two\u0002stranded RNA molecules, the enzyme reduction role of ribonucleotides in
the synthesis of the deoxyribonucleotides (Sprengel, Follmann, 1981;
Lammers, Follmann, 1983) \u2014 a large number of authors have
independently expressed their view that RNA has preceded DNA as
genetic material and has played a great role in the biological processes at
the early stages of cell evolution (Lazcano, 1986, 1998).
These facts have led to the alteration of the postulated Central
dogma in biology established after 1953 with the Watson and Crick model
of DNA \u2014 DNA \u2192 RNA \u2192 protein into DNA RNA \u2192 protein. A two\u0002way arrow has been placed.
Despite the great achievements of biology the opinion of many authors
(Alberts et al., 1986; Or\u00f3 et al., 1990 and others), which is shared by the
author of the book, is that it is still quite unclear how exactly protein
biosynthesis takes place. This is especially true for the initial stages of the
existence of living systems when they did not have at their disposal the
complex mechanisms of synthesis and reproduction that have emerged later
and have established themselves in the evolutionary process at the cell and
organism level. This problem will be treated again in Chapter 2, Section 2. 7
(Proteins).
Since by now there is no clear and convincing scheme about the ways
and mechanisms by which the abiotic formation of the monomers was
effectuated through the \u201clucky combination\u201d of the atoms and their conversion
into polymers as well as there are no data about the exact timing of the
emergence of replication and translation in the biological systems, the problem
of the origin of life remains still unclear. Most justly Or\u00f3 et al. (1990) conceive
the origins of replication and translation as \u201ctwo major unsolved problems\u201d.
According to the authors these mechanisms are of crucial importance to the<\/p>\n","protected":false},"excerpt":{"rendered":"
of authors. Some of them find it unacceptable (Miller, Orgel, 1974; Orgel,1987) while others point out the advantages of RNA molecules in theirmetabolism and reproduction due to catalytic and autocatalytic properties(Pace, Marsh, 1985; Zaug, Cech, 1986; Cech, 1987) that have beenforeseen by Woese (1967, 1968), Crick (1968), Orgel (1968), Sulston, Orgel(1971). This has given grounds […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[6],"tags":[],"class_list":["post-379","post","type-post","status-publish","format-standard","hentry","category-book"],"_links":{"self":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts\/379","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=379"}],"version-history":[{"count":2,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts\/379\/revisions"}],"predecessor-version":[{"id":1072,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts\/379\/revisions\/1072"}],"wp:attachment":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=379"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=379"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=379"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}