The pre-Mendelian, pre-Darwinian world: shifting relations between genetic and epigenetic mechanisms in early multicellular evolution.
J Biosci
;
2005 Feb; 30(1): 75-85
Artículo
en Inglés
| IMSEAR
| ID: sea-110823
ABSTRACT
The reliable dependence of many features of contemporary organisms on changes in gene content and activity is tied to the processes of Mendelian inheritance and Darwinian evolution. With regard to morphological characters, however, Mendelian inheritance is the exception rather than the rule, and neo-Darwinian mechanisms in any case do not account for the origination (as opposed to the inherited variation) of such characters. It is proposed, therefore, that multicellular organisms passed through a pre-Mendelian, pre-Darwinian phase, whereby cells, genes and gene products constituted complex systems with context-dependent, self-organizing morphogenetic capabilities. An example is provided of a plausible 'core' mechanism for the development of the vertebrate limb that is both inherently pattern forming and morphogenetically plastic. It is suggested that most complex multicellular structures originated from such systems. The notion that genes are privileged determinants of biological characters can only be sustained by neglecting questions of evolutionary origination and the evolution of developmental mechanisms.
Texto completo:
Disponible
Índice:
IMSEAR (Asia Sudoriental)
Asunto principal:
Regulación del Desarrollo de la Expresión Génica
/
Epigénesis Genética
/
Evolución Biológica
/
Extremidades
/
Animales
/
Morfogénesis
Idioma:
Inglés
Revista:
J Biosci
Año:
2005
Tipo del documento:
Artículo
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