Evolutionary conservation of mechanisms for neural regionalization, proliferation and interconnection in brain development

Abstract

Comparative studies of brain development in vertebrate and invertebrate model systems demonstrate remarkable similarities in expression and action of developmental control genes during embryonic patterning, neural proliferation and circuit formation in the brain. Thus, comparable sets of developmental control genes are involved in specifying the early brain primordium as well as in regionalized patterning along its anteroposterior and dorsoventral axes. Furthermore, similar cellular and molecular mechanisms underlie the formation and proliferation of neural stem cell-like progenitors that generate the neurons in the central nervous systems. Finally, neural identity and some complex circuit interconnections in specific brain domains appear to be comparable in vertebrates and invertebrates and may depend on similar developmental control genes.

Extension of cortical synaptic development distinguishes humans from chimpanzees and macaques

“…The large magnitude of this timing difference, as well as its association with neural development, a process generally known for its evolutionary conservation (Finlay and Darlington 1995;Reichert 2009), suggests an extraordinary change during the last few million years of human evolution.…”

Neural mechanisms underlying the evolvability of behaviour

“…In insects, major areas and pathways are recognizable across members of a taxon such as Diptera [19]. These brain regions are also recognizable across major taxa such as between insects and Crustacea [20] and possibly even across phyla [21][22][23]. This is not to say that major changes in organization have not occurred; certainly, there are important differences in structure that correspond to functional divergence in the visual system and mushroom body of insects [24][25][26].…”

Evo-Devo and Brain Scaling: Candidate Developmental Mechanisms for Variation and Constancy in Vertebrate Brain Evolution

“…Variations in the number of central nervous system segments [Bergquist and Källén, 1954;Gilland and Baker, 1993;Northcutt, 2001Northcutt, , 2002Puelles and Rubenstein, 2003], basic segmental structure [Northcutt, 2002;Urbach and Technau, 2008], and circuit organization are relatively rare [Medina and Reiner, 1995;Katz and Harris-Warrick, 1999;Reichert, 2009], as are changes in the complement of the small molecules which serve as neurotransmitters and neuromodulators [Venter et al, 1988;Medina and Reiner, 1995;Wong et al, 2011]. On the other hand, changes in the relative brain size or its parts [Stephan et al, 1981;Northcutt, 2002;Kaskan et al, 2005;Reep et al, 2007;Yopak et al, 2010], large morphological diversification of single neuronal types [Arendt, 2008], as well as changes in neurotransmitter receptor structure and distribution appear to occur commonly [Insel et al, 1991;Katz and Harris-Warrick, 1999;Goodson and Bass, 2001;Callier et al, 2003;Lim et al, 2004;Goodson, 2008].…”