Developmental plasticity

About: Developmental plasticity is a research topic. Over the lifetime, 1721 publications have been published within this topic receiving 103438 citations.

Experience-dependent expression of NPAS4 regulates plasticity in adult visual cortex

Abstract: There is evidence that developmental-like plasticity can be reactivated in the adult visual cortex. Although activity-dependent transcription factors underlying the process of plasticity reactivation are currently unknown, recent studies point towards NPAS4 as a candidate gene for the occurrence of plasticity in the adult visual system. Here, we addressed whether NPAS4 is involved in the reinstatement of plasticity by using the monocular deprivation protocol and long-term fluoxetine treatment as a pharmacological strategy that restores plasticity in adulthood. A combination of molecular assays for gene expression and epigenetic analysis, gene delivery by lentiviral infection, shRNA interference and electrophysiology as a functional read-out, revealed a previously unknown role for the transcription factor NPAS4 in the regulation of adult visual cortical plasticity. We found that NPAS4 overexpression restores ocular dominance plasticity in adult naive animals whereas NPAS4 down-regulation prevents the plastic outcome caused by fluoxetine in adulthood. Our findings lead the way to the identification of novel therapeutic targets for pathological conditions where reorganization of neuronal networks would be beneficial in adult life.

Developmental plasticity and the evolution of animal complex life cycles.

Abstract: Metazoan life cycles can be complex in different ways. A number of diverse phenotypes and reproductive events can sequentially occur along the cycle, and at certain stages a variety of developmenta...

Ontogenetic phenotypic plasticity during the reproductive phase in Arabidopsis thaliana (Brassicaceae).

Abstract: While phenotypic plasticity has been the focus of much research and debate in the recent ecological and evolutionary literature, the developmental nature of the phenomenon has been mostly overlooked. A developmental perspective must ultimately be an integral part of our understanding of how organisms cope with heterogeneous environments. In this paper I use the rapid cycling Arabidopsis thaliana to address the following questions concerning developmental plasticity. (1) Are there genetic and/or environmental differences in parameters describing ontogenetic trajectories? (2) Is ontogenetic variation produced by differences in genotypes and/or environments for two crucial traits of the reproductive phase of the life cycle, stem elongation and flower production? (3) Is there ontogenetic variability for the correlation between the two characters? I found genetic variation, plasticity, and variation for plasticity affecting at least some of the growth parameters, indicating potential for evolution via heterochronic shifts in ontogenetic trajectories. Within-population differences among families are determined before the onset of the reproductive phase, while among-population variation is the result of divergence during the reproductive phase of the ontogeny. Finally, the ontogenetic profiles of character correlations are very distinct between the ecologically meaningful categories of early- and late-flowering "ecotypes" in this species, and show susceptibility to environmental change.

Emergence and development of personality over the ontogeny of fish in absence of environmental stress factors

Abstract: Animals typically display among-individual differences in behavior that are consistent over time (i.e., personality). These differences are often triggered by variable individual responses to environmental stress factors experienced during life, such as competition for resources and risk of predation. While the causes underlying animal personality are considered to be an issue of prime importance, it is still unknown whether personality emerges and develops over ontogeny if the main sources of behavioral differentiation are absent. Here, we tested whether personality emerged and was strengthened during the lifetime of Eastern mosquitofish (Gambusia holbrooki), once intraspecific competition and risk of predation were completely removed and genetic and maternal differences minimized. We found that individual differences in behavior were overall repeatable over ontogeny (i.e., personality was manifested). Personality was, however, not detectable in juvenile individuals but emerged during and after their sexual maturation. The emergence of personality was triggered by the decline in behavioral plasticity of individuals over ontogeny, while differences in behavior among individuals did not vary with age. Our results suggest that animal personality might be inevitable and emerge in fish under laboratory-controlled conditions even in absence of extrinsic factors that typically lead to behavioral differentiation. The decline of behavioral plasticity over lifetime might be a relevant mechanism for the development of personality in animals. Increasing evidence suggests that animals have personality, that is, individuals consistently differ in behavior among each other (e.g., bold and shy or social and non-social individuals). Personality differences among animals should be, by definition, consistent over time and often caused by environmental challenges experienced early in life. In this study, we observed that personality differences were not present at juvenile age in social fish but emerged later in their life, despite the fact that environmental challenges (i.e., predation risk and competition for space, food, and mates) were absent. Personality differences strengthened over lifetime, resulting from declines in individual behavioral plasticity. Our results suggest that the decline in behavioral plasticity with age may represent a relevant mechanism for behavioral differentiation in animals, in agreement with evidences from the human literature on age-related loss in behavioral plasticity.