Developmental plasticity

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

Whisker-Related Axonal Patterns and Plasticity of Layer 2/3 Neurons in the Mouse Barrel Cortex

Abstract: Elucidating neuronal circuits and their plasticity in the cerebral cortex is one of the important questions in neuroscience research. Here we report novel axonal trajectories and their plasticity in the mouse somatosensory barrel cortex. We selectively visualized layer 2/3 neurons using in utero electroporation and examined the axonal trajectories of layer 2/3 neurons. We found that the axons of layer 2/3 neurons preferentially run in the septal regions of layer 4 and named this axonal pattern "barrel nets." The intensity of green fluorescent protein in the septal regions was markedly higher compared with that in barrel hollows. Focal in utero electroporation revealed that the axons in barrel nets were indeed derived from layer 2/3 neurons in the barrel cortex. During development, barrel nets became visible at postnatal day 10, which was well after the initial appearance of barrels. When whisker follicles were cauterized within 3 d after birth, the whisker-related pattern of barrel nets was altered, suggesting that cauterization of whisker follicles results in developmental plasticity of barrel nets. Our results uncover the novel axonal trajectories of layer 2/3 neurons with whisker-related patterns and their developmental plasticity in the mouse somatosensory cortex. Barrel nets should be useful for investigating the pattern formation and axonal reorganization of intracortical neuronal circuits.

Modulation of motor function and cortical plasticity in health and disease.

Abstract: Basic science studies demonstrated mechanisms of plasticity and metaplasticity. More recent human studies identified some of these mechanisms as operating in multiple areas of human cognition, such as learning and memory, and in functional recovery from lesions in the CNS, as in stroke. One of the goals of neurorehabilitation is the translation of these principles into rational strategies to promote recovery of function. Understanding the mechanisms and functional role of human plasticity could lead to the development of therapeutic options in situations in which there is virtually no treatment alternative, as in chronic stroke. We review some of the work performed to better understand the substrates and mechanisms underlying cortical plasticity and discuss some experimental approaches to enhance cortical plasticity and recovery of function, like cortical stimulation.

In a variable thermal environment selection favors greater plasticity of cell membranes in drosophila melanogaster

Abstract: Theory predicts that developmental plasticity, the capacity to change phenotypic trajectory during development, should evolve when the environment varies sufficiently among generations, owing to temporal (e.g., seasonal) variation or to migration among environments. We characterized the levels of cellular plasticity during development in populations of Drosophila melanogaster experimentally evolved for over three years in either constant or temporally variable thermal environments. We used two measures of the lipid composition of cell membranes as indices of physiological plasticity (a.k.a. acclimation): (1) change in the ratio of phosphatidylethanolamine (PE) to phosphatidylcholine (PC) and (2) change in lipid saturation (number of double bonds) in cool (16°C) relative to warm (25°C) developmental conditions. Flies evolved under variable environments had a greater capacity to acclimate the PE/PC ratio compared to flies evolved in constant environments, supporting the prediction that environments with high among-generation variance favor greater developmental plasticity. Our results are consistent with the selective advantage of a more environmentally sensitive allele that may have associated costs in constant environments.

Geographic variation in thermal plasticity of life history and wing pattern in Bicyclus anynana

Abstract: Temperature is one of the main environmental cues regulating seasonal plasticity in insects. Global climate change may lead to a change in the predictive value of temperature for sea- sonal conditions, potentially resulting in a mismatch of phenotypic form and environment. The afrotropical butterfly Bicyclus anynana shows striking seasonal plasticity for wing patterns and life history traits. This polyphenism is an adaptation to contrasting patterns of rainfall over wet and dry seasons, and is mainly determined by temperature. To investigate the extent of local adaptation of the developmental plasticity response to regional climate, we compared the thermal reaction norms for several life history traits and wing pattern of 2 distant populations from regions with different tem- perature-rainfall associations. We found little to no population differentiation for the life history traits, while wing pattern showed substantially more geographic variation. Broad-sense heritabilities and cross-environment correlations for wing pattern and 2 life history traits indicated a potential for adaptation of the plasticity response of these traits. Our results indicate that thermal plasticity of wing pattern can be population-specific; thus climate change may lead to a mismatch of wing pattern to seasonal environment. Traits that can be further modified by acclimation during the butterfly's adult life span (starvation resistance, resting metabolic rate and egg size) showed no geographic differen- tiation for their developmental plasticity. This indicates that for these traits, adult acclimation plays an important role in coping with local climate.

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.