The transcriptional legacy of developmental stochasticity

AbstractGenetic variation, epigenetic regulation and major environmental stimuli are key contributors to phenotypic variation, but the influence of minor perturbations or “noise” has been difficult to assess in mammals. In this work, we uncover one major axis of random variation with a large and permanent influence: developmental stochasticity. By assaying the transcriptome of wild monozygotic quadruplets of the nine-banded armadillo, we find that persistent changes occur early in development, and these give rise to clear transcriptional signatures which uniquely characterize individuals relative to siblings. Comparing these results to human twins, we find the transcriptional signatures which define individuals exhibit conserved co-expression, suggesting a substantial fraction of phenotypic and disease discordance within mammals arises from developmental stochasticity.One sentence summaryLongitudinal gene expression in identical armadillo quadruplets reveals a major role for developmental stochasticity.

Download Full-text

Genetic and epigenetic regulation of phenotypic variation in invasive plants – linking research trends towards a unified framework

NeoBiota ◽

10.3897/neobiota.49.33723 ◽

2019 ◽

Vol 49 ◽

pp. 77-103 ◽

Cited By ~ 3

Author(s):

Achyut Kumar Banerjee ◽

Wuxia Guo ◽

Yelin Huang

Keyword(s):

Invasive Species ◽

Genetic Variation ◽

Invasive Plants ◽

Epigenetic Regulation ◽

Phenotypic Variation ◽

Molecular Mechanisms ◽

Invasive Plant ◽

Invasive Plant Species ◽

Unified Framework ◽

Introduced Range

Phenotypic variation in the introduced range of an invasive species can be modified by genetic variation, environmental conditions and their interaction, as well as stochastic events like genetic drift. Recent studies found that epigenetic modifications may also contribute to phenotypic variation being independent of genetic changes. Despite gaining profound ecological insights from empirical studies, understanding the relative contributions of these molecular mechanisms behind phenotypic variation has received little attention for invasive plant species in particular. This review therefore aimed at summarizing and synthesizing information on the genetic and epigenetic basis of phenotypic variation of alien invasive plants in the introduced range and their evolutionary consequences. Transgenerational inheritance of epigenetic modifications was highlighted focusing on its influence on microevolution of the invasive plant species. We presented a comprehensive account of epigenetic regulation of phenotypic variation and its role in plant invasion in the presence of reduced standing genetic variation, inbreeding depression and associated genomic events which have often been observed during introduction and range expansion of an invasive alien species. Finally, taking clues from the studies conducted so far, we proposed a unified framework of future experimental approaches to understand ecological and evolutionary aspects of phenotypic variation. This holistic approach, being aligned to the invasion process in particular (introduction-establishment-spread), was intended to understand the molecular mechanisms of phenotypic variation of an invasive species in its introduced range and to disentangle the effects of standing genetic variation and epigenetic regulation of phenotypic variation.

Download Full-text