Rapid Changes in Plant Genomes

Henikoff, Steven

doi:10.1105/tpc.105.038000

Cited by 15 publications

(15 citation statements)

References 19 publications

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“…An example in plants is the observation that environmental effects of different mineral balances on flax branching morphology (and tobacco) can last for 10 to 12 generations (Durrant, 1962(Durrant, , 1971Hill, 1965). In response to stress, both the plant phenotype and, astonishingly, the genotype seem to have changed (Ries et al, 2000;Kovalchuk et al, 2003;Henikoff, 2005). Even specific mutations seem capable of repair (Lolle et al, 2005).…”

Section: Communication and Control Within Systemsmentioning

confidence: 99%

A Brief History of Systems Biology

Trewavas

2006

Plant Cell

147

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''Every object that biology studies is a system of systems. '' Francois Jacob (1974).A system is a network of mutually dependent and thus interconnected components comprising a unified whole. Every system exhibits emergent behavior, a unique property possessed only by the whole system and not shared to any great degree by the individual components on their own. Systems biology is currently undergoing enormous expansion, but there seems little awareness of either the history of systems biology or the behavior of systems that make them exciting to study. The aim of this article is to expand on both themes. Original references that pioneered changes in perception of systems structure and behavior are indicated, and a few modern developments are briefly referenced to indicate progress. The essay focuses on systems biology prior to the age of genomics and large-scale biology, with the intent of giving modern systems biologists a sense of the extensive foundations of the field.The understanding of systems has had enormous impact on what are loosely regarded as human sciences, including economics, sociology, psychology, and medicine. Systems biology has generated revolutions in ecology, population biology, and evolutionary studies and is slowly making inroads into biochemistry, development, genetics, and whole-plant biology. But it is only very recently that molecular biology has adopted a systems approach. The enormous growth in genomics now makes this possible. Currently, this is an age of systems, and systems structure and behavior should form the core of all student biology courses. All biological systems are effectively systems within systems, as indicated by Jacob above. Understanding the complexity of biological systems represents the greatest intellectual and experimental challenge yet faced by any biologist.This article is structured as follows. First, consideration is given to how systems approaches developed and what, in turn, they replaced or refined. The hierarchical structure of systems is then explained and the possibility of a definition examined. Since systems are composed of interlinked components, the connections and communication within the various parts of the hierarchy are outlined, and the article finishes with some of the less-understood, and sometimes counterintuitive, aspects of systems behavior.

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Section: Communication and Control Within Systemsmentioning

confidence: 99%

A Brief History of Systems Biology

Trewavas

2006

Plant Cell

147

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“…Lolle et al (2005) suggested that RNAs synthesized by the parent may be stored in plants of subsequent generations that do not carry the corresponding genomic information and that these RNAs may be used as a template to restore the genomic information carried by the previous generation. Four alternative hypotheses have been proposed to account for this nonMendelian behavior: two of them are also based on template-directed gene conversion (Chaudhury 2005;Ray 2005), the third one appeals to a process of mutation accumulation followed by selection (Comai and Cartwright 2005;Henikoff 2005), and the fourth one involves chimerism (Krishnaswamy and Peterson 2007). However, Peng et al (2006) reported that hth mutant shows a tendency toward outcrossing and recover a normal genetic behavior when grown in isolation.…”

mentioning

confidence: 99%

Outcrossing as an Explanation of the Apparent Unconventional Genetic Behavior ofArabidopsis thaliana hthMutants

Mercier¹,

Jolivet²,

Vignard³

et al. 2008

Genetics

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The reappearance of HTH alleles in the offspring of homozygous Arabidopsis hth mutants is not consistent with classical Mendelian genetics. It has been suggested that stored RNA may be used to restore genetic information. However, Peng et al. reported that hth mutants tend to display outcrossing and suggested that outcrossing might provide an alternative explanation for the apparent genetic instability. We have confirmed and extended these results, corroborating that the apparent non-Mendelian behavior of hth mutants can be explained by their susceptibility to outcrossing.

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“…Aromatic glucosinolates are abundant in Arabidopsis seeds and flowers (Wittstock and Halkier, 2002;Brown et al, 2003), and a block in their metabolism could lead to toxicity and mutagenicity (Musk et al, 1995;Kassie et al, 1999;Kassie and Knasmuller, 2000;Canistro et al, 2004) and to genomic instability (Henikoff, 2005). The delayed and progressive onset of reversion could arise from suppressor mutations that ameliorate the toxic effect.…”

mentioning

confidence: 99%