Ecological annotation of genes and genomes through ecological genomics (original) (raw)

Bridging the lab-field divide? The 'eco' in ecological genomics

2013

The emerging field of ecological genomics promises to bring about a marriage between ecological and laboratory-based, genomic investigations. In this paper, I will reflect on this promise by exploring how ecology and genomics are integrated in the two approaches that currently dominate this field: the organism-centred approach, focusing on individual (model) organisms, and the metagenomic approach, concentrating on (the metagenome of) entire microbial communities composed of a variety of species. I will show that both approaches have already taken some important steps in bridging the gap between genomics and ecology. Since the introduction of next-generation sequencing methodology in 2007, the organism-centred approach does not need to stick to classical model organisms like Arabidopsis anymore. Instead, it is now able to apply genomic tools to ecologically interesting species (e.g. amphibians, reptiles, birds) as well. The metagenomic approach has been able to give ecology a more prominent place in its investigations, in another way. Contrary to classical microbiology (the field from which it originates), it does not study microbial communities under controlled laboratory settings, but under nature's own conditions. However, in the marriage between genomics and ecology, genomics still appears to be the dominant partner, especially in the case of the organism-centred approach that continues to study the new ecological models in artificial lab environments. Moreover, the organism-centred and metagenomic approaches employ a gene-centred perspective in understanding critical ecological interactions, thus strengthening a reductionist rather than a holistic (systems-oriented) approach.

Extending Genomics to Natural Communities and Ecosystems

Science, 2008

An important step in the integration of ecology and genomics is the progression from molecular studies of relatively simple model systems to complex field systems. The recent availability of sequenced genomes from key plants is leading to a new understanding of the molecular drivers of community composition and ecosystem processes. As genome sequences accumulate for species that form intimate associations in nature, a detailed view may emerge as to how these associations cause changes among species at the nucleotide level. This advance could dramatically alter views about the structure and evolution of communities and ecosystems.

Ecological genomics: making the leap from model systems in the lab to native populations in the field

Frontiers in Ecology and The Environment, 2007

Recent reviews have emphasized the need to incorporate genomics into ecological field studies to further understand how species respond to changing environmental conditions. Genomic tools, such as cDNA (complementary DNA) microarrays, allow for the simultaneous analysis of gene expression of thousands of genes from all or part of an organism's genome (the transcription profile), thereby revealing the genetic mechanisms that underlie species' responses to environmental change. However, despite their potential, two major limitations have hindered the incorporation of microarrays and other genomic tools into field studies: (1) the limited availability of microarrays for ecologically relevant, non-model species and limited financial resources for developing new microarrays; and (2) concern that high sensitivity of gene expression to even subtle alterations in environmental conditions will hinder detection of relevant changes in field measures of transcription profiles. Here, we show that with cross-species hybridizations of microarrays developed for a closely related model organism, an appropriate experimental design, and sufficient replication, transcriptional profiling can successfully be incorporated into field studies. In this way, relevant changes in gene expression with changing environmental conditions can be detected. Ecological genomics SE Travers et al. 20 www.frontiersinecology.org

Ecological Genomics and Epidemiology

European Journal of Plant Pathology, 2006

The huge amount of genomic data now becoming available offers both opportunities and challenges for epidemiologists. In this “preview” of likely developments as the field of ecological genomics evolves and merges with epidemiology, we discuss how epidemiology can use new information about genetic sequences and gene expression to form predictions about epidemic features and outcomes and for understanding host resistance and pathogen evolution. DNA sequencing is now complete for some hosts and several pathogens. Microarrays make it possible to measure gene expression simultaneously for thousands of genes. These tools will contribute to plant disease epidemiology by providing information about which resistance or pathogenicity genes are present in individuals and populations, what genes other than those directly involved in resistance and virulence are important in epidemics, the role of the phenotypic status of hosts and pathogens, and the role of the status of the environmental metagenome. Conversely, models of group dynamics supplied by population biology and ecology may be used to interpret gene expression within individual organisms and in populations of organisms. Genomic tools have great potential for improving understanding of resistance gene evolution and the durability of resistance. For example, DNA sequence analysis can be used to evaluate whether an arms race model of co-evolution is supported. Finally, new genomic tools will make it possible to consider the landscape ecology of epidemics in terms of host resistance both as determined by genotype and as expressed in host phenotypes in response to the biotic and abiotic environment. Host phenotype mixtures can be modeled and evaluated, with epidemiological predictions based on phenotypic characteristics such as physiological age and status in terms of induced systemic resistance or systemic acquired resistance.

Linking molecular insight and ecological research

Trends in Ecology & Evolution, 2002

Significant environmental challenges, including the genetic and physiological effects of environmental pollutants, the rapid spread of diseases and invasive species, the release of transgenic organisms and global climate change, affect our daily lives and the sustainability of ecosystems. Managing these environmental problems will require new approaches that span the biology of genes, organisms, populations, communities and ecosystems. In parallel with these practical concerns is the basic need to study gene functions in their natural context. The Arabidopsis 2010 project, for example, seeks to understand the functions of all 25 000 Arabidopsis genes within a decade but, to do so, we must also understand the role of the environment in determining gene function. A new priority is evident -understanding the interplay of molecular mechanisms with organismal and ecosystem biology. Combining genomic and ecological research perspectives will answer crucial unresolved questions, but will require significant new multidisciplinary resources, infrastructure and training.

Genes to ecosystems: exploring the frontiers of ecology with one of the smallest biological units

New Phytologist, 2011

Genes and their expression levels in individual species can structure whole communities and affect ecosystem processes. Although much has been written about community and ecosystem phenotypes with a few model systems, such as poplar and goldenrod, here we explore the potential application of a community genetics approach with systems involving invasive species, climate change and pollution. We argue that community genetics can reveal patterns and processes that otherwise might remain undetected. To further facilitate the community genetics or genes-to-ecosystem concept, we propose four community genetics postulates that allow for the conclusion of a causal relationship between the gene and its effect on the ecosystem. Although most current studies do not satisfy these criteria completely, several come close and, in so doing, begin to provide a genetic-based understanding of communities and ecosystems, as well as a sound basis for conservation and management practices.