Ros

Figure 5.6 Schematic representation of the theory by McElwee et al. which holds that a major contribution to the cellular aging process comes from lipophilic toxins generated by cellular activity and xenobiotics, which are biotransformed by phase I and phase II metabolism. ROS, reactive oxygen species CYPs, cytochrome P450s SDRs, short-chain dehydrogenase reductases UGTs, uridinediphosphate glucosyltransferases and uridinediphosphate glucuronosyltransferases GSTs, glutathione S-transferases...

Genomic approaches to lifehistory patterns an appraisal

Genomic analyses of life histories, as reviewed in this chapter, have revealed a number of molecular principles underlying regulation and determination of key life-history events. These can be summarized as follows. Environmental information (food, crowding, light, daylength, temperature) often modulates life-history traits and this is the basis of phenotypic plasticity. In animals, such information is typically processed by the nervous system, then translated into a hormonal signal, which acts...

Longevity and aging

Insulin Signalling Pathway

The nematode C. elegans has developed into a classical model for the study of aging. Most of this research is motivated by a possible connection with aging in humans, but the new insights accumulated over the last few years are of equal relevance to ecology and life-history theory. It also appears that the properties of the molecular machinery regulating aging are shared with Drosophila and are even conserved across the whole animal kingdom. The main reason why C. elegans became a model for...

Info

Distribution Whole Genome Duplication

Figure 3.25 Functional analysis of the Arabidopsis genes predicted from the genome sequence, showing the similarities between Arabidopsis functional gene categories and bacterial genomes E. coli and Synechocystis, a cyanobacterium and those of yeast, nematode, and fruit fly. The y axis indicates the fraction of Arabidopsis genes in a functional category showing a BLAST match with the respective reference genome. The right to use this figure provided courtesy of members of the Arabidopsis Genome...

A B C D E F G H

Figure 2.5 Example of results from a differential screening approach applied to clones from a subtracted library sexual versus asexual strains from the freshwater planarian G. tigrina . Clones arrayed on nylon membranes were selected randomly from the subtracted library top panels to study upregulation, and the reverse-subtracted library bottom panels to study downregulation. The dot-blots were then hybridized to labelled probes prepared from the subtracted left-hand panels and...

Stress and the ecological niche

Ecological Niche Graph

Even the most casual observer of natural systems will note that many species tend to occupy a characteristic place in nature. The idea is demonstrated most vividly by gradient studies, for example the distribution of plants on a salt marsh, where each species tends to be limited to a certain zone by a combination of soil texture, redox potential, salt, and lime. Ecologists have invented the concept of an ecological niche to organize their thoughts about the ways in which organisms fit into...

Saccharomyces Cerevisiae

Life Cycle Saccharomyces Cerevisiae

White rot, in fallen trees, on forest floor, degrades lignin Sources and Kellis et al. 2003, 2004 . Sources and Kellis et al. 2003, 2004 . or white rot fungus, which is found commonly on dead trees and wood fragments on the forest floor. To date, white rot fungus is the only basidomycete mushroom-forming fungus that has had its genome sequenced Martinez et al. 2004 . White rot owes its name to the fact that the fungus 'bleaches' wood by degrading the brown-coloured lignin, rendering the white...