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Journal ArticleDOI

Relationship Between Growth Rate and Ribonucleic Acid Concentration in Some Invertebrates

01 Mar 1970-Wsq: Women's Studies Quarterly (NRC Research Press Ottawa, Canada)-Vol. 27, Iss: 3, pp 606-609
TL;DR: A positive relationship between growth rate and ribonucleic acid concentration is shown for 24 species, mostly arthropods and microorganisms, and it is suggested that such a relationship might exist also for mammals.
Abstract: A positive relationship between growth rate and ribonucleic acid concentration is shown for 24 species, mostly arthropods and microorganisms. It is suggested that such a relationship might exist also for mammals.
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Journal ArticleDOI
01 Jul 2004-Ecology
TL;DR: This work has developed a quantitative theory for how metabolic rate varies with body size and temperature, and predicts how metabolic theory predicts how this rate controls ecological processes at all levels of organization from individuals to the biosphere.
Abstract: Metabolism provides a basis for using first principles of physics, chemistry, and biology to link the biology of individual organisms to the ecology of populations, communities, and ecosystems. Metabolic rate, the rate at which organisms take up, transform, and expend energy and materials, is the most fundamental biological rate. We have developed a quantitative theory for how metabolic rate varies with body size and temperature. Metabolic theory predicts how metabolic rate, by setting the rates of resource uptake from the environment and resource allocation to survival, growth, and reproduction, controls ecological processes at all levels of organization from individuals to the biosphere. Examples include: (1) life history attributes, including devel- opment rate, mortality rate, age at maturity, life span, and population growth rate; (2) population interactions, including carrying capacity, rates of competition and predation, and patterns of species diversity; and (3) ecosystem processes, including rates of biomass production and respiration and patterns of trophic dynamics. Data compiled from the ecological literature strongly support the theoretical predictions. Even- tually, metabolic theory may provide a conceptual foundation for much of ecology, just as genetic theory provides a foundation for much of evolutionary biology.

6,017 citations

Journal ArticleDOI
TL;DR: It is hypothesized that the continuous generation of variation in the rDNA may also play a role in how species interactions develop in ecosystems under different conditions of energy input and nutrient supply.
Abstract: Ecological stoichiometry is the study of the balance of multiple chemical elements in ecological interactions. This paper reviews recent findings in this area and seeks to broaden the stoichiometric concept for use in evolutionary studies, in integrating ecological dynamics with cellular and genetic mechanisms, and in developing a unified means for studying diverse organisms in diverse habitats. This broader approach would then be considered “biological stoichiometry”. Evidence supporting a hypothesised connection between the C:N:P stoichiometry of an organism and its growth rate (the “growth rate hypothesis”) is reviewed. Various data indicate that rapidly growing organisms commonly have low biomass C:P and N:P ratios. Evidence is then discussed suggesting that low C:P and N:P ratios in rapidly growing organisms reflect increased allocation to P-rich ribosomal RNA (rRNA), as rapid protein synthesis by ribosomes is required to support fast growth. Indeed, diverse organisms (bacteria, copepods, fishes, others) exhibit increased RNA levels when growing actively. This implies that evolutionary processes that generate, directly or indirectly, variation in a major life history trait (specific growth rate) have consequences for ecological dynamics due to their effects on organismal elemental composition. Genetic mechanisms by which organisms generate high RNA, high growth rate phenotypes are discussed next, focusing on the structure and organisation of the ribosomal RNA genes (the “rDNA”). In particular, published studies of a variety of taxa suggest an association between growth rate and variation in the length and content of the intergenic spacer (IGS) region of the rDNA tandem repeat unit. In particular, under conditions favouring increased growth or yield, the number of repeat units (“enhancers”) increases (and the IGS increases in length), and transcription rates of rRNA increase. In addition, there is evidence in the literature that increased numbers of copies of rDNA genes are associated with increased growth and production. Thus, a combination of genetic mechanisms may be responsible for establishing the growth potential, and thus the RNA allocation and C:N:P composition, of an organism. Furthermore, various processes, during both sexual and asexual reproduction, can generate variation in the rDNA to provide the raw material for selection and to generate ecologically significant variation in C:N:P stoichiometry. This leads us to hypothesize that the continuous generation of such variation may also play a role in how species interactions develop in ecosystems under different conditions of energy input and nutrient supply.

1,037 citations

Journal ArticleDOI
TL;DR: The close relationship between P and RNA contents indicates that ribosomes themselves represent a biogeochemically significant repository of P in ecosystems and that allocation of P to ribosome generation is a central process in biological production in ecological systems.
Abstract: Biological stoichiometry provides a mechanistic theory linking cellular and biochemical features of co-evolving biota with constraints imposed by ecosystem energy and nutrient inputs. Thus, understanding variation in biomass carbon : nitrogen : phosphorus (C : N : P) stoichiometry is a major priority for integrative biology. Among various factors affecting organism stoichiometry, differences in C : P and N : P stoichiometry have been hypothesized to reflect organismal P-content because of altered allocation to P-rich ribosomal RNA at different growth rates (the growth rate hypothesis, GRH). We tested the GRH using data for microbes, insects, and crustaceans and we show here that growth, RNA content, and biomass P content are tightly coupled across species, during ontogeny, and under physiological P limitation. We also show, however, that this coupling is relaxed when P is not limiting for growth. The close relationship between P and RNA contents indicates that ribosomes themselves represent a biogeochemically significant repository of P in ecosystems and that allocation of P to ribosome generation is a central process in biological production in ecological systems.

779 citations


Cites background from "Relationship Between Growth Rate an..."

  • ...For example, a close coupling of growth and RNA content was reported in a study that included other species of microbes and insects (Sutcliffe 1970) and similar arguments for a close association among growth, RNA content and P content in P-limited phytoplankton have recently been made (Geider & La…...

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Journal ArticleDOI
TL;DR: The dynamic indices reviewed are based on production estimates, and hence reflect physiological changes over specified time intervals, and only net growth efficiency is recommended for use in bivalve aquaculture, and it is applicable to all life stages.

438 citations


Cites background from "Relationship Between Growth Rate an..."

  • ...It has been demonstrated in bivalves and other aquatic organisms that the RNA level, and in particular the RNA : DNA ratio, is directly related to ongoing tissue growth (Sutcliffe, 1965, 1970; Bulow, 1970; Haines, 1973; Holland and Hannant, 1973)....

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Journal ArticleDOI
TL;DR: Water temperature and larval RNA-DNA ratio explained 92% of the variability in growth rate of laboratory-reared larvae and suggest that short-term growth under favorable conditions may be considerably higher than expected from long-term indicators.
Abstract: Data on water temperature, RNA-DNA ratio, and growth of eight species of temperate marine fish larvae reared in the laboratory were fit to the equation: $$G_{pi} = 0.93{\text{ }}\operatorname{T} + 4.75{\text{ RNA - DNA}} - 18.18$$ where Gpi is the protein growth rate in % d-1 and T is the water temperature. Water temperature and larval RNA-DNA ratio explained 92% of the variability in growth rate of laboratory-reared larvae. The model is useful over the entire range of feeding levels (starvation to excess), temperatures (2° to 20°C) and fish species studied. Estimates of recent growth of larval cod, haddock, and sand lance caught at sea based on water temperature and RNA-DNA ratio ranged from negative to 26% d-1. These data demonstrate the importance of food availability in larval fish mortality and suggest that short-term growth under favorable conditions may be considerably higher than expected from long-term indicators. RNA-DNA ratio analysis offers new possibilities for understanding larval growth and mortality, and their relation to environmental variability.

407 citations

References
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Journal ArticleDOI
TL;DR: In this article, the variation of DNA, RNA and growth with age has been studied in Tribolium confusum, Duval in relation to different morphological changes, and it was shown that RNA synthesis precedes protein synthesis (growth) and follows DNA synthesis.

30 citations