Cristin-prosjekt-ID: 351867
Sist endret: 14. januar 2015 16:56

Cristin-prosjekt-ID: 351867
Sist endret: 14. januar 2015 16:56
Prosjekt

196468/V40 - Genome size, cell size and growth; searching for casual links

prosjektleder

Dag Olav Hessen
ved Institutt for biovitenskap (tidl. IMBV) ved Universitetet i Oslo

prosjekteier / koordinerende forskningsansvarlig enhet

  • Centre for Ecological and Evolutionary Synthesis ved Universitetet i Oslo

Tidsramme

Avsluttet
Start: 1. januar 2010 Slutt: 30. november 2013

Beskrivelse Beskrivelse

Tittel

196468/V40 - Genome size, cell size and growth; searching for casual links

Sammendrag

We here aim both at exploring the causal links between growth rate, genome size and cell size and the evolutionary drivers for reduced genome size. There are likely several routes to genome size variability within and across taxa. Here, we are mainly interested in the observation that meiosis and cell division often is negatively correlated with genome size across plant and animal taxa. Since genome size and cell size also are tightly coupled, both cell and genome size should also show a strong negative correlation with developmental time. We hypothesize that this could be related to a phosphorus allocation from DNA to RNA under P-deficiency. A crucial question is thus the evolutionary drivers for reduced genome size in organisms, and how this actually is solved by the organisms.We will study both the role of polyploidy and genome downsizing after polyploidization, and the role of non-coding elements (transposons, repetitive units) in the context of genome streamlining. Yet we will address the aspect of genome streamlining on a broad scale, we will specifically study the material costs of producing nucleic acids, and how this may have relevance for the allocation of resources between DNA and RNA. A larger genome may result in higher investment into nucleic acids since the majority of the eukaryotic genomic DNA, including non-codingregions, may be transcribed. Our focus is on whether there are in fact energy and material costs that could select against large genomes. Such costs can be inferred from: (i) the existence of purely mechanical constraints related to faster and more efficient eplication and metabolic activity in smaller genomes and cells; and (ii) the tight coupling of rapid growth and cellular rRNA copy numbers, meaning that high somatic N and P contents may represent a tradeoff between material resources allocated to DNA vs. RNA. The project will be based both on meta-analysis of existing data and byexperiments with a range of organisms.

Vitenskapelig sammendrag

We here aim both at exploring the causal links between growth rate, genome size and cell size and the evolutionary drivers for reduced genome size. There are likely several routes to genome size variability within and across taxa. Here, we are mainly interested in the observation that meiosis and cell division often is negatively correlated with genome size across plant and animal taxa. Since genome size and cell size also are tightly coupled, both cell and genome size should also show a strong negative correlation with developmental time. We hypothesize that this could be related to a phosphorus allocation from DNA to RNA under P-deficiency. A crucial question is thus the evolutionary drivers for reduced genome size in organisms, and how this actually is solved by the organisms.We will study both the role of polyploidy and genome downsizing after polyploidization, and the role of non-coding elements (transposons, repetitive units) in the context of genome streamlining. Yet we will address the aspect of genome streamlining on a broad scale, we will specifically study the material costs of producing nucleic acids, and how this may have relevance for the allocation of resources between DNA and RNA. A larger genome may result in higher investment into nucleic acids since the majority of the eukaryotic genomic DNA, including non-codingregions, may be transcribed. Our focus is on whether there are in fact energy and material costs that could select against large genomes. Such costs can be inferred from: (i) the existence of purely mechanical constraints related to faster and more efficient eplication and metabolic activity in smaller genomes and cells; and (ii) the tight coupling of rapid growth and cellular rRNA copy numbers, meaning that high somatic N and P contents may represent a tradeoff between material resources allocated to DNA vs. RNA. The project will be based both on meta-analysis of existing data and byexperiments with a range of organisms.

prosjektdeltakere

prosjektleder
Aktiv cristin-person

Dag Olav Hessen

  • Tilknyttet:
    Prosjektleder
    ved Institutt for biovitenskap (tidl. IMBV) ved Universitetet i Oslo
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