Tagged: cellulose





A diagram of the paper

ARP2/3 complex links cell wall assembly and auxin distribution

The protein complex ARP2/3 is responsible for nucleating actin, and its loss results in multiple defects in young seedlings of Arabidopsis thaliana. Sahi et al. show that plants lacking the ARP2/3 complex have defects associated with cell wall synthesis. Mature tissues of inflorescence stems contain less cellulose and more homogalacturonan, cell walls are thinner, and lignification is altered. Stems of mutant plants have reduced basipetal auxin transport and a changed auxin influx carrier (AUX1) expression pattern. Since cell wall composition and auxin transport are functionally connected, morphogenetic defects may be explained by ARP2/3 control of cell wall synthesis and/or auxin...

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Pollen tubes

Effects of sucrose depletion on pollen tube growth

Pollen tubes are rapidly growing, photosynthetically inactive cells that need high rates of energy to support growth. Energy can derive from internal and external storage sources. The lack of carbon sources can cause various problems during pollen tube growth, which in turn could affect the reproduction of plants. Parotta and colleagues analysed the effects of energy deficiency on the development of Nicotiana tabacum (Solanaceae) pollen tubes by replacing sucrose with glycerol in the growth medium. They focused on cell growth and related processes, such as metabolite composition and cell wall synthesis. The team found that the lack of sucrose affects...

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Guard cells around stomata

A fresh look at guard cell walls

Arguably, one of the best known ‘structure-function’ relationships in plant biology is the role played by cellulose microfibrils within the walls of the guard cells in stomatal opening. Stomata* are the controllable orifices found primarily within the epidermis of the above-ground organs of higher plants. When open they permit ready exchange of gases (e.g. CO2, O2) between the interior of the plant and the environment thereby facilitating photosynthesis, and aerobic respiration. However, when open, H2O – in the gaseous form of water vapour – can also leave the plant in the process known as transpiration. Where water in the soil...

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Functional approach to predicting root decomposition

Functional approach to predicting root decomposition

Much of plant biomass is in roots but we know much less about root properties that affect decomposition rates than we do about above-ground tissues. Aulen and Shipley measure decomposition rates of 17 species of trees and herbs using intact soil cores in the field and relate the differences to root chemical and morphological properties. They find that initial root traits account for 75 % of variation in interspecific decomposition rates, and may thus provide a relatively simple way of assessing root turnover.

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