The cell wall of kiwifruit pollen tubes is a target for chromium toxicity: alterations to morphology, callose pattern and arabinogalactan protein distribution.
Plant Biol (Stuttg)
; 11(2): 179-93, 2009 Mar.
Article
em En
| MEDLINE
| ID: mdl-19228325
ABSTRACT
Trivalent chromium has previously been found to effectively inhibit kiwifruit pollen tube emergence and elongation in vitro. In the present study, a photometric measure of increases in tube wall production during germination showed that 25 and 50 mum CrCl(3) treatment induced a substantial reduction in levels of polysaccharides in walls over those in controls. Moreover, chromium-treated kiwifruit pollen tubes had irregular and indented cell walls. Callose, the major tube wall polysaccharide, was deposited in an anomalous punctuate pattern. Arabinogalactan proteins (AGPs), which are integral in maintaining correct tube growth and shape in kiwifruit pollen, were found to be strongly altered in their distribution after CrCl(3) treatment compared to control tube walls. Transmission electron microscopy-immunogold analysis using four monoclonal antibodies (JIM8, JIM13, JIM14 and MAC207) revealed discontinuous AGP distribution within the treated tube walls. Such clearly discernable alterations in the molecular and morphological architecture of pollen tube walls may be detrimental in vivo for the male gametophyte to accomplish its vital role in the fertilisation process.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Parede Celular
/
Cromo
/
Actinidia
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Tubo Polínico
/
Glucanos
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Mucoproteínas
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article