Abstract Detail

Development and Structure

HD-AGP genes evolve rapidly and have roles in both reproductive and vascular development.

Histidine-domain arabinogalactan proteins (HD-AGPs) are extracellular glycoproteins that are highly expressed in pistil transmitting tissue and have been shown to promote pollen tube growth. AGP31 from Arabidopsis thaliana and TTS protein from Nicotiana are the best known members of this subfamily of arabinogalactan proteins. AGP31 is expressed in vascular tissue, and we have shown that TTS proteins are likewise expressed in vascular tissue in seedlings and leaves. Here, we used RT-qPCR and immunoblot analysis to examine the tissue-specific patterns of HD-AGP expression in the Solanaceae, and the regulation of the gene by abiotic and biotic stress. There are multiple tissue-specific glycoforms of the protein in Petunia and Nicotiana, and wounding triggers rapid deglycosylation of the high molecular mass isoforms. Methyl jasmonate and wounding both induce down-regulation of the gene. Etiolation and gibberellin treatment are associated with upregulation. The role of HD-AGPs in controlling vascular development is discussed.

1 - Western Washington University, Biology, Biology 516 High Street, Bellingham, WA, USA, WA, 98225, United States

Keywords:
gene expression
HD-AGP gene
vascular tissues
Gene evolution.

Presentation Type: Oral Paper
Number: DS5003
Abstract ID:1042
Candidate for Awards:None