Regulation of the maize HRGP gene expression by ethylene and wounding. mRNA accumulation and qualitative expression analysis of the promoter by microprojectile bombardment

Abstract

The expression of the maize gene coding for a hydroxyproline-rich glycoprotein (HRGP) has been studied by measuring the m R N A accumulation after wounding or ethylene treatment. RNA blot and in situ hybridization techniques have been used. The temporal and tissue-specific expression has been observed: the cells related to the vascular system show the more intense HRGP m R N A accumulation. Transcriptional constructions of the maize HRGP promoter have been tested on different maize tissues by microbombarding. A 582 bp promoter is able to direct the expression of the gus gene on calli and young leaves. Constructions having shorter promoter sequences lose this ability. The 582 bp construction retains the general specificity of expression observed for the HRGP gene.

Location of a cell-wall hydroxyproline-rich glycoprotein, cellulose and ?-1,3-glucans in apical and differentiated regions of maize mycorrhizal roots

“…Wounding, pathogenic fungi or fungal elicitors induce genes coding for HRGPs, and cause an accumulation of HRGP transcripts (Showalter et al 1985;Templeton et al 1990). In maize, too, the HRGP gene is induced by wounding and ethylene Tagu et al 1992). Our results do not allow us to distinguish between HRGP depostion as a result of mechanisms related to those acting during cell division or those related to defence reactions.…”

“…Maize HRGP has been shown to be accumulated in organs rich in dividing cells, in particular in the root meristem, but not in the cortex of differentiated roots, where it is induced during lateral root formation ). The gene can also be induced by wounding and ethylene Tagu et al 1992).…”

Interface between haustoria of parasitic members of the Scrophulariaceae and their hosts: A histochemical and immunocytochemical approach

“…The highlightening of the collapsed and crushed host cortical cells in all the three host-parasite interactions by the LM1 MAb gives evidence for a pronounced presence of HRGPs in this region. By cross-linking cell wall macromolecules, HRGPs are thought to be implicated in plant defense, providing a mechanical barrier to invasion by pathogens (Showalter et al 1985, Ludevid et al 1990, Tagu et al 1992, Showalter 1993). The pronounced labelling of host cell walls at the interface by the MAb LM1 can be interpreted in this direction.…”

Genetic, molecular and cellular approaches to the analysis of maize embryo development

“…The ZmHRGP protein was initially immunodetected in maize root tip cell walls of young maize seedlings . ZmHRGP gene expression was mainly associated to actively dividing tissues and involved in the response to wounding , ethylene (Tagu et al, 1992), symbiotic infection with Glomus versiforme (Balestrini et al, 1994(Balestrini et al, , 1997 and pathogens, being induced by ascorbic acid and reduced glutathione (Garcia-Muniz et al, 1998). During seed development ZmHRGP gene expression is found in the exocarp (Jose-Estanyol and Puigdomènech., 2000) but it is also expressed in the embryo (Jose-Estanyol and Puigdomènech, 1998a).…”

“…The high level of ZmHRGP gene expression in the silk has allowed to identify multiple bands by Northern analysis that have been explained as secondary structures of zmHRGP mRNA (Garcia-Muniz et al 1999). Functional promoter analysis revealed different regulatory elements in maize (Vallés et al 1991, Tagu et al 1992 and rice (Guo et al, 1994) HRGP promoter regions, the latter not being responsive to wounding. In the presence of the 3' untranslated region, the levels of GUS activity directed by the maize HRGP and 35S promoters could be modulated (Menossi et al, 2003).…”