STRESS ACTIVATION OF A BEAN HYDROXYPROLINE-RICH GLYCOPROTEIN PROMOTERIS SUPERIMPOSED ON A PATTERN OF TISSUE-SPECIFIC DEVELOPMENTAL EXPRESSION

The HRCP4.1 gene, which encodes a cell wall hydroxyprolinerich glycopr otein, was isolated from a genomic library of bean (Phaseolus vulgaris L.). Two transcripts, one induced by wounding and one by elicitation, were transcribed from the same initiation site. The gene encodes a po lypeptide of 580 amino acids with the amino terminal half consisting o f repeats of the sequence tidine-serine-(proline)(4)-(tyrosine)(3)-his tidine and the carboxyl-terminal half composed of repeats of the seque nce serine-(proline)(4)-valine-tyrosine-lysine. A 964-bp upstream prom oter fragment was translationally fused to the beta-glucuronidase repo rter gene (Escherichia coli uidA) and transferred into tobacco by Agro bacterium tumefaciens-mediated leaf disc transformation. Analysis of b eta-glucuronidase activity showed that wounding caused local activatio n of the HRCP4.1 promoter in the phloem. Infection by tobacco mosaic v irus was a less effective inducer than wounding. Stress induction was superimposed on tissue-specific developmental expression in stem nodes and root tips, suggesting that HRGP4.1 may have specific structural r oles in development as well as protective functions in defense. Deleti on analysis showed that control of tissue specificity and wound induci bility lies in a region between -94 and -251 relative to the transcrip tion start site and that activation by infection lies outside that reg ion.