Expression of genes for a defensin and a proteinase inhibitor in specific areas of the shoot apex and the developing flower in tomato

Abstract

Two genes that are highly expressed in the tomato shoot apex have been cloned by differential hybridization. One of the deduced polypeptides (AT1) shows significant similarities to class II proteinase inhibitors, while the other (AT2) displays similarities to defensins. Transcripts of both genes are also detectable in the developing flower and are present only in minor amounts in other tissues tested. In situ hybridization analysis revealed that both genes are expressed in non-overlapping subsets of cells in the shoot apex, as well as in the developing flower. The potential use of these genes as markers for certain cell types and the possible biological function of the encoded proteins are discussed.

Identification of four Arabidopsis genes encoding hydroxycinnamate glucosyltransferases

“…As the corresponding nucleotide sequences retrieved from the databases reveal no introns, the Arabidopsis genes encoding the proteins BAB00006, D71419, E71419 and F71419 were amplified by polymerase chain reaction (PCR) with genomic Arabidopsis DNA as template. Genomic DNA was isolated according to Brandstädter et al [9] from rosette leaves of 5‐week‐old Arabidopsis plants ( Arabidopsis thaliana Heynh. ecotype Columbia) grown in the green house.…”

A defensin from tomato with dual function in defense and development

“…This defensin, here referred to as DEF1 (Supplemental Fig. S1B), is expressed in the outermost layers of leaf primordia and floral organs (Brandstadter et al 1996). We report herein functional analysis of the closely related DEF2 gene by altering its expression in transgenic tomato plants.…”

Antimicrobial skin peptides and proteins

“…There is ample evidence, that in plants, which do not contain any adaptive immune system, mainly antimicrobial peptides and proteins (AMPs) such as defensins and thionins represent the effector molecules (reviewed in [7]). These are often produced in the uppermost, environment-exposed layers of various plant organs [8], suggesting that these molecules may play a role as effector of the epithelial defense system to protect surfaces from infection. Apart from plants, invertebrate epithelia produce AMPs, as demonstrated in Drosophila melanogaster, where contact with microbes produces local induction of AMPs [9].…”