Developmental and tissue-specific expression of JIP-23, a jasmonate-inducible protein of barley.
Developmental expression of a 23 kDa jasmonate-induced protein (JIP-23) of barley leaves (Hordeum vulgare cv. Salome) was studied by measuring the time-dependent accumulation of transcript and protein during germination. Tissue-specific expression of JIP-23 was analyzed immunocytochemically and by in situ hybridizations, respectively. During seed germination JIP-23 mRNA was found to accumulate transiently with a maximum at 32 h, whereas the protein was steadily detectable after the onset of expression. The occurrence of new isoforms of JIP-23 during germination in comparison to jasmonate-treated leaves suggests, that the JIP-23 gene family of barley is able to express different subsets of isoforms dependent on the developmental stage. JIP-23 and its transcript were found mainly in the scutellum, the scutellar nodule and in lower parts of the primary leaf of 6 days old seedings. All these tissues exhibited high levels of endogenous jasmonates. In situ hybridization revealed specific accumulation of JIP-23 mRNA in companion cells of the phloem in the nodule plate of the scutellum. In accordance with that, JIP-23 was detected immunocytochemically in phloem cells of the root as well as of the scutellar nodule and in parenchymatic cells of the scutellum. The cell type-specific occurrence of JIP-23 was restricted to cells, which are known to be highly stressed osmotically by active solute transport. This observation suggests, that the expression of this protein might be a response to osmotic stress during development.
Hause
B
B
Institute of Plant Biochemistry Halle, Halle/Saale, Germany.
Demus
U
U
Teichmann
C
C
Parthier
B
B
Wasternack
C
C
D003517:Cyclopentanes / Q000378:metabolism*; D015870:Gene Expression; D001467:Hordeum / Q000378:metabolism*; D054883:Oxylipins; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger; D018749:RNA, Plant; D012639:Seeds
D003517:Cyclopentanes; D054883:Oxylipins; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; C011006:jasmonic acid