C. Reinbothe et al., INDUCTION BY METHYL JASMONATE OF EMBRYOGENESIS-RELATED PROTEINS AND MESSENGER-RNAS IN NICOTIANA-PLUMBAGINIFOLIA, PLANT SCI, 104(1), 1994, pp. 59-70
Upon treatment with jasmonic acid methyl ester (methyl jasmonate, JaMe
) detached leaf segments of in vitro-regenerated plants of Nicotiana p
lumbaginifolia accumulate novel abundant proteins and mRNAs. Among the
m are late embryogenesis abundant (Lea) transcripts, which appear in a
temporally defined manner during somatic embryogenesis and normally d
o not occur in mature plant organs such as leaves or roots. To pursue
this observation, the induction by methyl jasmonate of embryogenesis-r
elated proteins and mRNAs in leaf and root tissues was investigated by
comparing the two-dimensional patterns of in vivo- and in vitro-trans
lated polypeptides. We found a selective reinduction by methyl jasmona
te of several embryo-specific proteins and mRNAs, whose expression is
associated with the formation of early and mature globular stages. Som
e of the jasmonate-induced embryo-specific proteins were also expresse
d in leaves, but not in roots, in response to abscisic acid (ABA) or o
smotic stress (sorbitol) treatment, suggesting their role in osmoprote
ction of leaf and embryo tissues as discussed for LEA proteins. Wester
n blot analyses with polyclonal antibodies raised against jasmonate-in
duced proteins (JIPs) of M(r) 23 000 from barley highlighted the tissu
e-specific reappearance of a group of closely related, evolutionarily
conserved embryo-specific proteins in N. plumbaginfolia leaves after J
aMe, ABA and sorbitol treatment. Actin and tubulin, for which the tran
script contents were estimated, increased in amount in the course of s
omatic embryogenesis, but did not change in abundance under the variou
s conditions of treatment. Our results imply a specific role of JaMe i
n controlling gene expression during somatic embryogenesis in N. plumb
aginifolia.