Plant Molecular Biology 36: 909–915, 1998.
1998 Kluwer Academic Publishers. Printed in Belgium.
Apple messenger RNAs related to bacterial lignostilbene dioxygenase and
plant SAUR genes are preferentially expressed in ﬂowers
, Richard Kettmann
, Abdelilah Arredouani
, Jean-Franc¸ois Hecquet
e Universitaire des Sciences Agronomiques, Unit
eculaire et Physiologie animale
author for correspondence), and
Centre de Recherches Agronomiques, Station des Cultures Fruiti
eres, 5030 Gembloux, Belgium
Received 18 April 1997; accepted in revised form 20 November 1997
Key words: apple, differential display, lignostilbene dioxygenase, Malus, SAUR genes
In an attempt to use a differential display procedure to identify organ-speciﬁc genes in apple, cDNA fragments of
two transcripts preferentially expressed in ﬂowers were isolated and corresponding full-length cDNA inserts were
subsequently obtained. One of these clones, Md-FS1, belongs to the SAUR gene family, originally identiﬁed as a
set of auxin-induciblegenes in soybean. The second one, Md-FS2, encodes a polypeptide with sequence similarities
to bacterial lignostilbene-
-dioxygenase isozymes, which are thought to be involved in lignin biodegradation.
Northern blot analysis conﬁrmed that both genes are preferentially expressed in ﬂoral organs at full bloom, while
being expressed at lower or undetectable levels in vegetative organs (leaves, shoots or roots) as well as in immature,
green and unopened blossoms. Furthermore, Md-FS1 transcripts also appeared to accumulate in vegetative tissues
after auxin treatment of micropropagated apple shoots.
Most processes taking place in living organisms are
regulated, at least partly, through modiﬁcations in the
expression of speciﬁc genes. Therefore, understanding
the biological systems often relies on comparisons of
gene expression in different cells or at different times.
RNA ﬁngerprinting by arbitrarily primed PCR has been
proposed as a convenient method to compare messen-
ger RNA populations in different biological samples
and, subsequently, to clone transcripts that are differ-
entially expressed under various circumstances .
Since the initial report of a ‘differential display’ pro-
cedure by Liang and Pardee in 1992 , several
improved or modiﬁed methods have been described
[12, 18]. In plants, these techniques have been suc-
cessfully used to clone transcripts whose expression
is altered during fruit ripening, induced by chemical
The nucleotidesequence data reported will appear in theEMBL,
GenBank and DDBJ Nucleotide Sequence Databases under the
accession numbers Z93765 (Md-FS2) and Z93766 (Md-FS1).
treatments or differentially expressed along cell cycle
[1, 4, 21]. A project aimed at understanding woody
plant development has been undertaken in our labor-
atory. In the course of this project, genes playing key
rolesin plant developmentpathwayshavebeen isolated
from apple (Malus domestica [L.] Borkh.)tree[19, 20].
As a preliminary step to validate the use of differential
display procedures as tools to dissect molecular events
associated with woody plant development, the method
described by Sokolov and Prockop  was used to
clone transcripts which are preferentially expressed in
Identiﬁcation of mRNAs with enhanced expression in
The PCR-based RNA ﬁngerprinting method described
by Sokolov and Prockop  was used to compare
messenger populations derived from apple leaves and
ﬂowers. Total RNA was extracted from apple leaves
and ﬂowers (at full bloom) and polyadenylated tran-
Gr.: 201001269, PIPS Nr. 157540 BIO2KAP
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