"Multiple S Gene Family Members Including Natural Antisense Transcripts Are Differentially Expressed during Development of Maize Flowers".
Rejane Ansaldi, Annie Chaboud 1, and Christian Dumas
From the Reproduction et Developpement des Plantes,
UMR 5667 CNRS-INRA-ENSL-UCBLyon1,
Ecole Normale Superieure de Lyon, 46 Alle d'Italie,
69634 Lyon Cedex 07, France
1 A member of the CNRS, to whom correspondence
should be addressed.
Tel: 33-4-72-72-86-04; Fax: 33-4-72-72-86-00;
E-mail: Annie.Chaboud@ens-lyon.fr
Within the large Brassica S gene family, SLG (S locus
glycoprotein) and SRK (S locus receptor kinase) participate to the
control of pollen-stigma self-incompatibility. In the self-compatible species
maize, S gene family members are predominantly expressed in vegetative
organs but are also expressed to a lesser extent in the stigma (silk).
To determine if the expression of any S gene family members correlates
with female receptivity, we analyzed their
expression in developing maize silks. We show that a large family
of maize S transcripts is expressed in developing silks. Surprisingly,
we isolated a cDNA complementary to a large portion of the antisense strand
of the maize receptor kinase S domain. Rapid amplification of cDNA
ends (RACE)-polymerase chain reaction, RNase protection, and Northern hybridization
with single-stranded riboprobes confirmed that natural antisense S transcripts
exist in leaves and seedling shoots and in all sexual tissues tested except
mature pollen. These natural antisense S transcripts co-exist with
several less abundant sense S transcripts. The accumulation of sense
and antisense S transcripts is differentially regulated during pollen
and silk development. Thus, these results support a role for S
gene family members in sexual tissue development and/or compatible
pollination and reveal a new level of complexity in the regulation and
function of the S gene family in maize.
The nucleotide sequences reported in this paper have been submitted to the GenBankTM/EMBL Data Bank with accession numbers AJ001485 and AJ001486.
"Oncogenes as Molecular Targets within Active Chromatin".