Seven MADS-box Genes in Apple are Expressed in Different Parts of the Fruit

Abstract

<jats:p>To study the role of MADS-box genes in developing apples (<jats:italic>Malus</jats:italic> ×<jats:italic>domestica</jats:italic> Borkh<jats:italic>.</jats:italic>), clones corresponding to seven different genes, <jats:italic>MdMADS5</jats:italic> to <jats:italic>MdMADS11</jats:italic>, were isolated from a 2-day-old apple cDNA library. Through DNA sequence comparison, six genes were classified into the <jats:italic>APETALA1</jats:italic> (<jats:italic>AP1</jats:italic>) group and one gene, <jats:italic>MdMADS10,</jats:italic> into the <jats:italic>AGAMOUS</jats:italic> (<jats:italic>AG</jats:italic>) group. Six of the genes, <jats:italic>MdMADS5</jats:italic> to <jats:italic>MdMADS10,</jats:italic> were found to be preferentially expressed in fruit following pollination. These genes also showed differential expression patterns in core, cortex and skin of young fruit. For instance, <jats:italic>MdMADS5</jats:italic>, which is highly homologous to <jats:italic>AP1</jats:italic>, showed preferential expression in the cortex and skin tissues while <jats:italic>MdMADS10</jats:italic>, which is highly homologous to <jats:italic>AGL11</jats:italic>, showed exclusive expression in the core tissues. The gene <jats:italic>MdMADS11</jats:italic> showed a similar expression level and pattern in flowers, fruit at several early developmental stages, and for different fruit tissues. The range of expression patterns suggests that the genes play different roles in apple development.</jats:p>

Developmentally regulated expression of two MADS-box genes, MdMADS3 and MdMADS4 , in the morphogenesis of flower buds and fruits in apple

“…1A,B) reveals that both MdMADS3 and MdMADS4 show high sequence relatedness to various MADS proteins in the AGL2 subfamily (Theiûen et al 1996). The MdMADS3 protein shares 99% overall identity with MdMADS7, which was previously isolated from the apple cultivar Granny Smith (Yao et al 1999); only one substitution is present at the 177 th amino acid located in the C-region. The MdMADS4 protein shares the highest amino acid identity (63%) with CMB1 (accession No.…”

“…The deduced amino acid sequence of MdMADS3 diered from that of MdMADS7 in only the one position located in the C-region. It has been reported by RNA blot analysis that MdMADS7 is highly expressed in apple fruit (Yao et al 1999). However, we have experienced cross-hybridization of the MdMADS3 probe with other MADS-box genes in apple even though the highly conserved MADS-box The asterisks and the numbers on the left are as represented in A.…”

“…Recently, several MADS-box cDNA clones have been isolated from the¯owers of fruit trees, including eucalypt and apple (Kyozuka et al 1997;Sung and An 1997;Southerton et al 1998;Sung et al 1999;Yao et al 1999). Analyses of the nucleotide sequences and expression patterns revealed that the fruit-tree genes share similarities with other plant MADS-box genes that function during¯oral development (Kyozuka et al 1997;Southerton et al 1998;Sung et al 1999).…”

“…Analyses of the nucleotide sequences and expression patterns revealed that the fruit-tree genes share similarities with other plant MADS-box genes that function during¯oral development (Kyozuka et al 1997;Southerton et al 1998;Sung et al 1999). It was reported that some of the clones from eucalypt and apple were expressed in developing receptacles and fruits (Sung and An 1997;Southerton et al 1998;Yao et al 1999). However, the spatial and temporal expression patterns of the MADS-box genes during fruit development have not been studied.…”

Development of microsatellite markers in peach [Prunus persica (L.) Batsch] and their use in genetic diversity analysis in peach and sweet cherry (Prunus avium L.)

“…They form a superfamily whose members share a highly conserved domain of 56 amino acids. In plants, they play key roles in plant development, as reported for apple (Yao et al 1999), and in the development of specific organs, like floral whorls (Coen and Meyerowitz 1991).…”