Identification and expression analysis of 11 <i>MADS-box</i> genes in peach (<i>Prunus persica</i> var. <i>nectarina</i> ‘Luxing’)

MADS-box genes play a central role in the development of flowers in plants. In this study, 11 <i>PpMADS</i>s were isolated from ‘Luxing’ peach, and the expression levels were detected in different tissues and fruit development. Eleven <i>PpMADS</i>s, designated as <i>PpMADS13, 14, 18, 23, 24, 25, 32, 33, 34, 35</i>, and <i>39</i> were isolated. Phylogenetic analysis revealed that <i>PpMADS13, 14</i>, and <i>18</i> belonged to SVP, AGL15, and MIKC* group respectively; <i>PpMADS23, 24, 25</i>, and <i>39</i> were in the Mα group; <i>PpMADS32, 33, 34</i>, and <i>35</i> belonged to the Mγ group. Predictions from subcellular localization showed that 10 PpMADS were located in the nucleus. RT-PCR revealed that <i>PpMADS13</i> was expressed in stems, leaves, and during fruit development (70d); <i>PpMADS14</i> was expressed in sepals, stamens, petals, and during flower development; <i>PpMADS18</i> was expressed in roots, stems, leaves, sepals, ovaries, stamens, petals, and during flower and fruit development; all MADS-box genes (expect for <i>PpMADS33</i>) in the Mα and Mγ group were expressed in roots, stems, leaves, sepals, ovaries, stamens, petals, and during flower development; few genes were expressed during fruit development. These results indicated that <i>PpMADS</i> may play a crucial regulatory role in vegetative growth and development processes of flowers and fruits in peaches.