However, the data we present here cannot distinguish between direct and indirect transcriptional targets of SEU and ANT regulation and thus our ability to define the transcriptional hierarchy of CMM development is limited at this time. Future analyses aimed to identify direct transcriptional targets of SEU and ANT regulation through chromatin-immunoprecipitation or glucocorticoid-inducible activities will help to identify the subset of candidates listed here that are directly regulated by SEU and ANT. These analyses will help to better delineate the levels of the transcriptional hierarchy required for CMM development and may illuminate the mechanistic basis for the synergistic genetic interaction between seu and ant mutants during CMM development. Synergistic genetic interactions are commonly observed in animal, plant and fungal systems and yet the mechanistic basis for the synergistic effect typically is poorly understood. Interestingly, ten of the 31 Approach II candidate genes have been previously identified by Gomez-Mena and colleagues as induced in response to the MADS domain-containing transcription factor AG. Based on our ATH1 data and follow-up qRT-PCR, the levels of AG transcript accumulation are not statistically different between the wild-type, seu, ant, or seu ant double mutant in the gynoecial Nutlin-3 inquirer samples. These data Life Science Reagents suggest that SEU and ANT do not alter the levels of AG accumulation in the CMM, but rather they may work in parallel to AG and/or might alter the ability of the AG protein to function. The SEU transcriptional adaptor is known to physically interact with dimers of MADS domain DNA-binding proteins during the specification of floral organ identity. We speculate that SEU may function in the developing gynoecium by mediating the action of MADS domain proteins and thus support the expression of a subset of the identified Approach II candidate genes. It is notable that both VDD and REM16 are direct targets of the MADS protein SEEDSTICK. Our in situ analyses together with the work of other groups indicates that at least 16 of the 31 Approach II candidate genes are expressed preferentially within the medial gynoecial domain with respect to their gynoecial expression. The exact timing and position of expression within the medial domain varies between the candidates. Yet many of these genes similarly display strong expression within the apical-most portion of the medial gynoecial domain. These expression patterns suggest that the medial apex might be functionally distinct from other portions of the gynoecium as early as stage 6. The common expression pattern of many of these candidates suggests that gene regulation events within the apical medial domain of the gynoecium may be critical for the subsequent initiation of ovule primordia from the medial ridge tissues. In this scenario the maintenance of a particular transcriptional or cellular state within the medial apex would be required to maintain the meristematic potential of the medial domain during elongation of the gyneocial tube. synthesis of auxin via the indole-3- pyruvic acid branch of the auxin biosynthesis pathway.