In AraBidopsis thaliana, the three MADS Box genes SEEDSTICK (STK) (AT4G09960) , SHATTERPROOF1 (SHP1) (AT3G58780) , and SHP2 (AT2G42830) redundantly regulate ovule development. STK is a MADS Box transcription factor expressed in the carpel and ovules. It plays a maternal role in fertilization and seed development.
