| Baby Boom (BBM) is an AP2/ERF transcription factor expressed in early androgenesis and zygotic embryogenesis that causes spontaneous somatic embryogenesis when ectopically expressed. The objective of this research was to determine whether BBM expression would be sufficient to induce embryogenesis which may increase the percent of embryogenic microspores in B. napus and the induction of embryogenic microspores in Arabidopsis. To test this, transgenic B. napus and Arabidopsis with BBM RNAi constructs and transgenic Arabidopsis with BBM and BBM-GFP fusions driven by an inducible promoter were produced. RNAi interference of BBM did not produce an embryo-lethal phenotype in either Arabidopsis or B. napus. T-DNA interference of Arabidopsis BBM confirmed these results. The inducible expression of BBM was shown to promote embryogenesis in cotyledons, hypocotyls and meristem tissue of young seedlings but was not sufficient to induce embryogenesis in roots, petioles or leaves. These results suggest that BBM is sufficient to induce somatic embryogenesis in some tissues, but not all, and is not required for zygotic embryogenesis. |
