Unstable anthocyanin pigmentation in Streptocarpus sect. Saintpaulia (African violet) is due to transcriptional selectivity of a single MYB gene.

Saintpaulia (African violet) pigmentation is notoriously unstable and sometimes forms white stripes, particularly following passage through tissue culture. White-striped petals were thought to be due to periclinal chimeras, but we confirmed that white stripes result from epigenetic regulation rather than periclinal chimeras based on the flower color traits of plants obtained from tissue culture. Gene expression in several plant lines, anthocyanin quantification, bisulfite sequencing, and methylation analyses were used to demonstrate the presence of a single MYB gene responsible for pigment variation.

Palladium-Catalyzed Cyanothiolation of Internal Alkynes Using Organic Disulfides and tert-Butyl Isocyanide.

Despite the availability of selective synthetic approaches to multifunctionalized substituted olefins, the cyanothiolation of internal alkynes has been much less explored. Herein, we show that nonactivated internal alkynes can be successfully cyanothiolated with diaryl disulfides and tert-butyl isocyanide in the presence of a Pd catalyst (e.g.