Synthesis of a pheromone precursor in the male noctuid moth, Mamestra configurata

Identification of Multiple Loci Associated with Social Parasitism in Honeybees

In colonies of the honeybee Apis mellifera, the queen is usually the only reproductive female, which produces new females (queens and workers) by laying fertilized eggs. However, in one subspecies of A. mellifera, known as the Cape bee (A. m. capensis), worker bees reproduce asexually by thelytoky, an abnormal form of meiosis where two daughter nucleii fuse to form single diploid eggs, which develop into females without being fertilized. The Cape bee also exhibits a suite of phenotypes that facilitate social parasitism whereby workers lay such eggs in foreign colonies so their offspring can exploit their resources. The genetic basis of this switch to social parasitism in the Cape bee is unknown. To address this, we compared genome variation in a sample of Cape bees with other African populations. We find genetic divergence between these populations to be very low on average but identify several regions of the genome with extreme differentiation. The regions are strongly enriched for signals of selection in Cape bees, indicating that increased levels of positive selection have produced the unique set of derived phenotypic traits in this subspecies. Genetic variation within these regions allows unambiguous genetic identification of Cape bees and likely underlies the genetic basis of social parasitism. The candidate loci include genes involved in ecdysteroid signaling and juvenile hormone and dopamine biosynthesis, which may regulate worker ovary activation and others whose products localize at the centrosome and are implicated in chromosomal segregation during meiosis. Functional analysis of these loci will yield insights into the processes of reproduction and chemical signaling in both parasitic and non-parasitic populations and advance understanding of the process of normal and atypical meiosis.

Saponins from the flower buds of Buddleja officinalis

Five new saponins, mimengosides C-G (1-5), were isolated from the flower buds of Buddleja officinalis along with five known compounds, namely, songaroside A, acteoside, phenylethyl 2-glucoside, echinacoside, and phenylethyl alcohol 8-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside. The structures of 1-5 were elucidated using spectroscopic and chemical methods, and these compounds were evaluated for their inhibitory effects against HL-60 leukemia cells.