Gene activation without histone acetylation in Drosophila melanogaster

Chromosomal puffing, generally believed to represent gene activation in Drosophila, was induced in the presence of radioactively labeled acetate. There is no preferential uptake of these labeled molecules in regions of gene activation. It is concluded that the acetylation of histones does not play a general role in the regulation of RNA synthesis in Drosophila melanogaster.     

The pathway of infection of Autographa californica nuclear polyhedrosis virus in an insect host

An immunohistochemical study was conducted to detect the temporal infection sequence of Autographa californica M nuclear polyhedrosis virus in Trichoplusia ni larvae. Staining patterns indicated that the initial infection occurred in the midgut, simultaneously in columnar epithelial and regenerative cells, but that subsequently this tissue recovered. A major envelope glycoprotein stained in a polar fashion when it was expressed in columnar epithelial cells, but not when expressed in other cells types. Systemic infection was mediated by free virus for some tissues whereas infected hemocytes appeared to spread virus to other tissues by an unknown mechanism. A cell to cell spread within several tissues was detected. These results have important implications for baculoviruses engineered for improving their pesticide potential.     

A mammalian thioglycosidase

A thioglycosidase capable of catalyzing the hydrolysis of 6-purine beta-d-glucothiopyranoside and other thioglycosides has been found in a number of mammalian tissues (including tumors) as well as in almond emulsin. The substrate specificity of mammalian thioglycosidase involves both the aglycone and the glycosyl moieties.