Andrew C. Terranova

The biosynthesis of the male housefly accessory secretion and its fate in the mated female

Abstract Autoradiographic studies of ejaculatory ducts from male houseflies, Musca domestica , previously injected with either tritiated arginine, lysine, or histidine showed that only arginine and lysine were incorporated into the stored accessory secretion. Scintillation spectrophotometry indicated that the amount of [ 3 H] arginine incorporated into the duct correlated with the number of times the male had previously copulated. Cycloheximide and actinomycin D were effective in inhibiting the uptake of [ 3 H] arginine in the ejaculatory ducts of newly emerged males, but only cycloheximide was an effective inhibitor in older males that had mated repeatedly. Autoradiography and electron microscopy showed that during mating the accessory secretion was transferred to the vaginal pouches of the female and that within 10 min after mating began, it was penetrating the intimal lining of the pouches. Cytolysis of many of the cells of these pouches was correlated to the transfer of the secretion during mating. This transfer of the secretion apparently terminated about 40 min after copulation began, although mating usually continued for an additional 10 to 20 min. The amount of 3 H-labelled material in the haemolymph of the females increased until the completion of mating and then decreased about 60 per cent after 8 hr.

Electrophoresis of the male accessory secretion and its fate in the mated female

Polyacrylamide disk gel electrophoresis of homogenates of the ejaculatory ducts of male houseflies, Musca domestica, yielded 20 stainable protein fractions; 12 proteins (ranging from 650 to 4150 in molecular weight) could be definitely attributed to the ducts, and the remaining 8 were presumed by virtue of the relative mobilities to result from contamination with haemolymph. Studies of the incorporation of 14C-labelled amino acids into the ducts showed that relatively more arginine and asparagine were taken up followed, in order, by lysine, phenylalanine, methionine, glycine, cysteine, tyrosine, valine, threonine, leucine, isoleucine, histidine, and serine. Only trace amounts of proline, tryptophan, aspartic acid, alanine, glutamic acid, and glutamine were found. Since the components of the ejaculatory duct transferred to the female via copulation were selectively absorbed by the head, thorax, and abdomen of the female, we have support for the hypothesis of a multi-functional role of the male accessory secretion in the regulation of female physiology.

Diazo transparencies of polyacrylamide slab gels

Abstract A diazo print method is presented for reproducing most of the isozyme patterns obtained with electrophoresed or isoelectric-focused polyacrylamide slab gels. Gel reproductions can be made on the laboratory bench without expensive photographic equipment or darkroom facilities, and finished positive transparencies are produced in only a few minutes.

Soluble acid phosphatases from the posterior reproductive system of the female housefly, Musca domestica

Abstract When the kinetics of the acid phosphatase enzyme system from the posterior reproductive tract of the female housefly, Musca domestica , were studied, enzyme activity was zero order for 2 hr and was temperature-dependent. Orthophosphate release was linearily related to enzyme concentration, and pH optima between pH 3·3 to 3·7, 4·2 to 4·8, and 5·2 to 5·7 were observed. Magnesium and calcium ions were enzyme activators; arsenate, phosphate, fluoride, and hydroxymalonate ions were inhibitors. Sodium azide had little effect. The similarity of activity exhibited on the test substrates indicated that the soluble enzymes corresponded to the non-specific phosphomonoesterases. Disk electrophoresis showed that at least 6 proteins had acid phosphatase activity and were pH-dependent. Also, electrophoresis of extracts of the various structures of the reproductive tract showed that there was a tissue specificity in the distribution of the acid phosphatase isoenzymes.

A rotating temperature-controlled water bath for isozyme development in polyacrylamide slab gels☆☆☆

Abstract Plans are presented for an inexpensive heating bath which slowly rotates polyacrylamide or starch gels so that they are gently and continuously agitated in the dark. Rotation of the gels allows the use of significantly reduced amounts of biochemicals for isozyme development.