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Full-Text Articles in Life Sciences
Purification And Characterization Of Hemolymph Juvenile Hormone Esterase From The Cricket, Gryllus Assimilis, Anthony J. Zera, Travis Sanger, Jeremiah Hanes, Lawrence G. Harshman
Purification And Characterization Of Hemolymph Juvenile Hormone Esterase From The Cricket, Gryllus Assimilis, Anthony J. Zera, Travis Sanger, Jeremiah Hanes, Lawrence G. Harshman
Anthony Zera Publications
Juvenile hormone esterase (JHE) from the serum of the cricket, Gryllus assimilis, was purified to homogeneity in a four-step procedure involving polyethylene glycol precipitation, hydrophobic interaction FPLC, and ion exchange FPLC. This procedure could be completed in 4 days and resulted in a greater than 900-fold purification with greater than 30% recovery. The purified enzyme exhibited a single band on a silver-stained SDS PAGE gel and had an apparent subunit molecular mass of 52 kDa. The native subunit molecular mass, determined by gel permeation FPLC, was 98 kDa, indicating that JHE from Gryllus assimilis is a dimer of two …
Evolutionary Endocrinology Of Juvenile Hormone Esterase: Functional Relationship With Wing Polymorphism In The Cricket, Gryllus Firmus, Anthony J. Zera, Yuan Huang
Evolutionary Endocrinology Of Juvenile Hormone Esterase: Functional Relationship With Wing Polymorphism In The Cricket, Gryllus Firmus, Anthony J. Zera, Yuan Huang
Anthony Zera Publications
The existence, nature, and physiological consequences of genetic variation for juvenile hormone esterase (JHE) activity was studied in the wing-polymorphic cricket, Gryllus firmus. Hemolymph (blood) JHE activity was sixfold lower in nascent short-winged (SW) females, relative to nascent long-winged (LW) females, during the last juvenile stadium (stage). Morph-associated genetic variation for JHE activity had two causes, variation in loci: (1) regulating whole-organism enzyme activity; and (2) controlling the degree to which JHE is secreted into the blood. Reduced JHE activity in nascent SW-selected individuals was associated with reduced in vivo juvenile hormone catabolism. This suggests that variation in JHE …
The Endocrine Genetics Of Wing Polymorphism In Gryllus: Critique Of Recent Studies And State Of The Art, Anthony J. Zera
The Endocrine Genetics Of Wing Polymorphism In Gryllus: Critique Of Recent Studies And State Of The Art, Anthony J. Zera
Anthony Zera Publications
In a series of papers, the most recent of which was published in Evolution, quantitative-genetic experiments were undertaken on reproductive and physiological correlates of wing polymorphism in the sand cricket, Gryllus firmus (Fairbairn 1994; Fairbairn and Yadlowski 1997; Roff et al. 1997). A goal of these studies was to determine the physiological causes underlying: (1) genetic variation for an ecologically important threshold trait (wing polymorphism); and (2) genetic correlations between wing morph and other reproductive and migratory features, such as fecundity and flight muscle histolysis. These authors concluded that genetic variation for the activity of the endocrine regulator, juvenile hormone …
Artificial Selection On Jhe Activity In Gryllus Assimilis: Nature Of Activity Differences Between Lines And Effect On Jh Binding And Metabolism, Anthony J. Zera, Jeffrey Sall, Robert Schwartz
Artificial Selection On Jhe Activity In Gryllus Assimilis: Nature Of Activity Differences Between Lines And Effect On Jh Binding And Metabolism, Anthony J. Zera, Jeffrey Sall, Robert Schwartz
Anthony Zera Publications
Genetic lines of the cricket Gryllus assimilis selected for elevated vs. decreased activity of hemolymph juvenile hormone esterase (JHE) exhibited a 6.8-fold difference in enzyme activity by the seventh generation of selection. This documents that hemolymph JHE activity has the capability for rapid evolutionary change. This is the only insect endocrine trait for which such data are currently available. The difference in hemolymph JHE activity between the lines was due, to an equivalent degree, to variation in whole-cricket enzyme activity and allocation of JHE activity to the hemolymph compartment. No differences in kinetic or thermostability characteristics were observed between JHEs …