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Mariana F. Wolfner     (WEB PAGE) mfw5 @ cornell.edu 423 Biotech Bldg. (office); 421 Biotech Bldg. (lab)      607 254-4801   [edit] Faculty Department: Molecular Biology and Genetics Field: Genetics and Development Keywords: Cell and Molecular Neuroscience (23), Development (21), Drosophila (4), Genetics (9) One of two project areas in my lab is related to neuroscience. In this project we study molecules that modulate the reproductive capacity of mated female animals. We use Drosophila as a model for our studies, because of the genetic/genomic analyses it permits. In Drosophila, as in other animals with internal fertilization, males donate sperm and seminal fluid proteins to females during mating. In Drosophila females, seminal proteins (called ÏAcpsÓ for male ACcessory gland Proteins) stimulate egg production and ovulation, alter female mating behavior to decrease remating, aid in sperm storage, and affect the females' longevity. The ~80 Acps include peptide hormones (or their precursors), proteolysis regulators and other enzymes, protective peptides (e.g. antimicrobial peptides) and proteins (e.g. thioredoxin), and sperm- management proteins. We are identifying and characterizing the functions and targets of Acps, and the responses of females (at the molecular level) to these proteins. Our neuroscience-related work presumes that modulation of muscle contraction underlie some Acp effects such as ovulation, egg deposition, the movement of sperm into storage and their retention there. We tested whether mating or Acps affect vesicle release in the Drosophila female reproductive tract, by using a GFP-tagged vesicle protein, pro-ANF-EMD, that accumulates at nerve termini when expressed under the control of the elav promoter (fly line provided by D. Deitcher, Cornell NBB). When vesicles release pro-ANF-EMD, its fluorescence intensity drops. We used this system to assess vesicle release in the reproductive tracts of females that had mated to normal males or to males lacking Acps and/or sperm. We found that vesicle release is modulated in the reproductive tract after mating, and some of that modulation depends on Acps. Different regions of the reproductive tract respond independently and at different times. For example, 20 minutes after mating vesicle release is triggered at nerve termini in the lower reproductive tract, by the physical act of mating (not by Acps). Later, at the time of maximal ovulation and sperm storage, Acps inhibit vesicle release in the upper reproductive tract (sperm storage organs, oviducts). Our longterm aim is to identify the neuromodulators within these vesicles, and to correlate their release with Acp signaling (on the one hand) and the consequent response by the female (on the other hand).

Please report corrections, questions, comments, and problems to: Lori Miller (lmm8 AT cornell.edu)