GAIL L. WARING
Professor

B.A. 1968, San Francisco State College
M.A. 1969, San Francisco State College
Ph.D. 1974, University of Oregon
Postdoctoral Fellow, Indiana University

WLS 209
(414) 288-7518
email: gail.waring@marquette.edu

Regulation of Gene Expression and Extracellular Assembly Processes in Drosophila

The formation of functional three-dimensional architectures is a fundamental process that occurs in all cells and developing organisms. Understanding the molecular strategies and mechanisms that are used to ensure that supramolecular assemblies form in the right place, at the right time, and with the right shape will require an in vivo approach since spatial and temporal controls as well as the intricate multi-component environment found in vivo cannot be reproduced in vitro.  The Drosophila eggshell is a highly organized multi-layered structure that forms between the oocyte and overlaying follicle cells during the later stages of oogenesis.   The temporal resolution provided by Drosophila oogenesis, the spatial resolution provided by its large, well- defined structure, the diverse array of genetic tools available in Drosophila, and the large pool of genetically engineered eggshell mutants, make the Drosophila eggshell an excellent system for studying the assembly of a complex extracellular architecture in vivo. 

The Drosophila eggshell consists of three major proteinaceous layers: an oocyte proximal vitelline membrane, a crystalline innermost chorion layer, and an outer tripartite endochorion. In previous studies we showed that eggshell assembly involves post-depositional cleavage of several proteins, as well as regulated movement of specific proteins from the vitelline membrane to the outer eggshell layers. Recent studies have focused on two genes required for eggshell assembly and function, sV23 and dec-1. Using evolution and reverse genetics, we have identified regions and specific amino acids with the sV23 and dec-1 proteins that are critical for eggshell assembly. Current studies focus on how proteins are organized within the vitelline membrane layer, and how the molecular network(s) within this layer are disrupted by specific mutations in the sV23 and dec-1 proteins. This project provides students with an opportunity to use biochemical, molecular, and genetic tools to explore extracellular matrix assembly within a developmental context in a eukaryotic organism.

Selected References:

Spangenberg, D. K. and G.L. Waring.  2007.  A mutant dec-1 transgene induces dominant female sterility in Drosophila.  Genetics 177:1595-1608.

Manogaran, A. and G.L. Waring.  2004. The N-terminal prodomain of sV23 is essential for the assembly of a functional vitelline membrane network in Drosophila. Developmental Biology, 270:261-271.

Mauzy-Melitz, D. and G.L. Waring.  2003. fc177, a minor dec-1 proprotein, is necessary to prevent ectopic aggregation of the endochorion during eggshell assembly in Drosophila. Developmental Biology, 255:193-205.

Badciong, J.C, J.M. Otto and G.L. Waring.  2001. The functions of the multiproduct and rapidly evolving dec-1 eggshell gene are conserved between evolutionarily distant species of Drosophila. Genetics. 159:1089-102.

Trougakos, I.P., I.S. Papassideri, G.L. Waring and L.H. Margaritis. 2001. Differential sorting of constitutively co-secreted proteins in the ovarian follicle cells of Drosophila. European J of Cell Biology, 80: 271-84.

Nogueron, M.I., D. Mauzy-Melitz and G.L. Waring. 2000. Drosophila dec-1 eggshell proteins are differentially distributed via a multi-step extracellular processing and localization pathway. Developmental Biology, 225:459-70.

Presentations at recent meetings:

Wu, T. and Waring, G.L.  (2008) Highly conserved cysteines in the vitelline membrane domain of the sV23 eggshell protein are functionally distinct.  49th Annual Drosophila Research Conference

Current Graduate Student:

Tianyi Wu, Ph.D.

Former Graduate Students –Ph.D degrees earned: 

Joseph Fargnoli

Thomas Burke

Beverly Bauer

Robert Hawley

Smita Savant                        

Ellen Popodi,

Jeffrey M. Otto

M. Isabel Noguerón

Terri E. Pascucci,

James C. Badciong

Frank J. Fokta, Ph.D.           

Debra Mauzy-Melitz,

Anita Manogaran