A role for cappuccino and chickadee in regulation of vesicle transport during Drosophila development

Persistent Link:
http://hdl.handle.net/10150/193754
Title:
A role for cappuccino and chickadee in regulation of vesicle transport during Drosophila development
Author:
Balasundaram, Sujatha
Issue Date:
2006
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Establishment of polarity is a critical process that occurs early during development. In Drosophila melanogaster, axis determination occurs by localization of determinants during oogenesis. Mutations in cappuccino (capu) lead to defects in polarity establishment of both the anterior/posterior (A/P) and dorsal/ventral (D/V) axes during oogenesis. In the oocytes laid by capu mutant females, determinants that define these axes are either mislocalized or are absent. Several lines of evidence suggest that the regulation of cytoskeleton by the gene product encoded by capu is involved in Drosophila oogenesis.Capu, a member of the formin family of proteins, known to be regulators of actin dynamics, interacts both genetically and physically with chickadee (chic) which encodes the actin binding protein Profilin. I show here that mutations in both capu and chic lead to defects in the endocytic uptake of yolk into developing oocytes. I show that mutations in these loci lead to accumulation of abnormally large yolk granules and that this is a post internalization defect in the oocyte of capu and chic females. I also present evidence which indicates that an interaction with capu is necessary for chic regulation of yolk granule biogenesis.This is the first evidence for a formin subfamily of formin proteins to have a role in endocytosis. While this new function identified for the actin associated proteins Capu and Profilin indicates that regulation of actin cytoskeleton plays a role in endocytosis during oogenesis, the mechanism of this regulation and possible actin independent roles played by Capu and Profilin in this process are yet to be determined.Like capu, mutations in spire (spir) also show defects in A/P and D/V axes during oogenesis. Spir is an actin binding protein and like capu, mutations in spir shows defects in cytoskeletal architecture and suggests that capu and spire alter microtubule distribution in the oocyte during oogenesis.To identify molecular partners of capu and spir and their roles during oogenesis, I performed a genome-wide deficiency screen to identify regions of the genome that interact with these genes. I identified regions in the genome that showed interaction with capu and spir. While I was able to narrow down the region of interaction to a smaller cytological interval, gaps in the deficiency coverage and lack of mutants in those regions prevented me from identifying interacting loci in those regions.
Type:
text; Electronic Dissertation
Keywords:
Formin; cappuccino; spire; chickadee; endocytosis; yolk
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Molecular & Cellular Biology; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Ramaswami, Mani
Committee Chair:
Ramaswami, Mani

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleA role for cappuccino and chickadee in regulation of vesicle transport during Drosophila developmenten_US
dc.creatorBalasundaram, Sujathaen_US
dc.contributor.authorBalasundaram, Sujathaen_US
dc.date.issued2006en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractEstablishment of polarity is a critical process that occurs early during development. In Drosophila melanogaster, axis determination occurs by localization of determinants during oogenesis. Mutations in cappuccino (capu) lead to defects in polarity establishment of both the anterior/posterior (A/P) and dorsal/ventral (D/V) axes during oogenesis. In the oocytes laid by capu mutant females, determinants that define these axes are either mislocalized or are absent. Several lines of evidence suggest that the regulation of cytoskeleton by the gene product encoded by capu is involved in Drosophila oogenesis.Capu, a member of the formin family of proteins, known to be regulators of actin dynamics, interacts both genetically and physically with chickadee (chic) which encodes the actin binding protein Profilin. I show here that mutations in both capu and chic lead to defects in the endocytic uptake of yolk into developing oocytes. I show that mutations in these loci lead to accumulation of abnormally large yolk granules and that this is a post internalization defect in the oocyte of capu and chic females. I also present evidence which indicates that an interaction with capu is necessary for chic regulation of yolk granule biogenesis.This is the first evidence for a formin subfamily of formin proteins to have a role in endocytosis. While this new function identified for the actin associated proteins Capu and Profilin indicates that regulation of actin cytoskeleton plays a role in endocytosis during oogenesis, the mechanism of this regulation and possible actin independent roles played by Capu and Profilin in this process are yet to be determined.Like capu, mutations in spire (spir) also show defects in A/P and D/V axes during oogenesis. Spir is an actin binding protein and like capu, mutations in spir shows defects in cytoskeletal architecture and suggests that capu and spire alter microtubule distribution in the oocyte during oogenesis.To identify molecular partners of capu and spir and their roles during oogenesis, I performed a genome-wide deficiency screen to identify regions of the genome that interact with these genes. I identified regions in the genome that showed interaction with capu and spir. While I was able to narrow down the region of interaction to a smaller cytological interval, gaps in the deficiency coverage and lack of mutants in those regions prevented me from identifying interacting loci in those regions.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectForminen_US
dc.subjectcappuccinoen_US
dc.subjectspireen_US
dc.subjectchickadeeen_US
dc.subjectendocytosisen_US
dc.subjectyolken_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineMolecular & Cellular Biologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorRamaswami, Manien_US
dc.contributor.chairRamaswami, Manien_US
dc.contributor.committeememberRamaswami, Manien_US
dc.contributor.committeememberBurd, Gailen_US
dc.contributor.committeememberFares, Johnnyen_US
dc.contributor.committeememberMcEvoy, Meganen_US
dc.identifier.proquest1488en_US
dc.identifier.oclc137356276en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.