Filamin is required for ring canal assembly and actin organization during Drosophila oogenesis.
The remodeling of the actin cytoskeleton is essential for cell migration, cell division, and cell morphogenesis. Actin-binding proteins play a pivotal role in reorganizing the actin cytoskeleton in response to signals exchanged between cells. In consequence, actin-binding proteins are increasingly a focus of investigations into effectors of cell signaling and the coordination of cellular behaviors within developmental processes. One of the first actin-binding proteins identified was filamin, or actin-binding protein 280 (ABP280). Filamin is required for cell migration (Cunningham et al. 1992), and mutations in human alpha-filamin (FLN1; Fox et al. 1998) are responsible for impaired migration of cerebral neurons and give rise to periventricular heterotopia, a disorder that leads to epilepsy and vascular disorders, as well as embryonic lethality. We report the identification and characterization of a mutation in Drosophila filamin, the homologue of human alpha-filamin. During oogenesis, filamin is concentrated in the ring canal structures that fortify arrested cleavage furrows and establish cytoplasmic bridges between cells of the germline. The major structural features common to other filamins are conserved in Drosophila filamin. Mutations in Drosophila filamin disrupt actin filament organization and compromise membrane integrity during oocyte development, resulting in female sterility. The genetic and molecular characterization of Drosophila filamin provides the first genetic model system for the analysis of filamin function and regulation during development.
Li
M G
MG
Department of Genetics, Cell and Developmental Biology, University of Minnesota, St. Paul, Minnesota 55108, USA.
Serr
M
M
Edwards
K
K
Ludmann
S
S
Yamamoto
D
D
Tilney
L G
LG
Field
C M
CM
Hays
T S
TS
D000199:Actins / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001692:Biological Transport; D002448:Cell Adhesion; D002462:Cell Membrane / Q000502:physiology; D048429:Cell Size; D003001:Cloning, Molecular; D003285:Contractile Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D004331:Drosophila melanogaster / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D005260:Female; D005298:Fertility; D064448:Filamins; D017344:Genes, Insect / Q000235:genetics / Q000502:physiology; D006801:Humans; D008840:Microfilament Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009866:Oogenesis / Q000502:physiology*; D010053:Ovary / Q000002:abnormalities / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D000199:Actins; D003285:Contractile Proteins; C578663:FLNA protein, human; C578661:FLNC protein, human; D064448:Filamins; D008840:Microfilament Proteins; D010455:Peptides