Asterless is a centriolar protein required for centrosome function and embryo development in Drosophila.
BACKGROUND
Centrosomes, the major organizers of the microtubule network in most animal cells, are composed of centrioles embedded in a web of pericentriolar material (PCM). Recruitment and stabilization of PCM on the centrosome is a centriole-dependent function. Compared to the considerable number of PCM proteins known, the molecular characterization of centrioles is still very limited. Only a few centriolar proteins have been identified so far in Drosophila, most related to centriole duplication.


RESULTS
We have cloned asterless (asl) and found that it encodes a 120 kD highly coiled-coil protein that is a constitutive pancentriolar and basal body component. Loss of asl function impedes the stabilization/maintenance of PCM at the centrosome. In embryos deficient for Asl, development is arrested right after fertilization. Asl shares significant homology with Cep 152, a protein described as a component of the human centrosome for which no functional data is yet available.


CONCLUSIONS
The cloning of asl offers new insight into the molecular composition of Drosophila centrioles and a possible model for the role of its human homolog. In addition, the phenotype of asl-deficient flies reveals that a functional centrosome is required for Drosophila embryo development.
Varmark
Hanne
H
Cell Biology and Biophysics Programme, European Molecular Biology Laboratory, Meyerhofstrasse, D-69117 Heidelberg, Germany.
Llamazares
Salud
S
Rebollo
Elena
E
Lange
Bodo
B
Reina
Jose
J
Schwarz
Heinz
H
Gonzalez
Cayetano
C
D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D002502:Centrioles / Q000502:physiology*; D018385:Centrosome / Q000502:physiology*; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics / Q000502:physiology*; D047108:Embryonic Development / Q000235:genetics / Q000502:physiology; D005260:Female; D017344:Genes, Insect; D006801:Humans; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid
D017931:DNA Primers; D029721:Drosophila Proteins