TY - JOUR
T1 - Bicaudal-C associates with a Trailer Hitch/Me31B complex and is required for efficient Gurken secretion
AU - Kugler, Jan-Michael
AU - Chicoine, Jarred
AU - Lasko, Paul
PY - 2009/4/1
Y1 - 2009/4/1
N2 - Bicaudal-C (Bic-C) is a multiple KH-domain RNA-binding protein required for Drosophila oogenesis and, maternally, for embryonic patterning. In early oogenesis, Bic-C negatively regulates target mRNAs, including Bic-C, by recruiting the CCR4 deadenylase through a direct association with its NOT3 subunit. Here, we identify a novel function for Bic-C in secretion of the TGF-alpha homolog Gurken (Grk). In Bic-C mutant egg chambers, Grk is sequestered within actin-coated structures during mid-oogenesis. As a consequence, Egfr signalling is not efficiently activated in the dorsal-anterior follicle cells. This phenotype is strikingly similar to that of trailer hitch (tral) mutants. Consistent with the idea that Bic-C and Tral act together in Grk secretion, Bic-C co-localizes with Tral within cytoplasmic granules, and can be co-purified with multiple protein components of a Tral mRNP complex. Taken together, our results implicate translational regulation by Bic-C and Tral in the secretory pathway.
AB - Bicaudal-C (Bic-C) is a multiple KH-domain RNA-binding protein required for Drosophila oogenesis and, maternally, for embryonic patterning. In early oogenesis, Bic-C negatively regulates target mRNAs, including Bic-C, by recruiting the CCR4 deadenylase through a direct association with its NOT3 subunit. Here, we identify a novel function for Bic-C in secretion of the TGF-alpha homolog Gurken (Grk). In Bic-C mutant egg chambers, Grk is sequestered within actin-coated structures during mid-oogenesis. As a consequence, Egfr signalling is not efficiently activated in the dorsal-anterior follicle cells. This phenotype is strikingly similar to that of trailer hitch (tral) mutants. Consistent with the idea that Bic-C and Tral act together in Grk secretion, Bic-C co-localizes with Tral within cytoplasmic granules, and can be co-purified with multiple protein components of a Tral mRNP complex. Taken together, our results implicate translational regulation by Bic-C and Tral in the secretory pathway.
KW - Animals
KW - DEAD-box RNA Helicases
KW - Drosophila
KW - Drosophila Proteins
KW - Embryo, Nonmammalian
KW - Mutation
KW - Oogenesis
KW - RNA-Binding Proteins
KW - Ribonucleoproteins
KW - Transforming Growth Factor alpha
U2 - 10.1016/j.ydbio.2009.01.024
DO - 10.1016/j.ydbio.2009.01.024
M3 - Journal article
C2 - 19389362
SN - 0012-1606
VL - 328
SP - 160
EP - 172
JO - Developmental Biology
JF - Developmental Biology
IS - 1
ER -