Drosophila Dynein light chain (DDLC1) binds to gurken mRNA and is required for its localization.
During oogenesis in Drosophila, mRNAs encoding determinants required for the polarization of egg and embryo become localized in the oocyte in a spatially restricted manner. The TGF-alpha like signaling molecule Gurken has a central role in the polarization of both body axes and the corresponding mRNA displays a unique localization pattern, accumulating initially at the posterior and later at the anterior-dorsal of the oocyte. Correct localization of gurken RNA requires a number of cis-acting sequence elements, a complex of trans-acting proteins, of which only several have been identified, and the motor proteins Dynein and Kinesin, traveling along polarized microtubules. Here we report that the cytoplasmic Dynein-light-chain (DDLC1) which is the cargo-binding subunit of the Dynein motor protein, directly bound with high specificity and affinity to a 230-nucleotide region within the 3'UTR of gurken, making it the first Drosophila mRNA-cargo to directly bind to the DLC. Although DDLC1 lacks known RNA-binding motifs, comparison to double-stranded RNA-binding proteins suggested structural resemblance. Phenotypic analysis of ddlc1 mutants supports a role for DDLC1 in gurken RNA localization and anchoring as well as in correct positioning of the oocyte nucleus.
Rom
Inna
I
Department of Virology and Developmental Genetics, Ben-Gurion University of the Negev Beer-Sheva 84105, Israel.
Faicevici
Alice
A
Almog
Orna
O
Neuman-Silberberg
F Shira
FS
D020413:3' Untranslated Regions; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D004330:Drosophila / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004398:Dyneins; D005260:Female; D005982:Glutathione Transferase / Q000235:genetics; D016547:Kinesins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D009865:Oocytes / Q000378:metabolism; D011485:Protein Binding; D012330:RNA, Double-Stranded / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016211:Transforming Growth Factor alpha / Q000378:metabolism*
D020413:3' Untranslated Regions; D002352:Carrier Proteins; D029721:Drosophila Proteins; D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D016211:Transforming Growth Factor alpha; C542608:ctp protein, Drosophila; C083730:grk protein, Drosophila; D005982:Glutathione Transferase; D004398:Dyneins; D016547:Kinesins