Phylogenetic comparison of oskar mRNA localization signals.
As a way to spatially control the expression of genes within cells, RNA localization is being recognized as an important process by which proteins are restricted to specific subcellular domains, which occurs in more diverse types of tissue than previously considered. Although many localized RNAs have been identified, information on cis-acting elements of localization is still limited. As transcripts of oskar (osk) are known to localize to the posterior pole of oocytes, we computationally analyzed a conserved sequence among eight Drosophila species and tested its role as a localization element. Dimerization of osk mRNA did not occur when the motif was deleted, but this did not affect assembly of osk mRNA-containing ribonucleoprotein (RNP) complexes. Without the motif, however, large RNP complex particles accumulated in nurse cells, and only a small fraction of these RNP complexes was transported into oocytes and properly localized to the posterior pole. Therefore, this motif may be required for the early transport of osk mRNA into oocytes. Also, as dimerization of osk mRNA does not seem to be a prerequisite for the assembly of RNP complexes, a dimerization-independent mechanism may also serve to localize osk mRNA to the posterior pole.
Department of Molecular Biology, College of Life Sciences, Sejong University, 98 Kunja-Dong, Kwangjin-ku, Seoul, South Korea.
Jihyun
J
Kim
Department of Molecular Biology, College of Life Sciences, Sejong University, 98 Kunja-Dong, Kwangjin-ku, Seoul, South Korea.
Jiyeon
J
Lee
Department of Molecular Biology, College of Life Sciences, Sejong University, 98 Kunja-Dong, Kwangjin-ku, Seoul, South Korea.
Sujung
S
Lee
Department of Molecular Biology, College of Life Sciences, Sejong University, 98 Kunja-Dong, Kwangjin-ku, Seoul, South Korea.
Borim
B
Lee
Department of Molecular Biology, College of Life Sciences, Sejong University, 98 Kunja-Dong, Kwangjin-ku, Seoul, South Korea. Electronic address: jsha@sejong.ac.kr.
Jeongsil
J
Kim-Ha
D020413:3' Untranslated Regions; D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D017124:Conserved Sequence; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism; D005260:Female; D017344:Genes, Insect; D008969:Molecular Sequence Data; D009865:Oocytes / Q000378:metabolism; D010802:Phylogeny; D034443:RNA Transport; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics; D013045:Species Specificity
D020413:3' Untranslated Regions; D029721:Drosophila Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C091675:osk protein, Drosophila
Drosophila; Localization element; Oogenesis; Phylogeny; RNA transport; oskar