An Essential Cytoplasmic Function for the Nuclear Poly(A) Binding Protein, PABP2, in Poly(A) Tail Length Control and Early Development in Drosophila

• Published in: Developmental cell 2005-10, Vol.9 (4), p.511-522
• Main Authors: Benoit, Béatrice, Mitou, Géraldine, Chartier, Aymeric, Temme, Claudia, Zaessinger, Sophie, Wahle, Elmar, Busseau, Isabelle, Simonelig, Martine
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Biochemistry; Biochemistry, Molecular Biology; Biological and medical sciences; Body Patterning; Cell Cycle - physiology; Cell differentiation, maturation, development, hematopoiesis; Cell physiology; Cyclin B - genetics; Cyclin B - metabolism; Drosophila melanogaster - embryology; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Embryo, Nonmammalian - anatomy & histology; Embryo, Nonmammalian - physiology; Female; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Developmental; Life Sciences; Male; Molecular and cellular biology; Molecular Sequence Data; Oocytes - physiology; Other; Poly(A)-Binding Protein II - genetics; Poly(A)-Binding Protein II - metabolism; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Ribonucleases - genetics; Ribonucleases - metabolism; RNA, Messenger - metabolism
• ISSN: 1534-5807; 1878-1551
• DOI: 10.1016/j.devcel.2005.09.002

Translational control of maternal mRNA through regulation of poly(A) tail length is crucial during early development. The nuclear poly(A) binding protein, PABP2, was identified biochemically from its role in nuclear polyadenylation. Here, we analyze the in vivo function of PABP2 in Drosophila. PABP2 is required in vivo for polyadenylation, and Pabp2 function, including poly(A) polymerase stimulation, is essential for viability. We also demonstrate an unanticipated cytoplasmic function for PABP2 during early development. In contrast to its role in nuclear polyadenylation, cytoplasmic PABP2 acts to shorten the poly(A) tails of specific mRNAs. PABP2, together with the deadenylase CCR4, regulates the poly(A) tails of oskar and cyclin B mRNAs, both of which are also controlled by cytoplasmic polyadenylation. Both Cyclin B protein levels and embryonic development depend upon this regulation. These results identify a regulator of maternal mRNA poly(A) tail length and highlight the importance of this mode of translational control.