Drosophila processing bodies in oogenesis

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2008.07.033 Byline: Ming-Der Lin (a), Xinfu Jiao (b), Dominic Grima (c), Sarah F. Newbury (c), Megerditch Kiledjian (b), Tze-Bin Chou (a) Keywords: Processing bodies; Drosophila decapping protein 1; Drosophila decapping protein 2; Pacman; Me31B; Oogenesis Abstract: Processing bodies (P-bodies) have emerged as important subcellular structures that are involved in mRNA metabolism. To date, a detailed description of P-bodies in Drosophila oogenesis is lacking. To this end, we first demonstrate that Drosophila decapping protein 2 (dDcp2) contains intrinsic decapping activity and its enzymatic activity was not detectably enhanced by Drosophila decapping protein 1 (dDcp1). dDcp1-containing bodies in the nurse cell cytoplasm can associate with the 5' to 3' exoribonuclease, Pacman in addition to dDcp2 and Me31B. The size and number of dDcp1 bodies are dynamic and dramatically increased in dDcp2 and pacman mutant backgrounds supporting the conclusion that dDcp1 bodies in nurse cell cytoplasm are Drosophila P-bodies. In stage 2-6 oocytes, dDcp1 bodies appear to be distinct from previously characterized P-bodies since they are insensitive to cycloheximide and RNase A treatments. Curiously, dDcp2 and Pacman do not colocalize with dDcp1 at the posterior end of the oocyte in stage 9-10 oocytes. This suggests that dDcp1 bodies are in a developmentally distinct state separate from the 5' end mRNA degradation enzymes at later stages in the oocyte. Interestingly, re-formation of maternally expressed dDcp1 with dDcp2 and Pacman was observed in early embryogenesis. With respect to developmental switching, the maternal dDcp1 is proposed to serve as a marker for the re-formation of P-bodies in early embryos. This also suggests that a regulated conversion occurs between maternal RNA granules and P-bodies from oogenesis to embryogenesis. Author Affiliation: (a) Institute of Molecular and Cellular Biology, College of Life Science, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (b) Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ 08854-8082, USA (c) Brighton and Sussex Medical School, University of Sussex, Falmer, Brighton, BN1 9QG, UK Article History: Received 27 February 2008; Revised 14 July 2008; Accepted 15 July 2008