Pdsg1 and Pdsg2, novel proteins involved in developmental genome remodelling in Paramecium.
The epigenetic influence of maternal cells on the development of their progeny has long been studied in various eukaryotes. Multicellular organisms usually provide their zygotes not only with nutrients but also with functional elements required for proper development, such as coding and non-coding RNAs. These maternally deposited RNAs exhibit a variety of functions, from regulating gene expression to assuring genome integrity. In ciliates, such as Paramecium these RNAs participate in the programming of large-scale genome reorganization during development, distinguishing germline-limited DNA, which is excised, from somatic-destined DNA. Only a handful of proteins playing roles in this process have been identified so far, including typical RNAi-derived factors such as Dicer-like and Piwi proteins. Here we report and characterize two novel proteins, Pdsg1 and Pdsg2 (Paramecium protein involved in Development of the Somatic Genome 1 and 2), involved in Paramecium genome reorganization. We show that these proteins are necessary for the excision of germline-limited DNA during development and the survival of sexual progeny. Knockdown of PDSG1 and PDSG2 genes affects the populations of small RNAs known to be involved in the programming of DNA elimination (scanRNAs and iesRNAs) and chromatin modification patterns during development. Our results suggest an association between RNA-mediated trans-generational epigenetic signal and chromatin modifications in the process of Paramecium genome reorganization.
Institute of Cell Biology, University of Bern, Bern, Switzerland.
Miroslav
M
Arambasic
Institute of Cell Biology, University of Bern, Bern, Switzerland.
Pamela Y
PY
Sandoval
Institute of Cell Biology, University of Bern, Bern, Switzerland.
Cristina
C
Hoehener
Institute of Cell Biology, University of Bern, Bern, Switzerland.
Aditi
A
Singh
Institute of Cell Biology, University of Bern, Bern, Switzerland.
Estienne C
EC
Swart
Institute of Cell Biology, University of Bern, Bern, Switzerland.
Mariusz
M
Nowacki
D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D016054:DNA, Protozoan / Q000235:genetics / Q000378:metabolism; D044127:Epigenesis, Genetic; D018503:Genome, Protozoan; D006657:Histones / Q000378:metabolism; D008745:Methylation; D018613:Microscopy, Confocal; D010247:Paramecium / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D015800:Protozoan Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
D002843:Chromatin; D016054:DNA, Protozoan; D006657:Histones; D015800:Protozoan Proteins; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins