| Title: | Functional chimeric genes in ciliates: An instructive case from Euplotes raikovi |
| Author(s): | Ricci F; Luporini P; Alimenti C; Vallesi A; |
| Address: | "Laboratory of Eukaryotic Microbiology and Animal Biology, School of Biosciences and Veterinary Medicine, University of Camerino, Camerino 62032, Italy. Laboratory of Eukaryotic Microbiology and Animal Biology, School of Biosciences and Veterinary Medicine, University of Camerino, Camerino 62032, Italy. Electronic address: adriana.vallesi@unicam.it" |
| DOI: | 10.1016/j.gene.2020.145186 |
| ISSN/ISBN: | 1879-0038 (Electronic) 0378-1119 (Linking) |
| Abstract: | "In ciliates, with every sexual event the transcriptionally active genes of the sub-chromosomic somatic genome that resides in the cell macronucleus are lost. They are de novo assembled starting from 'Macronuclear Destined Sequences' that arise from the fragmentation of transcriptionally silent DNA sequences of the germline chromosomic genome enclosed in the cell micronucleus. The RNA-mediated epigenetic mechanism that drives the assembly of these sequences is subject to errors which result in the formation of chimeric genes. Studying a gene family that in Euplotes raikovi controls the synthesis of protein signal pheromones responsible for a self/not-self recognition mechanism, we identified the chimeric structure of an 851-bp macronuclear gene previously known to specify soluble and membrane-bound pheromone molecules through an intron-splicing mechanism. This chimeric gene, designated mac-er-1*, conserved the native pheromone-gene structure throughout its coding and 3' regions. Instead, its 5' region is completely unrelated to the pheromone gene structure at the level of a 360-bp sequence, which derives from the assembly with a MDS destined to compound a 2417-bp gene encoding a 696-amino acid protein with unknown function. This mac-er-1* gene characterization provides further evidence that ciliates rely on functional chimeric genes that originate in non-programmed phenomena of somatic MDS recombination to increase the species genetic variability independently of gene reshuffling phenomena of the germline genome" |
| Keywords: | Amino Acid Sequence/genetics Base Sequence/genetics Chimera/*genetics Ciliophora/genetics DNA/genetics Euplotes/*genetics Gene Rearrangement/genetics Introns/genetics Pheromones/*genetics RNA/genetics RNA Splicing/genetics Chimeric genes Euplotes macronuc; |
| Notes: | "MedlineRicci, Francesca Luporini, Pierangelo Alimenti, Claudio Vallesi, Adriana eng Netherlands 2020/10/01 Gene. 2021 Jan 30; 767:145186. doi: 10.1016/j.gene.2020.145186. Epub 2020 Sep 28" |
