Title: | The Sub-Chromosomic Macronuclear Pheromone Genes of the Ciliate Euplotes raikovi: Comparative Structural Analysis and Insights into the Mechanism of Expression |
Author(s): | Ricci F; Candelori A; Brandi A; Alimenti C; Luporini P; Vallesi A; |
Address: | "School of Biosciences and Veterinary Medicine, University of Camerino, Camerino (MC), 62032, Italy" |
ISSN/ISBN: | 1550-7408 (Electronic) 1066-5234 (Linking) |
Abstract: | "In Euplotes raikovi, we have determined the full-length sequences of a family of macronuclear genes that are the transcriptionally active versions of codominant alleles inherited at the mating-type (mat) locus of the micronuclear genome, and encode cell type-distinctive signaling pheromones. These genes include a 225-231-bp coding region flanked by a conserved 544-bp 5'-leader region and a more variable 3'-trailer region. Two transcription initiation start sites and two polyadenylation sites associated with nonconventional signals cooperate with a splicing phenomenon of a 326-bp intron residing in the 5'-leader region in the generation of multiple transcripts from the same gene. In two of them, the synthesis of functional products depends on the reassignment to a sense codon, or readthrough of a strictly conserved leaky UAG stop codon. That this reassignment may take place is suggested by the position this codon occupies in the transcripts, close to the transcript extremity and far from the poly(A) tail. In such a case, one product is a 69-amino acid protein in search of function and the second product is a 126-amino acid protein that represents a membrane-bound pheromone isoform candidate to function as a cell type-specific binding site (receptor) of the soluble pheromones" |
Keywords: | "Amino Acid Sequence Euplotes/*genetics *Gene Expression *Genes, Protozoan Pheromones/*genetics Sequence Alignment Ciliate mating types gene structure and expression gene-size DNA molecules pheromone signaling sub-chromosomic genes;" |
Notes: | "MedlineRicci, Francesca Candelori, Annalisa Brandi, Anna Alimenti, Claudio Luporini, Pierangelo Vallesi, Adriana eng Research Support, Non-U.S. Gov't 2018/08/05 J Eukaryot Microbiol. 2019 May; 66(3):376-384. doi: 10.1111/jeu.12677. Epub 2018 Aug 25" |