title: GPCRs Direct Germline Development and Somatic Gonad Function in Planarians.
abstract: Planarians display remarkable plasticity in maintenance of their germline, with the ability to develop or dismantle reproductive tissues in response to systemic and environmental cues. Here, we investigated the role of G protein-coupled receptors (GPCRs) in this dynamic germline regulation. By genome-enabled receptor mining, we identified 566 putative planarian GPCRs and classified them into conserved and phylum-specific subfamilies. We performed a functional screen to identify NPYR-1 as the cognate receptor for NPY-8, a neuropeptide required for sexual maturation and germ cell differentiation. Similar to NPY-8, knockdown of this receptor results in loss of differentiated germ cells and sexual maturity. NPYR-1 is expressed in neuroendocrine cells of the central nervous system and can be activated specifically by NPY-8 in cell-based assays. Additionally, we screened the complement of GPCRs with expression enriched in sexually reproducing planarians, and identified an orphan chemoreceptor family member, ophis, that controls differentiation of germline stem cells (GSCs). ophis is expressed in somatic cells of male and female gonads, as well as in accessory reproductive tissues. We have previously shown that somatic gonadal cells are required for male GSC specification and maintenance in planarians. However, ophis is not essential for GSC specification or maintenance and, therefore, defines a secondary role for planarian gonadal niche cells in promoting GSC differentiation. Our studies uncover the complement of planarian GPCRs and reveal previously unappreciated roles for these receptors in systemic and local (i.e., niche) regulation of germ cell development.
authors.affiliation: Howard Hughes Medical Institute and Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America.
authors.forename: Amir
authors.initials: A
authors.lastname: Saberi
authors.affiliation: Howard Hughes Medical Institute and Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America.
authors.forename: Ayana
authors.identifier: 0000-0002-3380-2005
authors.initials: A
authors.lastname: Jamal
authors.affiliation: Department of Biology, Functional Genomics and Proteomics Unit, KU Leuven, Leuven, Belgium.
authors.forename: Isabel
authors.initials: I
authors.lastname: Beets
authors.affiliation: Department of Biology, Functional Genomics and Proteomics Unit, KU Leuven, Leuven, Belgium.
authors.forename: Liliane
authors.initials: L
authors.lastname: Schoofs
authors.affiliation: Howard Hughes Medical Institute and Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America.
authors.forename: Phillip A
authors.initials: PA
authors.lastname: Newmark
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D005260:Female; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D055106:Genome-Wide Association Study; D015801:Helminth Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D055099:Neuroendocrine Cells / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism; D010063:Ovum / Q000254:growth & development* / Q000378:metabolism; D010932:Planarians / Q000235:genetics / Q000254:growth & development*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics* / Q000378:metabolism; D017476:Receptors, Neuropeptide Y / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013094:Spermatozoa / Q000254:growth & development* / Q000378:metabolism; D013737:Testis / Q000254:growth & development
chemical_list: D015801:Helminth Proteins; D009478:Neuropeptide Y; D043562:Receptors, G-Protein-Coupled; D017476:Receptors, Neuropeptide Y