title: RNA immunoprecipitation identifies novel targets of DAZL in human foetal ovary.
abstract: Can novel meiotic RNA targets of DAZL (deleted in azoospermia-like) be identified in the human foetal ovary?
  
  
  
  SYCP1 (synaptonemal complex protein-1), TEX11 (testis expressed 11) and SMC1B (structural maintenance of chromosomes 1B) are novel DAZL targets in the human foetal ovary, thus DAZL may have previously unrecognised roles in the translational regulation of RNAs involved in chromosome cohesion and DNA recombination in the oocyte from the time of initiation of meiosis.
  
  
  
  The phenotype of Dazl deficiency in mouse is infertility in both sexes and DAZL has also been linked to infertility in humans. Few studies have explored targets of this RNA-binding protein. The majority of these investigations have been carried out in mouse, and have focussed on the male thus the basis for its central function in regulating female fertility is largely unknown.
  
  
  
  We carried out RNA sequencing after immunoprecipitation of endogenous DAZL from human foetal ovarian tissue (17 weeks of gestation, obtained after elective termination of pregnancy) to identify novel DAZL targets involved in meiosis (n = 3 biological replicates).
  
  
  
  Using quantitative RT-PCR, we examined the expression of selected RNAs identified by our immunoprecipitation across gestation, and visualised the expression of potential target SMC1B in relation to DAZL, with a combination of in situ hybridisation and immunohistochemistry. 3' untranslated region (3'UTR)-luciferase reporter assays and polysome profile analysis were used to investigate the regulation of three RNA targets by DAZL, representing key functionalities: SYCP1, TEX11 and SMC1B.
  
  
  
  We identified 764 potential RNA targets of DAZL in the human foetal ovary (false discovery rate 0.05 and log-fold change ≥ 2), with functions in synaptonemal complex formation (SYCP1, SYCP3), cohesin formation (SMC1B, RAD21), spindle assembly checkpoint (MAD2L1, TRIP13) and recombination and DNA repair (HORMAD1, TRIP13, TEX11, RAD18, RAD51). We demonstrated that the translation of novel targets SYCP1 (P = 0.004), TEX11 (P = 0.004) and SMC1B (P = 0.002) is stimulated by the presence of DAZL but not by a mutant DAZL with impaired RNA-binding activity.
  
  
  
  The raw data are available at GEO using the study ID: GSE81524.
  
  
  
  This analysis is based on identification of DAZL targets at the time when meiosis starts in the ovary: it may have other targets at other stages of oocyte development, and in the testis. Representative targets were validated, but detailed analysis was not performed on the majority of putative targets.
  
  
  
  These data indicate roles for DAZL in the regulation of several key functions in human oocytes. Through the translational regulation of novel RNA targets SMC1B and TEX11, DAZL may have a key role in regulating chromosome cohesion and DNA recombination; two processes fundamental in determining oocyte quality and whose establishment in foetal life may support lifelong fertility.
  
  
  
  This study was supported by the UK Medical Research Council (grant no G1100357 to R.A.A. and an intramural MRC programme grant to I.R.A.). The authors declare no competing interests.
authors.affiliation: MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK.
authors.forename: Roseanne
authors.initials: R
authors.lastname: Rosario
authors.affiliation: MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK.
authors.forename: Richard W P
authors.initials: RW
authors.lastname: Smith
authors.affiliation: MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, Edinburgh EH4 2XU, UK.
authors.forename: Ian R
authors.initials: IR
authors.lastname: Adams
authors.affiliation: MRC Centre for Reproductive Health, Queens Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Anderson
mesh_terms: D000029:Abortion, Legal; D000818:Animals; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics* / Q000378:metabolism; D002875:Chromosomes / Q000737:chemistry / Q000378:metabolism; D004268:DNA-Binding Proteins; D005260:Female; D005298:Fertility / Q000235:genetics*; D005333:Fetus / Q000166:cytology / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D005865:Gestational Age; D057809:HEK293 Cells; D006801:Humans; D008540:Meiosis; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D009865:Oocytes / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D010053:Ovary / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D011247:Pregnancy; D011485:Protein Binding; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D011995:Recombination, Genetic; D015398:Signal Transduction
chemical_list: D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; C101358:DAZL protein, human; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C000611898:SMC1B protein, human; C489753:SYCP1 protein, human; C000598435:TEX11 protein, human
keywords: DAZL; RNA targets; female fertility; meiosis