title: High contaminant loads in Lake Apopka's riparian wetland disrupt gene networks involved in reproduction and immune function in largemouth bass.
abstract: Lake Apopka (FL, USA) has elevated levels of some organochlorine pesticides in its sediments and a portion of its watershed has been designated a US Environmental Protection Agency Superfund site. This study assessed reproductive endpoints in Florida largemouth bass (LMB) (Micropterus salmoides floridanus) after placement into experimental ponds adjacent to Lake Apopka. LMB collected from a clean reference site (DeLeon Springs) were stocked at two periods of time into ponds constructed in former farm fields on the north shore of the lake. LMB were stocked during early and late oogenesis to determine if there were different effects of contamination on LMB that may be attributed to their reproductive stage. LMB inhabiting the ponds for ~4months had anywhere from 2 to 800 times higher contaminant load for a number of organochlorine pesticides (e.g. p, p'-DDE, methoxychlor) compared to control animals. Gonadosomatic index and plasma vitellogenin were not different between reproductively-stage matched LMB collected at reference sites compared to those inhabiting the ponds. However, plasma 17β-estradiol was lower in LMB inhabiting the Apopka ponds compared to ovary stage-matched LMB from the St. Johns River, a site used as a reference site. Sub-network enrichment analysis revealed that genes related to reproduction (granulosa function, oocyte development), endocrine function (steroid metabolism, hormone biosynthesis), and immune function (T cell suppression, leukocyte accumulation) were differentially expressed in the ovaries of LMB placed into the ponds. These data suggest that (1) LMB inhabiting the Apopka ponds showed disrupted reproduction and immune responses and that (2) gene expression profiles provided site-specific information by discriminating LMB from different macro-habitats.
authors.affiliation: Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA. Electronic address: cmartyn@ufl.edu.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Martyniuk
authors.affiliation: Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Doperalski
authors.affiliation: Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Melinda S
authors.initials: MS
authors.lastname: Prucha
authors.affiliation: Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Ji-Liang
authors.initials: JL
authors.lastname: Zhang
authors.affiliation: Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Kroll
authors.affiliation: St. Johns River Water Management District, Palatka, FL 32177, USA.
authors.forename: Roxanne
authors.initials: R
authors.lastname: Conrow
authors.affiliation: Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: David S
authors.initials: DS
authors.lastname: Barber
authors.affiliation: Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA. Electronic address: ndenslow@ufl.edu.
authors.forename: Nancy D
authors.initials: ND
authors.lastname: Denslow
mesh_terms: D000818:Animals; D001492:Bass / Q000235:genetics* / Q000254:growth & development; D019295:Computational Biology; D053263:Gene Regulatory Networks / Q000187:drug effects*; D007111:Immunity, Cellular / Q000187:drug effects / Q000235:genetics*; D060106:Lakes; D046228:Microarray Analysis; D012098:Reproduction / Q000187:drug effects / Q000235:genetics*; D059467:Transcriptome / Q000187:drug effects*; D014819:Vitellogenins / Q000097:blood; D014874:Water Pollutants, Chemical / Q000494:pharmacology*; D053833:Wetlands
chemical_list: D014819:Vitellogenins; D014874:Water Pollutants, Chemical
keywords: Environmental genomics; Environmental monitoring; Field study; Organochlorine pesticides; Sub-network enrichment analysis