title: Differential gene expression of IGF-I, IGF-II, and toll-like receptors 3 and 5 during embryogenesis in hybrid (channel x blue) and channel catfish.
abstract: Insulin-like growth factors-I and-II (IGF-I and IGF-II) play important roles in growth and development of mammals. Toll-like receptors (TLRs) are pattern recognition molecules that orchestrate the induction of early innate immune response by recognition of specific sequences. Evidence is growing that suggests a relationship between growth and immune function. The objective of the study was to examine changes in gene expression of IGF-I, IGF-II, TLR3, and TLR5 during embryogenesis and early larval development in hybrid (channel catfishxblue catfish) and channel catfish. Egg samples were taken pre- and post-fertilization; embryos were collected at two stages of embryogenesis, at hatch, and at swim-up. All genes were detected in unfertilized catfish eggs. Expression levels of TLR5 and IGF-I mRNA in channel catfish and expression levels of TLR3, IGF-I, and IGF-II mRNA in hybrids increased over time (P<0.01). Effect of time was not significant for expression of IGF-II or TLR3 mRNA in channel catfish and for TLR5 mRNA in hybrid catfish. Results of this study suggest growth (IGF-I and IGF-II) and immune (TLR3 and TLR5) associated genes could be functional and play important roles during embryogenesis and early development of hybrid and channel catfish.
authors.affiliation: USDA/ARS Catfish Genetics Research Unit, Thad Cochran National Warmwater Aquaculture Center, P.O. Box 38, Stoneville, MS 38776, USA. bpeterson@ars.usda.gov
authors.forename: Brian C
authors.initials: BC
authors.lastname: Peterson
authors.forename: Brian G
authors.initials: BG
authors.lastname: Bosworth
authors.forename: A Lelania
authors.initials: AL
authors.lastname: Bilodeau
mesh_terms: D000818:Animals; D047108:Embryonic Development / Q000235:genetics; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D006824:Hybridization, Genetic / Q000235:genetics*; D007059:Ictaluridae / Q000196:embryology* / Q000235:genetics* / Q000254:growth & development; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D007814:Larva / Q000235:genetics / Q000254:growth & development; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics*; D051196:Toll-Like Receptor 3; D051198:Toll-Like Receptor 5; D051193:Toll-Like Receptors
chemical_list: D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D051196:Toll-Like Receptor 3; D051198:Toll-Like Receptor 5; D051193:Toll-Like Receptors; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II