title: Novel genes and hormonal regulation for gonadal development during embryogenesis in chickens.
abstract: Asymmetrical gonadal morphogenesis is well known in female chickens in contrast to males where both gonads develop symmetrically. However, only a few genes have been reported to determine differential morphology between female and male gonads in chicken and their mechanisms of action are unclear. Therefore, we focused on three genes (TOM1L1, TTR, and ZEB1) that are related to cellular proliferation and embryonic development based on previous study indicating up- or down-regulated transcripts in the asymmetric female gonads between embryonic day 6 (E6) and E9 by microarray analyses. To define the validity of the gene expression pattern discovered, q-PCR and in situ hybridization analyses were performed. In the left female gonad between E6 and E9 the expression of TOM1L1, TTR and ZEB1 increased at E9. On the other hand, TOM1L1 and TTR increased significantly in both male gonads between E6 and E9. In addition, recombinant FSH and LH stimulated proliferation of gonadal cells and influenced expression of selected genes in chickens. This suggests that hormonal regulation is involved in growth and development in the embryonic gonad of chickens. Collectively, the results show differential gene expression between the left and right gonads in chicken embryos and that of is regulated by gonadotropin. These results provide novel insights into candidate genes regulating gonad development and differentiation.
authors.affiliation: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea.
authors.forename: Whasun
authors.initials: W
authors.lastname: Lim
authors.affiliation: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea. Electronic address: ghsong@korea.ac.kr.
authors.forename: Gwonhwa
authors.initials: G
authors.lastname: Song
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000235:genetics / Q000378:metabolism; D002642:Chick Embryo; D002645:Chickens / Q000235:genetics*; D047108:Embryonic Development / Q000235:genetics*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006066:Gonads / Q000196:embryology* / Q000378:metabolism*; D006728:Hormones / Q000378:metabolism*; D006801:Humans; D017403:In Situ Hybridization; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D010053:Ovary / Q000378:metabolism; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D013737:Testis / Q000378:metabolism; D013997:Time Factors
chemical_list: D030161:Avian Proteins; D006728:Hormones; D012333:RNA, Messenger; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone
keywords: Asymmetric development; Chicken; Embryo; Gonad; Reproductive hormones