alexa Biochemical characterization of a membrane androgen receptor in the ovary of the atlantic croaker (Micropogonias undulatus).
Diabetes & Endocrinology

Diabetes & Endocrinology

Journal of Steroids & Hormonal Science

Author(s): Braun AM, Thomas P

Abstract Share this page

Abstract Membrane androgen receptors have been biochemically characterized in only a few vertebrate species to date. Therefore, the purpose of the current study was to comprehensively investigate the binding characteristics of a putative membrane androgen receptor in the ovary of the teleost, Atlantic croaker (Micropogonias undulatus). Specific androgen binding to an ovarian plasma membrane fraction was demonstrated using a radioreceptor assay protocol consisting of a short-term incubation with [(3)H]testosterone (T) and subsequent filtration of bound steroid from free steroid. Saturation and Scatchard analyses of T binding to an ovarian plasma membrane fraction indicated the presence of a single, high-affinity (K(d) = 15.32 +/- 2.68 nM [mean +/- SEM]), low-capacity (B(max) = 2.81 +/- 0.31 pmol/mg protein), androgen-binding site. Specific androgen binding to the receptor was readily displaceable, and the association and dissociation kinetics were rapid (half-time = 3.7 +/- 1.7 and 4.7 +/- 0.2 min, respectively). Competitive binding assays showed that 5alpha-dihydrotestosterone, T, and 11-ketotestosterone had relative binding affinities (RBAs) of 193\%, 100\%, and 13\%, respectively, whereas none of the C(18) or C(21) steroids tested bound with high affinity except for progesterone (RBA = 191\%). This androgen-binding moiety with high affinity for progesterone is unlikely to mediate the physiological actions of progestins in croaker, because it has low binding affinity for fish progestin hormones. Androgen-binding sites were also detected in membrane fractions of the brain, liver, kidney, and drumming muscle, whereas little or no binding was detected in the trunk muscle, heart, gills, or intestine. Receptor levels increased 10-fold during ovarian recrudescence, reaching maximum levels in fully mature ovaries, which suggests a likely physiological role for this receptor during the reproductive cycle of female croaker. It is concluded that the androgen-binding moiety identified in the plasma membrane fraction of Atlantic croaker ovarian tissue fulfils all the criteria for its designation as a steroid receptor. This article was published in Biol Reprod and referenced in Journal of Steroids & Hormonal Science

Relevant Expert PPTs

Relevant Speaker PPTs

  • Yi-Cheng Hu
    Detection of a negative correlation between prescription of Chinese herbal products containing coumestrol, genistein or daidzein and risk of subsequent endometrial cancer among tamoxifentreated female breast cancer survivors in Taiwan between 1998 and 2008: A population-based study
    PPT Version | PDF Version
  • Arvind Goyal
    The effect of pelvic muscle exercises on urinary incontinency and self-esteem of elderly females with stress urinary incontinency, 2013
    PPT Version | PDF Version
  • Randhawa Ramanpreet
    Receiver Operating Characteristic curve analysis of Anthropometric Physiological and Biochemical indices and a comparison between four International definitions JSS, mATP-III, IDF and ATP-III for screening Metabolic Syndrome among Pre- and Postmenopausal Rural females of Amritsar (Punjab)
    PPT Version | PDF Version
  • Asma Javed
    Screening and Management of the female athlete triad
    PPT Version | PDF Version
  • Ashraf El Metwally
    Predictors of pap screening rates among female university students in Maritime Canada
    PPT Version | PDF Version
  • Audrey Steenbeek
    Predictors of pap screening rates among female university students in Maritime Canada
    PPT Version | PDF Version
  • Benicio Gutiérrez-Doña
    Structural equation modeling of male/female handwashing behaviors during the a (H1N1) pandemic influenza in 2009-2010
    PPT Version | PDF Version
  • Amila Orucevic
    Prognostic value of ER, PR, and HER2 breast cancer biomarkers and AJCC’s TNM staging system on overall survival of Caucasian females with breast cancer: An institution’s 10 year experience
    PPT Version | PDF Version
  • Dorcas Ikhuenbor
    Female gender participation in the blood donation process in resource poor settings: Case study of Sokoto in North Western Nigeria
    PPT Version | PDF Version
  • Martha M Sklavos
    Anti-Müllerian hormone deficiency in females with inherited bone marrow failure syndromes
    PDF Version

Recommended Conferences

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords