Evidence that sex chromosome genes affect sexual differentiation of female sexual behavior

• Published in: Hormones and behavior 2012-05, Vol.61 (5), p.719-724
• Main Authors: Grgurevic, Neza, Büdefeld, Tomaz, Spanic, Tanja, Tobet, Stuart A., Majdic, Gregor
• Format: Article
• Language: English
• Subjects: Animal reproduction; Animals; Behavioral psychophysiology; Biological and medical sciences; Female; Female sex behavior; Fundamental and applied biological sciences. Psychology; Genes; Hormones and behavior; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Posture - physiology; Progesterone receptor; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Receptors, Progesterone - metabolism; Rodentia - genetics; Rodentia - metabolism; Rodentia - physiology; Rodents; Sex Characteristics; Sex Chromosomes - genetics; Sex Chromosomes - physiology; Sex difference; Sex Differentiation - genetics; Sexual Behavior, Animal - physiology; Steroidogenic factor 1; Steroidogenic Factor 1 - genetics
• ISSN: 0018-506X; 1095-6867
• DOI: 10.1016/j.yhbeh.2012.03.008

Female receptivity including the immobile hormone-dependent lordosis posture is essential for successful reproduction in rodents. It is well documented that lordosis is organized during the perinatal period when the actions of androgens decrease the males' ability to display this behavior in adulthood. Conversely the absence of androgens, and the presence of low levels of prepubertal estrogens, preserve circuitry that regulates this behavior in females. The current study set out to determine whether sex chromosomal genes are involved in the differentiation of this behavior. An agonadal mouse model was used to test this hypothesis. The SF-1 gene (Nr5a1) is required for development of gonads and adrenal glands, and knockout mice are consequently not exposed to endogenous gonadal steroids. Thus contributions of sex chromosome genes can be disassociated from the actions of estrogens. Use of this model reveals a direct genetic contribution from sex chromosomes in the display of lordosis and other female-typical sexual behavior patterns. It is likely that the concentrations of gonadal steroids present during normal male development modify the actions of sex chromosome genes on the potential to display female sexual behavior. ► SF-1 KO mice are born without gonads, male and female mice are thus phenotypically females. ► Female SF-1 KO mice display more robust female sex behavior than SF-1 KO male mice. ► Female SF-1 KO mice have more progesterone receptor immunopositive cells than male SF-1 KO mice. ► Sex chromosome genes contribute to the development of sex difference in female sex behavior.