Conditional kisspeptin neuron-specific <i>Kiss1</i> knockout with newly generated <i>Kiss1</i>-floxed and <i>Kiss1</i>-Cre mice replicates a hypogonadal phenotype of global <i>Kiss1</i> knockout mice
Kana Ikegami, Teppei Goto, Sho Nakamura, Youki Watanabe, Arisa Sugimoto, Sutisa Majarune, Kei Horihata, Mayuko Nagae, Junko Tomikawa, Takuya Imamura, Makoto Sanbo, Masumi Hirabayashi, Naoko Inoue, Kei-ichiro Maeda, Hiroko Tsukamura, Yoshihisa Uenoyama
Abstract
The present study aimed to evaluate whether novel conditional kisspeptin neuron-specific Kiss1 knockout (KO) mice utilizing the Cre-loxP system could recapitulate the infertility of global Kiss1 KO models, thereby providing further evidence for the fundamental role of hypothalamic kisspeptin neurons in regulating mammalian reproduction. We generated Kiss1-floxed mice and hypothalamic kisspeptin neuron-specific Cre-expressing transgenic mice and then crossed these two lines. The conditional Kiss1 KO mice showed pubertal failure along with a suppression of gonadotropin secretion and ovarian atrophy. These results indicate that newly-created hypothalamic Kiss1 KO mice obtained by the Cre-loxP system recapitulated the infertility of global Kiss1 KO models, suggesting that hypothalamic kisspeptin, but not peripheral kisspeptin, is critical for reproduction. Importantly, these Kiss1-floxed mice are now available and will be a valuable tool for detailed analyses of roles of each population of kisspeptin neurons in the brain and peripheral kisspeptin-producing cells by the spatiotemporal-specific manipulation of Cre expression.