['To demonstrate interregulation between FOXL2 and antimüllerian hormone (AMH) in ovarian folliculogenesis.', 'Cell culture and animal study.', 'University research laboratory.', 'Five-week-old B6C3F1 mice.', 'Molecular analysis and in\xa0vivo mouse experiment were performed to demonstrate that AMH is a target gene of FOXL2 in the ovary.', 'To determine whether FOXL2 transactivates AMH, luciferase reporter assay, electrophoretic mobility shift assay, and chromatin immuniprecipitation were conducted. Using an in\xa0vivo nucleic acid delivery system, the expression of AMH and/or FOXL2 was modulated in the mouse, and the ovaries were histologically analyzed.', 'AMH is an endogenous target gene of FOXL2. In contrast, mutated FOXL2s found in premature ovarian failure patients were defective in their ability to activate AMH transcription in human granulosa cells. In\xa0vivo mouse gene delivery experiments revealed that Amh-knockdown accelerated follicle growth; however, the acceleration was prevented by ectopic expression of FOXL2.'] Does positive cross talk between FOXL2 and antimüllerian hormone regulate ovarian reserve?