Impaired microRNA processing causes corpus luteum insufficiency and infertility in mice.

The microRNA (miRNA) processing enzyme Dicer1 is required for zygotic and embryonic development, but the early embryonic lethality of Dicer1 null alleles in mice has limited our ability to address the role of Dicer1 in normal mouse growth and development. To address this question, we used a mouse mutant with a hypomorphic Dicer1 allele (Dicer(d/d)) and found that Dicer1 deficiency resulted in female infertility. This defect in female Dicer(d/d) mice was caused by corpus luteum (CL) insufficiency and resulted, at least in part, from the impaired growth of new capillary vessels in the ovary.