Proper development and function of the female reproductive tract are essential for successful reproduction. Regulation of the differentiated functions of the organs that make up the female reproductive tract is well established to occur at multiple levels including transcription, translation, and posttranslational modifications. Micro-RNA (miRNA)-mediated posttranscriptional gene regulation has emerged as a fundamental mechanism controlling normal tissue development and function. Emerging evidence indicates that miRNAs are expressed within the organs of the female reproductive tract where they function to regulate cellular pathways necessary for proper function of these organs. In this review, the functional significance of miRNAs in the development and function of the organs of the female reproductive tract is discussed. Initial discussion focuses on the role of miRNAs in the development of the organs of the female reproductive tract highlighting recent studies that clearly demonstrate that mice with disrupted Dicer1 expression are sterile, fail to develop uterine glands, and have muted estrogen responsiveness. Next, emphasis moves to discussion on our current knowledge on the characterization of miRNA expression in each of the organs of the female reproductive tract. When possible, information is presented and discussed with respect to regulation, function, and/or functional targets of these miRNA within each specific organ of the female reproductive tract.

Endometriosis is a disease common in women of reproductive age, characterized by pelvic pain and infertility. Despite its prevalence, the factors and mechanisms which contribute to the development and survival of ectopic lesions remain uncertain. MicroRNAs (miRNAs) are small RNA molecules that regulate posttranscriptional gene regulation which have been proposed to contribute to the pathogenesis of many diseases including that of endometriosis. This review summarizes the results of initial studies describing differentially expressed miRNAs between endometriotic lesion tissue and eutopic endometrium. Focus then moves toward discussion of studies on examining function of differentially expressed miRNAs to determine if they play a permissive role (driver of the disease) in events conducive to endometriosis progression/survival. Included in this discussion are the potential targets of these miRNAs and how their mis-expression may contribute to the disease. Limitations and challenges faced in studying miRNAs and endometriosis pathogenesis and recommendations to overcome these hurdles are presented at the end.

Tissue inhibitor of metalloproteinase-1 (TIMP-1) is a multifunctional protein expressed in the uterus of essentially all species, yet the function of