On an annual basis, 3.3 million babies will die worldwide due to complications in pregnancy that leads to preterm birth (PTB) or stillbirths. While many of the initiating factors remain to be identified, we know that infection accounts for roughly 20-25% of PTBs in the United States and is the primary cause of PTB in underdeveloped countries. Cervical remodeling - the process by which the cervix is transformed from a closed rigid structure to one that can open to allow passage of a term fetus through the birth canal - is a key component of the birth process that may be disrupted during infections. A better understanding of mechanisms that drive term and infection-mediated preterm cervical remodeling will provide new insights that can be used for the detection and prevention of PTB. The processes that govern cervical remodeling in term or preterm birth are regulated at (1) the transcriptional level by the expression of mRNAs, microRNAs, and long non-coding RNAs (lncRNAs) and (2) the post-transcriptional level by the actions of miRNAs on target mRNAs and ncRNAs. The integration of these mechanisms forms a regulatory circuit that allows finely tuned and carefully coordinated gene expression programs. The identification of the complete transcriptome, as well as clinically relevant interactions between microRNAs and their target mRNAs and lncRNAs in relevant biological models, will provide new insights into the biological mechanisms that mediate premature cervical ripening. The goal of the current study is to apply cutting-edge genomic, bioinformatic, and computational approaches to the study of infection-mediated gene regulation in a mouse model of infection mediated preterm birth, as well as a complementary model of inflammation in the human cervix to establish proof-of-principle for this approach. Specifically, we will use RNA-seq and Ago HITS-CLIP (high-throughput sequencing of RNAs isolated by crosslinking immunoprecipitation of Argonaute) technologies, in conjunction with cell-based gene-specific assays, to identify, confirm, and explore the gene expression programs that regulate infection mediated cervical ripening in these two complimentary models of cervical infection/inflammation. Validation of gene targets identified in this study will suppor the future potential of these approaches to dissect the molecular pathways that regulate processes critical for successful parturition at term and to understand how regulatory circuits go awry in preterm birth.
Understanding the molecular processes that modulate infection-mediated premature cervical remodeling is critical to the identification of therapeutic targets and the development of improved tools for early risk detection. The focus of this application is to apply cutting- edge genomic approaches to validate the potential insights that can be gained through our identification of the complete transcriptome, as well as clinically relevant interactions between microRNAs and their target mRNAs and lncRNAs in two complimentary models of infection/inflammation induced cervical ripening. The knowledge gained from these studies have the potential to (1) provide new ways of thinking about and studying infection-mediated premature cervical remodeling and (2) suggest new ways to proactively diagnose and treat infection-mediated preterm birth.
|Willcockson, Alexandra R; Nandu, Tulip; Liu, Cheuk-Lun et al. (2018) Transcriptome signature identifies distinct cervical pathways induced in lipopolysaccharide-mediated preterm birth. Biol Reprod 98:408-421|