Bartel Laboratory

The Bartel lab studies small RNAs that regulate eukaryotic gene expression. The main focus is on microRNAs (miRNAs), which are ~22-nt RNAs found in plant and animal cells, where they specify gene repression by base pairing to messages of protein-coding genes. The miRNAs are encoded by unusual genes whose primary transcripts form distinctive hairpin structures from which the miRNAs are processed.

Some students in the lab do full-time computational biology. They use computational approaches to discover new miRNA genes, learn the principles of miRNA target recognition, or place the miRNAs into gene-regulatory networks. Others do part-time or full-time experimental biology and use molecular methods to supplement, validate, and extend the insights gained by the computational studies.

We study RNA catalysts and RNA-mediated cellular processes. With regard to the ability of RNA to catalyze reactions, we want to know the types of reactions that RNA can catalyze and how easy it is for new RNA enzymes (ribozymes) to emerge. Knowledge of the intrinsic catalytic abilities of RNA provides a backdrop for understanding biocatalysis and is critical for evaluating current notions of life's origins and early evolution. Studies often include in vitro selection experiments, which allow us to isolate very rare catalytic molecules from very large libraries of different sequences. For example, we have generated a ribozyme that synthesizes small pieces of RNA, supporting the idea of RNA self-replication in the early evolution of life.

With regard to RNA-mediated cellular processes, we are currently studying endogenous gene silencing mediated by RNA, including targeted mRNA degradation (RNAi), and a class of tiny noncoding RNAs with regulatory roles in eukaryotes (microRNAs). Most recently we have identified hundreds of microRNA genes in animals and plants. We are currently combining biochemical, molecular, genetic, and computational approaches to identify additional genes, explore their roles in regulating eukaryotic gene expression, and determine the molecular mechanisms of their action.