Dr. Mollie Meffert is an associate professor of biological chemistry and neuroscience at the Johns Hopkins University School of Medicine. Her research focuses on the regulation of neuronal gene expression in health and disease.
Dr. Meffert received her undergraduate degree from Stanford University. She also earned her MD/Ph.D in neuroscience from Stanford University. She completed a postdoctoral fellowship at California Institute of Technology. Dr. Meffert joined the Johns Hopkins faculty in 2004.
The Meffert lab studies mechanisms underlying enduring changes in brain function. We are interested in understanding how programs of gene expression are coordinated and maintained to produce changes in synaptic, neuronal, and cognitive function. Rather than concentrating on single genes, our research is particularly focused on understanding the upstream processes that allow neuronal stimuli to synchronously orchestrate both up and down-regulation of the many genes required to mediate changes in growth and excitation.
Our laboratory recently elucidated a mechanism responsible for pro-growth programs of protein synthesis in which activity-dependent regulation of microRNA (miRNA) production governs the selection of gene targets for protein synthesis. An RNA-binding protein, Lin28, is one activity-responsive factor that promotes pro-growth protein synthesis by downregulating only select miRNAs (e.g. Let-7 ‘tumor suppressor’ miRNAs), which repress pro-growth genes. In neurons, pro-growth mRNA targets of the Let-7 miRNAs include mRNA for proteins involved in excitatory synaptic function, with examples being AMPA receptor subunits (GluA1), CaMKIIa, Homer, BDNF, and TrkB. Ongoing investigations in our laboratory are aimed at further exploration of the importance of miRNA biogenesis in determining rapid and specific changes in the neuronal and synaptic proteome and the in vivo roles of these pathways in healthy and dysregulated brain function.
Dr. Meffert’s work has been recognized with a number of awards including the March of Dimes research scholar, a Simons Foundation Autism Research Initiative award, the Alfred P. Sloan Research Fellow Award, and the Sontag Foundation Distinguished Scientist Award.