Professor, Kavli Institute for Systems Neuroscience
Ph.D. New York University Medical Center
B.A. New College
Research Interests: Cellular and molecular basis of memory.
Overview: What changes in your brain when you learn something? Lesion studies have determined that a highly conserved structure called the hippocampus is required for memory acquisition in mammals, including humans. My laboratory is interested in how neurons in the hippocampus and related brain areas reflect experience. We use two distinct but complementary approaches to this goal: 1) recording neurons from awake, behaving rodents; and 2) generating genetically-modified mice capable of expressing transgenes in particular neuronal cell types relevant to learning and memory. Combining the former with the latter enables the neural analog of the approach used by engineers to investigate electrical circuits: basically, one records from one circuit element (i.e. neuronal cell type) while manipulating the activity of others. In this way we can explore the transformation of information through the circuitry underlying learning and memory.
TU-Tagging: A Method for Identifying Layer-Enriched Neuronal Genes in Developing Mouse Visual Cortex.
eNeuro. 2017 Sep-Oct;4(5):
Authors: Tomorsky J, DeBlander L, Kentros CG, Doe CQ, Niell CM
Thiouracil (TU)-tagging is an intersectional method for covalently labeling newly transcribed RNAs within specific cell types. Cell type specificity is generated through targeted transgenic expression of the enzyme uracil phosphoribosyl transferase (UPRT); temporal specificity is generated through a pulse of the modified uracil analog 4TU. This technique has been applied in mouse using a Cre-dependent UPRT transgene, CA>GFPstop>HA-UPRT, to profile RNAs in endothelial cells, but it remained untested whether 4TU can cross the blood-brain barrier (BBB) or whether this transgene can be used to purify neuronal RNAs. Here, we crossed the CA>GFPstop>HA-UPRT transgenic mouse to a Sepw1-cre line to express UPRT in layer 2/3 of visual cortex or to an Nr5a1-cre line to express UPRT in layer 4 of visual cortex. We purified thiol-tagged mRNA from both genotypes at postnatal day (P)12, as well as from wild-type (WT) mice not expressing UPRT (background control). We found that a comparison of Sepw1-purified RNA to WT or Nr5a1-purified RNA allowed us to identify genes enriched in layer 2/3 of visual cortex. Here, we show that Cre-dependent UPRT expression can be used to purify cell type-specific mRNA from the intact mouse brain and provide the first evidence that 4TU can cross the BBB to label RNA in vivo.
PMID: 29085897 [PubMed - in process]