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Abruzzi, K. C.

Publications and source records attributed to Abruzzi, K. C..

2 recordsLinked to original sources

Comparison of TRIBE and STAMP for identifying targets of RNA binding proteins in human and Drosophila cells

RNA binding proteins (RBPs) perform a myriad of functions and are implicated in numerous neurological diseases. To identify the targets of RBPs in small numbers of cells, we developed TRIBE, in which the catalytic domain of the RNA editing enzyme ADAR (ADARcd) is fused to a RBP. When the RBP binds to a mRNA, ADAR catalyzes A to G modifications in the target mRNA that can be easily identified in standard RNA-sequencing. In STAMP, the concept is the same except the ADARcd is replaced by the RNA editing enzyme APOBEC. Here we compared the two enzymes fused to the RBP TDP-43 in human cells. Although they both identified TDP-43 target mRNAs, combining the two methods more successfully identified high confidence targets. We also assayed the two enzymes in Drosophila cells: RBP-APOBEC fusions generated only low numbers of editing sites, comparable to the level of control editing. This was true for two different RBPs, Hrp48 and Thor (Drosophila EIF4E-BP), indicating that TRIBE performed better in Drosophila.

molecular biology↗

A transcriptomic taxonomy of Drosophila circadian neurons around the clock

Many different functions are regulated by circadian rhythms, including those orchestrated by discrete clock neurons within animal brains. To comprehensively characterize and assign cell identity to the 75 pairs of Drosophila circadian neurons, we optimized a single cell RNA sequencing method and assayed clock neuron gene expression at different times of day. The data identify at least 17 clock neuron categories with striking spatial regulation of gene expression. Transcription factor regulation is prominent and likely contributes to the robust circadian oscillation of many transcripts, including those that encode cell-surface proteins previously shown to be important for cell recognition and synapse formation during development. We suggest that these molecules orchestrate the temporal regulation of synapse formation and/or strength. The many other clock-regulated genes also constitute an important resource for future mechanistic and functional studies between clock neurons and/or for temporal signaling to circuits elsewhere in the fly brain.

neuroscience↗