We are at the beginning of an exciting new era for neuroscience, as our ability to probe neural circuits and their neuronal components is advancing rapidly due to genetic and optogenetic tools. Our research program applies these tools to address fundamental questions about how the same neural circuitry generates different motor patterns, and how such circuits develop and are maintained. We investigate these questions using the Drosophila larva, which has the following advantages:(i) The connectome of the larval motor circuit is near completion, enabling us to identify, at the single-synapse level, the pre and postsynaptic partners of each individual neuron embedded in it. This anatomical map has provided an excellent substrate to study the development, maintenance, and function of larval motor circuits as well as the cell biology of individual neurons embedded within it. (ii) The larval CNS generates multiple motor behaviors that can be studied at the single neuron/single muscle level. Moreover, using the modern optogenetic methods, it is possible to access individual neurons, monitor or alter their activity, and observe the behavioral consequences. (iii) It is also feasible to selectively inactivate or induce ectopic expression of any gene (e.g. those coding for transcription factors) in the neuron of interest, and examine its effect on intrinsic neural properties, morphology, connectivity pattern, and behavioral performance of the animal, thereby linking the gene to development and behavior.

Google Scholar Profile

1. Giachello CNG, Hunter I, Pettini T, Coulson B, Knufer A, Cachero S, Winding M, Zarin AA, Kohsaka H, Fan YN, Nose A, Landgraf M, Baines RA.J. Electrophysiological validation of monosynaptic connectivity between premotor interneurons and the aCC motoneuron in the Drosophila larval CNS. Neurosci. 2022 Jul 20:JN-RM-2463-21. doi: 10.1523/JNEUROSCI.2463-21.2022. Online ahead of print.PMID: 35868863.
2. Hunter I, Coulson B, Zarin AA, Baines RA. The Drosophila Larval Locomotor Circuit Provides a Model to Understand Neural Circuit Development and Function. Front Neural Circuits. 2021 Jul 1;15:684969. doi: 10.3389/fncir.2021.684969. eCollection 2021.PMID: 34276315
3. Mark B, Lai SL, Zarin AA, Manning L, Pollington HQ, Litwin-Kumar A, Cardona A, Truman JW, Doe CQ. A developmental framework linking neurogenesis and circuit formation in the Drosophila CNS. Elife. 2021 May 11;10:e67510. doi: 10.7554/eLife.67510. PMID: 33973523
4. Zarin AA, et al. “A multilayer circuit architecture for the generation of distinct locomotor behaviors in Drosophila.” eLife 8 (2019): e51781.
5. B Mark, SL Lai, Zarin AA, L Manning, A Cardona. The role of lineage, hemilineage and temporal identity in establishing neuronal targeting and connectivity in the Drosophila embryo. – BioRxiv, 2019
6. Zarin AA, B Mark, A Cardona, A Litwin-Kumar, CQ Doe. A Drosophila larval premotor/motor neuron connectome generating two behaviors via distinct spatio-temporal muscle activity. – BioRxiv, 2019
7. Carreira-Rosario, A, Zarin AA, Clark, MQ, Manning, L, Fetter, RD, Cardona, A et al.. MDN brain descending neurons coordinately activate backward and inhibit forward locomotion. Elife. 2018;7 :. doi: 10.7554/eLife.38554. PubMed PMID:30070205 PubMed Central PMC6097840.
8. Clark, MQ, Zarin AA, Carreira-Rosario, A, Doe, CQ. Neural circuits driving larval locomotion in Drosophila. Neural Dev. 2018;13 (1):6. doi: 10.1186/s13064-018-0103-z. PubMed PMID:29673388 PubMed Central PMC5907184.
9. Heckscher, ES, Zarin AA, Faumont, S, Clark, MQ, Manning, L, Fushiki, A et al.. Even-Skipped(+) Interneurons Are Core Components of a Sensorimotor Circuit that Maintains Left-Right Symmetric Muscle Contraction Amplitude. Neuron. 2015;88 (2):314-29. doi: 10.1016/j.neuron.2015.09.009. PubMed PMID:26439528 PubMed Central PMC4619170.
10. Zarin AA, Asadzadeh, J, Hokamp, K, McCartney, D, Yang, L, Bashaw, GJ et al.. A transcription factor network coordinates attraction, repulsion, and adhesion combinatorially to control motor axon pathway selection. Neuron. 2014;81 (6):1297-1311. doi: 10.1016/j.neuron.2014.01.038. PubMed PMID:24560702 PubMed Central PMC4128230.
11. Zarin AA, Asadzadeh, J, Labrador, JP. Transcriptional regulation of guidance at the midline and in motor circuits. Cell. Mol. Life Sci. 2014;71 (3):419-32. doi: 10.1007/s00018-013-1434-x. PubMed PMID:23917723 .
12. Zarin AA, Daly, AC, Hülsmeier, J, Asadzadeh, J, Labrador, JP. A GATA/homeodomain transcriptional code regulates axon guidance through the Unc-5 receptor. Development. 2012;139 (10):1798-805. doi: 10.1242/dev.070656. PubMed PMID:22461564 .
13. Zarin AA, Behmanesh, M, Tavallaei, M, Shohrati, M, Ghanei, M. Overexpression of transforming growth factor (TGF)-beta1 and TGF-beta3 genes in lung of toxic-inhaled patients. Exp. Lung Res. 2010;36 (5):284-91. doi: 10.3109/01902140903578868. PubMed PMID:20497023 .