Professor John Calarco

John Calarco

Assistant Professor


St. George (downtown)

CSB Appointment


Research Areas

Animal Biology, Bioinformatics / Computational Biology, Developmental Biology, Genetics / Genomics, Molecular Biology, Neurobiology, Systems Biology


Ph.D. University of Toronto, 2011
B.Sc. University of Toronto, 2005

Titles and Honors

Medicine by Design Investigator
Canada Research Chair (Tier II) in Neuronal RNA Biology

Primary Undergraduate Department

Cell & Systems Biology

Graduate Programs

Cell & Systems Biology

Research Description

A major goal of our lab is to better understand the role of post-transcriptional gene regulation in the development, differentiation, and function of the nervous system. The nervous system provides an attractive model to study the mechanism and role of cell-type specific gene regulation because it is composed of diverse neuronal cells that require customized regulatory programs to achieve specialized functions. One research area in my group will focus on understanding the mechanisms and function of alternative splicing in the developing and mature nervous system using both mammalian stem cells and C. elegans. Through the process of alternative splicing, multiple messenger RNAs can be generated from single precursor transcripts. The evolution of alternative splicing has greatly contributed to the diversification of metazoan transcriptomes, and in some species can generate up to an order of magnitude greater number of transcript isoforms than the corresponding repertoire of protein-coding genes. We pursue these problems using a combination of biochemistry, cell biology, molecular genetics, and genome-wide analyses. Additionally, several ongoing projects are directing our research towards investigating the role of other layers of co- and post-transcriptional gene regulation in nervous system development and function.

Contact Information

Office Phone: 416-978-5766
Office: RW 513A
Lab: RW 511
Lab Phone: 416-946-7785

Mailing Address

Department of Cell & Systems Biology
University of Toronto
25 Harbord St.
Toronto, ON M5S 3G5

Visit lab’s website

Recent News

Calarco Lab receives Connaught Award to map RNA binding proteins in the nervous system

Professor John Calarco has been granted a Connaught New Researcher Award to publish a detailed atlas of RNA binding proteins (RBPs), key regulators…

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CSB Year in Review: Top Stories of 2020

As the year comes to a close, we look back on the achievements of students, staff, and faculty in the Cell and Systems Biology Department. Here are…

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Splicing and remixing coded cellular messages reveals new controls on nervous system development.

The Calarco lab in Cell & Systems Biology at U of T has unveiled the signals that direct how RNA messages are remixed within the diverse organs…

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Global regulatory features of alternative splicing across tissues and within the nervous system of C. elegans

Koterniak B, Pilaka PP, Gracida X, Schneider L, Pritišanac I, Zhang Y, Calarco JA
2020, Genome Research, 10.1101/gr.267328.120

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Splicing in a single neuron is coordinately controlled by RNA binding proteins and transcription factors

Thompson M, Bixby R, Dalton R, Vandenburg A, Calarco JA, Norris AD
2019, eLife, 10.7554/eLife.46726

Recurrent noncoding U1 snRNA mutations drive cryptic splicing in SHH medulloblastoma

Suzuki H, Kumar SA, Shuai S, Diaz-Navarro A, Gutierrez-Fernandez A, De Antonellis P, Cavalli FMG, Juraschka K, Farooq H, Shibahara I, Vladoiu MC, Zhang J, Abeysundara N, Przelicki D, Skowron P, Gauer N, Luu B, Daniels C, Wu X, Forget A, Momin A, Wang J, Dong W, Kim S, Grajkowska WA, Jouvet A, Fèvre-Montange M, Garrè ML, Nageswara Rao AA, Giannini C, Kros JM, French PJ, Jabado N, Ng H, Poon WS, Eberhart CG, Pollack IF, Olson JM, Weiss WA, Kumabe T, López-Aguilar E, Lach B, Massimino M, Van Meir EG, Rubin JB, Vibhakar R, Chambless LB, Kijima N, Klekner A, Bognár L, Chan JA, Faria CC, Ragoussis J, Pfister SM, Goldenberg A, Wechsler-Reya RJ, Bailey SD, Garzia L, Morrissy AS, Marra MA, Huang X, Malkin D, Ayrault O, Ramaswamy V, Puente XS, Calarco JA, Stein L, Taylor MD
2019, Nature, 10.1038/s41586-019-1650-0

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Synthetic Genetic Interaction (CRISPR-SGI) Profiling in Caenorhabditis elegans.

Calarco JA, Norris AD
2018, Bio-protocol, 8, 29552597

The UBR-1 ubiquitin ligase regulates glutamate metabolism to generate coordinated motor pattern in Caenorhabditis elegans

Copenhaver GP, Chitturi J, Hung W, Rahman AMA, Wu M, Lim MA, Calarco J, Baran R, Huang X, Dennis JW, Zhen M
2018, PLOS Genetics, 10.1371/journal.pgen.1007303

Genome-wide CRISPR-Cas9 Interrogation of Splicing Networks Reveals a Mechanism for Recognition of Autism-Misregulated Neuronal Microexons

Gonatopoulos-Pournatzis T, Wu M, Braunschweig U, Roth J, Han H, Best AJ, Raj B, Aregger M, O’Hanlon D, Ellis JD, Calarco JA, Moffat J, Gingras A, Blencowe BJ
2018, Molecular Cell, 10.1016/j.molcel.2018.10.008

Imaging whole nervous systems: insights into behavior from worms to fish

Calarco JA, Samuel ADT
2018, Nature Methods, 10.1038/s41592-018-0276-8

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An Elongin-Cullin-SOCS Box Complex Regulates Stress-Induced Serotonergic Neuromodulation.

Gracida X, Dion MF, Harris G, Zhang Y, Calarco JA
2017, Cell reports, 21, 3089-3101, 29241538

CRISPR-mediated genetic interaction profiling identifies RNA binding proteins controlling metazoan fitness.

Norris AD, Gracida X, Calarco JA
2017, eLife, 6, 28718764

Cell type-specific transcriptome profiling in C. elegans using the Translating Ribosome Affinity Purification technique.

Gracida X, Calarco JA
2017, Methods (San Diego, Calif.), 126, 130-137, 28648677

Serotonin-dependent kinetics of feeding bursts underlie a graded response to food availability in C. elegans.

Lee KS, Iwanir S, Kopito RB, Scholz M, Calarco JA, Biron D, Levine E
2017, Nature communications, 8, 14221, 28145493

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Neuroendocrine modulation sustains the forward motor state.

Lim MA, Chitturi J, Laskova V, Meng J, Findeis D, Wiekenberg A, Mulcahy B, Luo L, Li Y, Lu Y, Hung W, Qu Y, Ho CY, Holmyard D, Ji N, McWhirter R, Samuel AD, Miller DM, Schnabel R, Calarco JA, Zhen M
2016, eLife, 5, 27855782

Regulation of Tissue-Specific Alternative Splicing: C. elegans as a Model System.

Gracida X, Norris AD, Calarco JA
2016, Advances in experimental medicine and biology, 907, 229-61, 27256389

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Efficient Genome Editing in Caenorhabditis elegans with a Toolkit of Dual-Marker Selection Cassettes.

Norris AD, Kim HM, Colaiácovo MP, Calarco JA
2015, Genetics, 201, 449-58, 26232410

Creating Genome Modifications in C. elegans Using the CRISPR/Cas9 System.

Calarco JA, Friedland AE
2015, Methods in molecular biology (Clifton, N.J.), 1327, 59-74, 26423968

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EOL-1, the homolog of the mammalian Dom3Z, regulates olfactory learning in C. elegans.

Shen Y, Zhang J, Calarco JA, Zhang Y
2014, The Journal of neuroscience : the official journal of the Society for Neuroscience, 34, 13364-70, 25274815

A pair of RNA-binding proteins controls networks of splicing events contributing to specialization of neural cell types.

Norris AD, Gao S, Norris ML, Ray D, Ramani AK, Fraser AG, Morris Q, Hughes TR, Zhen M, Calarco JA
2014, Molecular cell, 54, 946-59, 24910101

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Heritable genome editing in C. elegans via a CRISPR-Cas9 system.

Friedland AE, Tzur YB, Esvelt KM, Colaiácovo MP, Church GM, Calarco JA
2013, Nature methods, 10, 741-3, 23817069

‘Cryptic’ exons reveal some of their secrets.

Calarco JA
2013, eLife, 2, e00476, 23358458

Heritable Custom Genomic Modifications in Caenorhabditis elegans via a CRISPR–Cas9 System

Tzur YB, Friedland AE, Nadarajan S, Church GM, Calarco JA, Colaiácovo MP
2013, Genetics, doi:10.1534/genetics.113.156075

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Emerging Roles of Alternative Pre-mRNA Splicing Regulation in Neuronal Development and Function.

Norris AD, Calarco JA
2012, Frontiers in neuroscience, 6, 122, 22936897

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