Leo

Leonardo Valdivia

Assistant professor


LEONARDO.VALDIVIA@UMAYOR.CL


I obtained my PhD with Miguel Allende at Universidad de Chile working on the development of the mechanosensory lateral line system in zebrafish. At that time, I could visit Steve Wilson’s lab in London to participate in a mutagenic screen for isolating novel mutations affecting the development of such system. During the process of screening I became fascinated with the power of the zebrafish genetics but also with the research performed in the English lab regarding eye and brain development. Therefore, for my post-doc I moved to London to join Steve’s lab at UCL where I focused upon studying the function of essential genes for development, growth and differentiation in the zebrafish eye. After this, I returned to Chile to join the Center for Integrative Biology at Universidad Mayor where I opened my Developmental Genetics Lab to keep studying fish eyes.

My research has been recognized with fellowships and awards, including the Best PhD thesis Award by the Chilean Society for Cell Biology in 2012 and the Early Career Stage Scientist Award at the “Genes, Epigenetics and Evolution in Eye Development and Disease” conference in 2014.



Turner KJ, Hoyle J, Valdivia LE, Cerveny KL, Hart W, Mangoli M, Geisler R, Rees M, Houart C, Poole RJ, Wilson SW, Gestri G. 2019. Abrogation of Stem Loop Binding Protein (Slbp) function leads to a failure of cells to transition from proliferation to differentiation, retinal coloboma and midline axon guidance deficits. PLoS One. 2019 Jan 29;14(1):e0211073. doi: 10.1371/journal.pone.0211073. eCollection

Patel A, Hayward JD, Tailor V, Nyanhete R, Ahlfors H, Gabriel C, Jannini TB, Coskun P, Abbou-Rayyah Y, Henderson R, Nischal KK, Islam L, Bitner-Glindzicz M, Hurst J, Valdivia LE, Zanolli M, Moosajee M, Brookes J, Papadopoulos M, Khaw PT, Cullup T, Jenkins L, Dahlmann-Noor A, Sowden JC. 2019. The Oculome panel test: next-generation sequencing to diagnose a diverse range of
genetic developmental eye disorders. Ophthalmology. 2019 Jun;126(6):888-907. doi: 10.1016/j.ophtha.2018.12.050. Epub 2019 Jan 14.

Krasnow, A.M., M.C. Ford, L.E. Valdivia, S.W. Wilson, and D. Attwell. 2018. Regulation of developing myelin sheath elongation by oligodendrocyte calcium transients in vivo. Nat. Neurosci. 21. doi:10.1038/s41593-017-0031-y.

Fuentes, R., Letelier, J., Tajer, B., Valdivia, L.E., Mullins, M.C. (2018) Fishing forward and reverse: Advances in zebrafish phenomics. Mechanisms of Development. 154:296-308.

Valdivia, L.E., D.B. Lamb, W. Horner, C. Wierzbicki, A. Tafessu, A.M. Williams, G. Gestri, A.M. Krasnow, T.S. Vleeshouwer-Neumann, M. Givens, R.M. Young, L.M. Lawrence, H.L. Stickney, T.A. Hawkins, Q.P. Schwarz, F. Cavodeassi, S.W. Wilson, and K.L. Cerveny. 2016. Antagonism between Gdf6a and retinoic acid pathways controls timing of retinal neurogenesis and growth of the eye in zebrafish. Dev. 143. doi:10.1242/dev.130922.

Tuschl, K., E. Meyer, L.E. Valdivia, N. Zhao, C. Dadswell, A. Abdul-Sada, C.Y. Hung, M.A. Simpson, W.K. Chong, T.S. Jacques, R.L. Woltjer, S. Eaton, A. Gregory, L. Sanford, E. Kara, H. Houlden, S.M. Cuno, H. Prokisch, L. Valletta, V. Tiranti, R. Younis, E.R. Maher, J. Spencer, A. Straatman-Iwanowska, P. Gissen, L.A.M. Selim, G. Pintos-Morell, W. Coroleu-Lletget, S.S. Mohammad, S. Yoganathan, R.C. Dale, M. Thomas, J. Rihel, O.A. Bodamer, C.A. Enns, S.J. Hayflick, P.T. Clayton, P.B. Mills, M.A. Kurian, and S.W. Wilson. 2016. Mutations in SLC39A14 disrupt manganese homeostasis and cause childhood-onset parkinsonism-dystonia. Nat. Commun. 7. doi:10.1038/ncomms11601.

Bazin-Lopez, N., L.E. Valdivia, S.W. Wilson, and G. Gestri. 2015. Watching eyes take shape. Curr. Opin. Genet. Dev. 32. doi:10.1016/j.gde.2015.02.004.

Ceci, M.L., C. Mardones-Krsulovic, M. Sánchez, L.E. Valdivia, and M.L. Allende. 2014. Axon-Schwann cell interactions during peripheral nerve regeneration in zebrafish larvae. Neural Dev. 9. doi:10.1186/1749-8104-9-22.

Moro, E., G. Ozhan-Kizil, A. Mongera, D. Beis, C. Wierzbicki, R.M. Young, D. Bournele, A. Domenichini, L.E. Valdivia, L. Lum, C. Chen, J.F. Amatruda, N. Tiso, G. Weidinger, and F. Argenton. 2012. In vivo Wnt signaling tracing through a transgenic biosensor fish reveals novel activity domains. Dev. Biol. 366. doi:10.1016/j.ydbio.2012.03.023.

Valdivia, L.E., R.M. Young, T.A. Hawkins, H.L. Stickney, F. Cavodeassi, Q. Schwarz, L.M. Pullin, R. Villegas, E. Moro, F. Argenton, M.L. Allende, and S.W. Wilson. 2011. Lef1-dependent Wnt/β-catenin signalling drives the proliferative engine that maintains tissue homeostasis during lateral line development. Development. 138. doi:10.1242/dev.062695.

Image_research.png#asset:1621. We study the genetic bases of eye formation
Our goal is to unravel the mechanisms controlling eye growth and retina differentiation. This has biomedical relevance because an imbalance between these processes can lead to developmental eye disorders in humans. We investigate how eyes take shape using the zebrafish as a vertebrate model. These fish have external fertilization, small size, transparency at embryonic stages, and powerful molecular and genetic tools. Such features facilitate the functional study of genes. Previously, in a forward genetic screen we isolated mutants displaying small eyes and we are currently identifying the responsible genetic lesions for these phenotypes. More recently, we are using CRISPR/Cas9 to induce novel mutations and other genetic modifications at specific loci in the zebrafish genome. These complementary approaches will enable us to understand the mechanisms driving cells from a progenitor state towards differentiation in the eye

Name: Support for the formation of international networks between research centers.

Title: A multimodel collaborative network to study development and
function of the nervous system in health and disease.

Sponsor Institution: CONICYT

Responsible Researcher: Felipe Court

Other Researcher: Leonardo Valdivia.

Date of Execution: 2019- 2021

Name: Support for the formation of international networks for researchers at the beginning stage.

Title: Combinación de modelos de pez cebra y Drosophila para resolver la función biológica del gen mab21l2 durante la formación del ojo.

Sponsor Institution: CONICYT

Responsible Researcher: Leonardo Valdivia.

Date of Execution: 2018- 2020

Name: FONDECYT

Title: Genetic analysis of eye growth and the causes of microphthalmia in a vertebrate model: the role of mab21l2

Sponsor Institution: FONDECYT

Responsible Researcher: Leonardo Valdivia

Date of Execution: 2016- 2019

Octavia Santis

Biotechnology of the Universidad Mayor. Lab Manager and technical assistant. Performs specific work of Molecular biology and embryology.

Valeska Mancilla

Bachelor of Marine Science from the Andres Bello University. Responsible for managing the fish nursery (zebrafish and medaka) to achieve the best possible biomass production. She works for the laboratories of Leonardo Valdivia and Joaquin Letelier.

Aaron Villanueva.

Biotechonology student of the Universidad Mayor. Undergraduate thesis in the laboratory. CRISPR/ Cas9 technology.

Cristian Sobarzo:

Biotechnology student of the Universidad Mayor. Undergraduate tester in the laboratory, exploring the relationship between the TGF- -β signaling pathway and one of the favourite genes: mab2112. With analysis of mutants and transgenic reporters, you will dissect this interaction.

National

Felipe Court/Dr. Mario Sanhueza. Centro de Biología Integrativa, Universidad Mayor.

Joaquin Letelier. Centro de Biología Integrativa, Universidad Mayor.

Ricardo Fuentes. Universidad de Concepción.

International

Steve Wilson. University College London, Reino Unido.

Jane Sowden. University College London, Reino Unido.

Richard Poole. University College London, Reino Unido.

Kara Cerveny. Reed College, Estados Unidos.

Paul Frankel y Dr. Margaret Ashcroft. University College London/Cambridge University, Reino Unido.

Juan Ramón Martínez-Morales, CABD, Universidad Pablo Olavide, España.