Olfactory-Immune Interface

Our findings that the developing and adult olfactory sensory system is inexorably linked to the developing blood-lymphatic vasculature system and immune system (Palominos, M.P., Candia, D., and Whitlock, K.E., 2021; Palominos, M.P., Candia, D., Torres-Paz, J., and Whitlock, K.E., submitted) led us to investigate the relationship between the development of glia, neuroendocrine cells, sustentacular cells, and immune cells. We are investigating not only how these classes of cell types interact during development and in the adult animal, but also whether cells move between the peripheral and central olfactory sensory system in both the developing and adult animal.

Neuroendocrine

Recently we have shown that zebrafish lack the gene encoding gonadotropin releasing hormone 1 (gnrh1) the conserved hormone controlling reproduction in vertebrates (Whitlock et al., 2019), and the gene loss is not a result of domestication (selective pressures on laboratory strains). We proposed (Whitlock et al., 2019) that Phoenixin (PNX), a novel protein highly conserved from humans to zebrafish, is a potential replacement for GnRH in zebrafish. Subsequently we have shown that pnx gene is expressed in juvenile and adult zebrafish (Ceriani et al., 2020).

New model for olfactory sensory system development

In contrast to the model where the olfactory organ (OO) is secondarily induced from the ectoderm, we have shown that the OO and olfactory bulb precursors develop from continuous neural ectoderm within the early neural plate (Whitlock, 2008; Torres-Paz and Whitlock, 2014; Torres-Paz et al., 2020), thus suggesting that the olfactory epithelia are a continuum of the CNS much like the visual system where the retina develops from the neural tube.

Outreach

Ciencia Al Tiro (Science Immediately) is an Outreach program Dr. Whitlock developed in 2008 to encourage interest in science and technology. Our goal is to contribute to the betterment of Chile by confronting the deep educational inequality that leaves many young people without a viable future. We have developed books (“La alegria de la Ciencia“, Dec 2014; “La alegria de los Sentidos”, in preparation), as well as educational videos. For more information see: www.cienciaaltiro.cl

Applied Science

Dr. Whitlock is certified in solar thermal design and Aquaponic Systems and has developed Aquaponics and energy efficient technologies in Chile. Years of working with salmon and then zebrafish have proved invaluable to developing recirculating energy efficient systems for Aquaponics. See more at Ciencia Que Pesca: El futuro es saber (Science that grabs you: the future is knowledge) www.cienciaquepesca.cl

• Torres-Paz J, Ceriani R, Whitlock KE. (2026). Bridging cells: Potential crosstalk between the peripheral and central olfactory sensory system. Differentiation. 149:100961. doi: 10.1016/j.diff.2026.100961.
  Image from this paper selected for Cover of Differentiation
• Farlora R, Bustos P, Tine EM, Jeria E, Eapen A, Pillai P, Pino J, Brown DI, Whitlock K. (2026) Effects of neem extract on Artemia franciscana: Insights from high-throughput transcriptomics and phenotypic analysis. PLoS One.  21(8):e0348463. doi: 10.1371/journal.pone.0348463.
• Tine EM, Pinto-Borguero I, Aguirre-Campos C, Escobar M, Fuentes R, Ewer J, Whitlock KE. (2025). The olfactory organ is a site for neuroendocrine modulation of reproduction in zebrafish. bioRxiv 2025.07.07.663467; doi:  10.1101/2025.07.07.663467
• Whitlock KE and Palominos MF (2022). The Olfactory Tract: Basis for Future Evolution in Response to Rapidly Changing Ecological Niches. Front. Neuroanatomy, 17:1153062 doi: 10.3389/fnana.2022.831602. Invited Review
• Palominos MF, Calfun C, Nardocci G, Candia D, Torres-Paz J and Whitlock KE (2022). The olfactory organ is a unique site for resident neutrophils in the brain. Front Immunol.  13:881702. doi: 10.3389/fimmu.2022.881702
• Ceriani R and Whitlock KE (2021). Gonadotropin releasing hormone (GnRH) triggers neurogenesis in the hypothalamus of adult zebrafish. Int. J Mol Sci., May 31;22(11):5926, doi: 10.3390/ijms22115926.
• Palominos M and Whitlock KE (2021) The olfactory organ is populated by neutrophils and macrophages during early development. Front. Cell Dev. Biol., 18 January 2021, doi.org/10.3389/fcell.2020.604030
• Ceriani R, Calfun C and Whitlock KE (2020).  phoenixin(smim20), a gene coding for a novel reproductive ligand, is expressed in the brain of developing and adult zebrafish.  Gene Expr Patterns. Dec 29;39:119164. doi: 10.1016/j.gep.2020.119164.
• Torres-Paz J, Tine EM and Whitlock KE (2020). Dissecting the neural divide: A continuous neurectoderm gives rise to both the olfactory placode and olfactory bulb. International Journal of Developmental Biology,
• Whitlock KE, Postlethwait J and Ewer J (2019) Neuroendocrinology of reproduction: Is gonadotropin-releasing hormone (GnRH) dispensable? Frontiers in Neuroendocrinology, Feb 22. pii: S0091-3022(19)30008-1.
• Cortes-Campos C, Letelier J, Ceriani R and Whitlock KE (2015). Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH) neurons. Biol Open. Jul 24. pii: bio.010447.
• Torres-Paz J and Whitlock KE (2014). Olfactory sensory system develops from coordinated movements within the neural plate. Dev Dyn. Dec;243(12):1619-31.
• Boric K, Orio P, Viéville T and Whitlock KE (2013). Quantitative analysis of cell migration using optical flow. PLoS One. Jul 31;8(7).
• Harden MV, Pereiro L, Ramialison M, Wittbrodt J, Prasad MK, McCallion AS, and Whitlock KE (2012). Close association of olfactory placode precursors and cranial neural crest cells does not predestine cell mixing. Dev Dyn, 241(7): 1143-54
• Calfún C, Dominguez C, Perez-Acle T and Whitlock KE (2016). Changes in olfactory receptor expression are correlated with odor exposure during early development in the zebrafish (Danio rerio). Chem Senses. May;41(4):301-12.
• Stephenson JF, Partridge JC and Whitlock KE (2012) Food and conspecific chemical cues modify zebrafish, Danio rerio, visual behaviour. Zebrafish, Jun;9(2):68-73.
• Stephenson JF, Whitlock KE, Partridge JC (2011) Zebrafish Preference for Light or Dark Is Dependent on Ambient Light Levels and Olfactory Stimulation. Zebrafish, Mar;8(1):17-22.

Books Science Education

• Whitlock KE. and Ciencia al Tiro (2014) La alegria de la Ciencia. Impreso en Chile: Andros Impresores, Santiago. ISBN 978-956-358-304-5
• Bayo A, Flores V, Jaffé Y, Rojas C and Whitlock KE (2020) Bestiario Astromarino. Editorial Catalonia