“Centro Interdisciplinario de Neurociencia de Valparaíso”.
Research Area: Genetic and Developmental Neuroscience.
Professor Kate Whitlock.
Ph.D. in Neuroscience. Instituto de Neurociencias de Alicante, Spain (2013).
Master in Science. Universiteit Maastricht, Holland (2006).
Bachelor in Psychology. Universiteit Maastricht, Holland (2005).
E-mail: isabel.benjumeda at cinv.cl
Teléfono: (56) 32 2508103
Fax: (56)-(32)-250 1111
Address: Centro Interdisciplinario de Neurociencia de Valparaíso.
Facultad de Ciencias, Universidad de Valparaíso.
Gran Bretaña 1111. Playa Ancha. Valparaíso. Chile.
I did my PhD at the “Instituto de Neurociencias de Alicante” under the supervision of Luis Martinez Otero and Eloisa Herrera. During my thesis I studied the relative contribution of molecular guidance cues and retinal spontaneous activity to retinocollicular map formation using mice as a model system. To do so I used both calcium recordings in the developing retina in vivo and in utero electroporation to block spontaneous activity in retinal ganglion cells and to alter the expression of EphA receptors in order to investigate the effects of these manipulations in the formation of the retinocollicular map. Contrary to previous studies in vitro, our results showed that, although spontaneous activity is essential for the proper arborization of retinal axons in their termination zone of the superior colliculus, it is dispensable for the activation of EphA/ephrinA signaling and therefore for topography. This work has been recently published in the “Journal of Neuroscience”:
Benjumeda I, Escalante A, Law C, Morales D, Chauvin G, Muça G, Coca Y, Márquez J, López-Bendito G, Kania A, Martínez L, Herrera E. (2013)Uncoupling of EphA/ephrinA signaling and spontaneous activity in neural circuit wiring. J Neurosci. 33(46):18208-18.
In addition to this during my PhD I did a short term fellowship in the lab of Dr. Macknik at the “Barrow Neurological Institute” in Phoenix, Arizona, recording calcium waves in vivo in the retina of the neonatal mouse. Calcium waves have been previously recorded in retinal explants systems but not in vivo systems. Surprisingly, although we found a clear correlation between calcium transients from neighboring retinal ganglion cells, our results differed from previous findings obtained in vitro showing calcium retinal waves. This work will be submitted soon.
During this Postdoc at Dr. Whitlocks´s lab, we aim to achieve an integrated approach that combines genetic, physiological and behavioral methods in order to understand how sensory stimuli (odorants) experienced during early development affect neural activity and olfactory receptor expression underlying the resulting adult behaviors. To do so, we will use a genetically encoded calcium indicator (Akerboom et al., 2012; Wyart and Del Bene, 2011; Muto and Kawakami, 2011, Muto et al., 2013) driven by an olfactory neuron specific promoter to assay olfactory responses in fish raised in different odor environments. We will first characterize the onset of neural activity in the peripheral olfactory sensory system recording calcium transients, as they provide a good indirect measure of neural activity. With this baseline we will then manipulate odor environment and assay the resulting neural activity to analyze whether the activity patterns of these neurons in response to different olfactory environments are plastic during development.
Changing to zebrafish has the enormous advantage of providing a shorter development period and a broader sample size, with the plus that larvae and juveniles are transparent and can be imaged in vivo at any developmental stage. Therefore, this model is ideal to investigate the mechanisms underlying the development, plasticity and function of the zebrafish olfactory system in vivo.
- Benjumeda I, Escalante A, Law C, Morales D, Chauvin G, Muça G, Coca Y, Márquez J, López-Bendito G, Kania A, Martínez L, Herrera E. (2013)Uncoupling of EphA/ephrinA signaling and spontaneous activity in neural circuit wiring. J Neurosci. 33(46):18208-18.
- Benjumeda I, Molano-Mazón M, Martinez LM (2014) Flowers and weeds: cell-type specific pruning in the developing visual thalamus. BMC Biol, 2014, 12: 3