Control de la expresión génica en centros neuronales que controlan el balance energético por el factor de transcripción Isl1

CAMARANO AC; CHASELON D; RUBINSTEIN M; DE SOUZA FS

San Miguel del Monte, Buenos Aires

Jornada; I Jornada Científica: Los mecanismos neuronales que controlan el apetito; 2018

IMBICE-Conicet, La Plata

The hypothalamus is a brain region that regulates several basic homeostatic processes including reproducion, metabolism, energy balance, circadian rhythms, the response to stress and several behaviours. Its high anatomical complexity and location in the ventral forebrain has made it a difficult region to study, but the recent availability of gene expression atlases of the hypothalamus has helped to create a framework to study how the different neuronal types in this structure carry out their differentiation programmes. One of the transcription factors expressed during hypothalamic development is Islet-1 (Isl1). This member of the LIM-homeodomain family has been shown to regulate cell fate specification in multiple tissues and species, in particular the spinal cord, pancreas and heart. In the hypothalamus, Isl1 has a role in regulating gene expression of some neuronal populations of the arcuate nucleus, but its role in other hypothalamic nuclei has not been described yet. With the aim of exploring this topic, we have used immunofluorescence to create a map of Isl1 expression pattern in several timepoints in the developing mouse hypothalamus. Our results show that Isl1 is expressed in an extense area in the early hypothalamus and that it later concentrates in compact areas and nuclei, such as the arcuate nucleus (ARC), subparaventricular area (SPa), anterior hypothalamus (AH), periventricular nucleus (PeVN), the dorsomedial nucleus (DMN), lateral hypothalamic area (LHA), the thalamic zona incerta (ZI) and the retrothalamic nucleus (RTN). With the purpose of elucidating the function that Isl1 exerts in the hypothalamus, we are employing a conditional knockout model which allows for the inactivation of the Isl1 gene at specific timepoints during embryonic development. Our research will shed light on the genetics of neuronal differentiation within the mammalian hypothalamus.