Late neurogenic events in the developing mouse spinal cord: Identification of a novel subset of embryonic V2 neurons.

PETRACCA, Y.; SARTORETTI, M.; LANUZA, GM.

Huerta Grande, Córdoba

Congreso; XXVI Reunión Anual de la Sociedad Argentina de Investigación en Neurociencias; 2011

Sociedad Argentina de Investigación en Neurociencias.

LATE NEUROGENIC EVENTS IN THE DEVELOPING MOUSE SPINAL CORD: IDENTIFICATION OF A NOVEL SUBSET OF EMBRYONIC V2 NEURONS.   Yanina L. Petracca, Micaela Sartoretti and Guillermo Lanuza. Developmental Neurobiology Laboratory. Fundación Instituto Leloir. Buenos Aires, Argentina. ypetracca@leloir.org.ar   Despite the progress made in understanding the mechanisms in early cell type specification in the developing neural tube, late embryonic neurogenic events have not been deeply studied. In order to identify the fate of late-born cell types in the ventral spinal cord, we performed genetic lineage tracing in the mouse. We found a novel population of cells marked by the expression of the transcription factors Gata2/3 that are distinct to previously characterized interneurons. Our morphological and molecular analyses show that these cells are cerebrospinal fluid-contacting neurons (CSF-cN) of the central canal. BrdU birthdating experiments indicate that CSF-cN progenitors actively divide until ~E14, contrasting to the earlier generation of V2 interneurons (~E10). Additionally, positional analysis with respect to dorso-ventral patterning genes in combination with the analysis of 5 mutant mouse lines, suggest that CSF-cN derived from p2 ventral progenitors. Finally, while the transcription factor Foxn4 is required for the development of early-born V2 neurons, we found that differentiation of CSF-cN is unaffected in Foxn4 mutants. These results suggest that distinct genetic mechanisms govern the genesis of subsets of V2 cells, including CSF-cN, a novel ?late-born? V2 population. Grant sponsors: MINCyT-ANPCyT Argentina (PICT07-1064), NIH-FIRCA (R03 TW008026) and IBRO Return Home Grant.