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Varna Medical Forum

Rostro-caudal gradient in the expression of transcriptional factor SOX2 in the fetal human brain

Meglena Angelova, Stoyan Pavlov, Veselina Mihaleva, Vanya Goranova, Anton Tonchev

Abstract

Transcriptional factor Sox2 is a key component in a network of genes controlling the faith of diverse types of stem and progenitor cells in the developing brain. Its important role in self-renewal and maintenance of multipotency of embryonic neural progenitors is well established in a number of mammalian species. However, the data about the expression and function of Sox2 in the human fetal brain are scarce and controversial. In the present investigation, we studied Sox2 expression and its rostro-caudal dynamics in human telencephalon at 20th gestational week. Using a standard immunofluorescence technique positive cells for this transcriptional factor were visualized. Their numbers and relative portion were determined and compared in specific germinal zones at various levels and in different areas of the telencephalic cortex. When studying Sox2 expression we discovered significant differences in the numbers of positive cells in all three germinal zones (ventricular, inner subventricular and outer subventricular) in rostro-caudal direction. From rostrally to caudally the relative portion of Sox2 positive cells in the ventricular zone did not showed a significant change, in the inner subventricular zone there was a significant reduction and in the outer subventricular zone there was a slight increase. The differences described in the expression of transcriptional factor Sox2 may be of significance for a better understanding of processes related to the development, differentiation and migration of neural stem/progenitor cells in the human telencephalon during fetal neurogenesis in normal and pathological conditions.

Keywords

Sox2; герминативни зони; човешки мозък; 20-та гестационна седмица

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DOI: http://dx.doi.org/10.14748/vmf.v4i1.1222

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