Glial enriched gene expression profiling identifies novel factors regulating the proliferation of specific glial subtypes in the Drosophila brain.
Bottom Line: Analysis of the differentially regulated genes in these tissues shows that the expression of known glial genes is significantly increased in both cases.Conversely, the expression of neuronal genes is significantly decreased.These studies provide new insight into the genes and molecular pathways that regulate the proliferation of specific glial subtypes in the Drosophila post-embryonic brain.
Affiliation: Wolfson Centre for Age-Related Diseases, King's College London, Guy's Campus, London SE1 1UL, UK.Show MeSH
Mentions: We have recently shown that the proliferation of two glial subtypes in the Drosophila post-embryonic brain is regulated through the concerted action of the FGF and InR/mTOR pathways. Cortex glia require FGF signalling and the InR, but not downstream components of the InR/mTOR pathway, whereas perineurial glia require both FGF and InR signalling pathways for proliferation. Pan-glial activation of either pathway causes glial overproliferation (Fig. 1B,C). However, specific glial sub-types respond differently to the expression of each receptor. The majority of superficial glia in larval brains from animals overexpressing an activated form of the FGF receptor (HtlACT) in glia expressed both the pan-glial protein Repo and pointedP2 (PntP2), a marker of cortex glia (Fig. 1E,E'). By contrast, glial-specific overexpression of the InR resulted in the proliferation of Repo expressing, but not PntP2 expressing glia (Fig. 1F,F'). These data suggest that these two receptors promote glial proliferation, but that the glial subtypes that proliferate are partially distinct.
Affiliation: Wolfson Centre for Age-Related Diseases, King's College London, Guy's Campus, London SE1 1UL, UK.