Maximal Expression of the Evolutionarily Conserved Slit2 Gene Promoter Requires Sp1

Abstract

Slit2 is a neural axon guidance and chemorepellent protein that stimulates motility in a variety of cell types. The role of Slit2 in neural development and neoplastic growth and migration has been well established, while the genetic mechanisms underlying regulation of the Slit2 gene have not. We identified the core and proximal promoter of Slit2 by mapping multiple transcriptional start sites, analyzing transcriptional activity, and confirming sequence homology for the Slit2 proximal promoter among a number of species. Deletion series and transient transfection identified the Slit2 proximal promoter as within 399 base pairs upstream of the start of transcription. A crucial region for full expression of the Slit2 proximal promoter lies between 399 base pairs and 296 base pairs upstream of the start of transcription. Computer modeling identified three transcription factor binding consensus sites within this region, of which only site-directed mutagenesis of one of the two identified Sp1 consensus sites inhibited transcriptional activity of the Slit2 proximal promoter (−399 to +253). Bioinformatics analysis of the Slit2 proximal promoter −399 base pair to −296 base pair region shows high sequence conservation over twenty-two species, and that this region follows an expected pattern of sequence divergence through evolution.

HAT cofactor TRRAP modulates microtubule dynamics via SP1 signaling to prevent neurodegeneration

“…Here we show that Trrap-HAT is upstream of Sp1 and has a specific regulatory role in the Sp1-mediated transcription. Although Sp1 has been reported to bind to the promoter of some genes in neural cells, such as Slit2 ( Saunders et al, 2016 ), P2 × 7 ( García-Huerta et al, 2012 ), and Reelin ( Chen et al, 2007 ), it has not been linked directly with neural development and degeneration. Our transcriptome analyses reveal that many neurological processes are indeed regulated by Sp1 downstream targets, many of which are connected with microtubule dynamics (see Figure 3D , Figure 3—figure supplement 2g , Source data 1A ).…”

Runs of Homozygosity as Footprints of Selection in the Norik of Muran Horse Genome

“…The SLIK2 gene is a neural axon guidance and chemorepellent protein that stimulates motility in a variety of cell types. In mammals, the SLIT family has a role in the proper development of the central nervous system, and organs including the lung, kidney, and mammary gland (Saunders et al, 2016). Cerro-Herreros et al (2018) confirmed that the MIR218-1 is one of the factors which downregulates MBNL proteins in this cell line, responsible for the neuromuscular disease myotonic dystrophy type 1.…”

Beyond HAT Adaptor: TRRAP Liaisons with Sp1-Mediated Transcription

“…Despite the controversy, Sp1 has been shown, in neural model studies, to bind to the promoters of neural genes, e.g., Slit2 [75], P2X7 [76], and Reelin [77]. Our transcriptome studies identified various neurological processes that are regulated by Sp1 downstream targets [29].…”