Purine Biosynthesis Enzymes in Hippocampal Neurons

Abstract

Despite reports implicating disrupted purine metabolism in causing a wide spectrum of neurological defects, the mechanistic details of purine biosynthesis in neurons are largely unknown. As an initial step in filling that gap, we examined the expression and subcellular distribution of three purine biosynthesis enzymes (PFAS, PAICS and ATIC) in rat hippocampal neurons. Using immunoblotting and high-resolution light and electron microscopic analysis, we find that all three enzymes are broadly distributed in hippocampal neurons with pools of these enzymes associated with mitochondria. These findings suggest a potential link between purine metabolism and mitochondrial function in neurons and provide an impetus for further studies.

Expression of the purine biosynthetic enzyme phosphoribosyl formylglycinamidine synthase in neurons

“…As observed in differentiated SH-SY5Y neurons, FGAMS did not appear to directly localize within either pre- or post-synaptic compartments, as evidenced by lack of enrichment in regions of pre-synaptic (synaptophysin) and post-synaptic (post-synaptic density 95, PSD-95) staining (Figure 2C–2D). These results corroborate and extend those of the recent publication by Williamson et al . (2017), which examined FGAMS expression in neurons in relation to mitochondria, but did not examine neurofilament or synaptic markers, or present neuronal FGAMS distribution in both young and mature neurons.…”

“…2000). A recent publication has demonstrated localization of FGAMS with mitochondria in primary rat hippocampal neurons (Williamson et al . 2017), corroborating our data in differentiated human SH-SY5Y neurons.…”

“…2012). Williamson et al recently demonstrated the expression of three purine biosynthetic enzymes near mitochondria in rat neurons (Williamson et al . 2017), but their data did not explore the localization of these enzymes relative to synapses.…”

“…2016). A recent study demonstrated co-localization of FGAMS and two other de novo purine biosynthetic enzymes with mitochondria in primary rat neurons and brain tissue (Williamson et al . 2017).…”

Utilizing Optimized Tools to Investigate PTM Crosstalk: Identifying Potential PTM Crosstalk of Acetylated Mitochondrial Proteins

“…The ten protein targets were all predicted to have mitochondria localization according to the mitocarta 2.0 database [ 35 ] and 8 have been validated as mitochondrial localized [ 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ] ( Table 1 ). The majority of these proteins had been previously identified as acetylated by mass spectrometry [ 44 ].…”