Transcriptome and metabolome analysis of crGART, a novel cell model of de novo purine synthesis deficiency: Alterations in CD36 expression and activity.

Randall C Mazzarino,Nathan Duval,Marie Zikánová,Guido N Vacano,Terry G Wilkinson,Veronika Baresova,David Patterson,Arun Rishi

doi:10.1371/journal.pone.0247227

Randall C Mazzarino, Nathan Duval + Show 6 more

Open Access

https://doi.org/10.1371/journal.pone.0247227

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Abstract

In humans, GART [phosphoribosylglycinamide formyltransferase (EC 2.1.2.2) / phosphoribosylglycinamide synthetase (EC 6.3.4.13) / phosphoribosylaminoimidazole synthetase (EC 6.3.3.1)] is a trifunctional protein which catalyzes the second, third, and fifth reactions of the ten step de novo purine synthesis (DNPS) pathway. The second step of DNPS is conversion of phosphoribosylamine (5-PRA) to glycineamide ribonucleotide (GAR). 5-PRA is extremely unstable under physiological conditions and is unlikely to accumulate in the absence of GART activity. Recently, a HeLa cell line null mutant for GART was constructed via CRISPR-Cas9 mutagenesis. This cell line, crGART, is an important cellular model of DNPS inactivation that does not accumulate DNPS pathway intermediates. In the current study, we characterized the crGART versus HeLa transcriptomes in purine-supplemented and purine-depleted growth conditions. We observed multiple transcriptome changes and discuss pathways and ontologies particularly relevant to Alzheimer disease and Down syndrome. We selected the Cluster of Differentiation (CD36) gene for initial analysis based on its elevated expression in crGART versus HeLa as well as its high basal expression, high log2 value, and minimal P-value.

Highlights

De novo purine biosynthesis (DNPS) is one of the oldest and most fundamental biochemical pathways [1]
Our results indicate that GART null cells have a large number of differentially expressed genes (DEG) and may have an important role in embryogenesis, neural development, and perhaps special relevance to Alzheimer’s disease (AD) and Down syndrome (DS)
HeLa and crGART cells were cultured in complete-serum media overnight and subsequently cultured in media supplemented with dialyzed-serum (FCM) with or without supplemental adenine

Summary

Introduction

De novo purine biosynthesis (DNPS) is one of the oldest and most fundamental biochemical pathways [1]. Transcriptome and metabolome analysis of crGART, a novel cell model of de novo purine synthesis deficiency

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Conclusion