Genetic screening and multipotency in rhesus monkey haploid neural progenitor cells

Abstract

Haploid embryonic stem cells (haESCs) have been extensively applied in forward and reverse genetic screening. However, the mammalian haploid somatic cell line is difficult to achieve because of spontaneous diploidization in differentiation. As a non-human primate species, monkeys are widely used in basic and pre-clinical research in which haploid cells are restricted to ESCs. Here, we report that rhesus monkey haESCs in an optimized culture medium showed naïve-state pluripotency and stable haploidy. This model facilitated the derivation of haploid neural progenitor cells (haNPCs), which maintained haploidy and differentiation potential into neurons and glia for a long period in vitro. High-throughput trapping mutations can be efficiently introduced into haNPCs via piggyBac transposons. This system served well in the aim to identify gene targets of neural toxicants via a proof-of-concept experiment. Using CRISPR/Cas9 editing, we confirmed that B4GALT6, from the candidate list, is a resistance gene of A-803467 (a tetrodotoxin-like toxin). This model is the first non-human primate haploid somatic cell line with proliferative ability, multipotency, and an intact genome, thus providing a cellular resource for recessive genetic and potential drug screening.