bioRxiv Science⌕ Search

bioRxiv · 10.1101/2024.11.23.624830

In situ Membrane Protein Expression by Efficient Recruitment of mRNA to the Membranes of Synthetic Cells

Abstract

The synthesis of artificial cells is crucial for understanding the origins of life. In synthetic cells, however, the absence of membrane-bound organelles and auxiliary proteins severely limits the efficient expression and precise localization of membrane proteins using cell-free expression systems. Here we introduce a robust method that significantly enhances membrane protein synthesis by recruiting mRNA to phospholipid membranes. This is achieved through the use of cholesterol-modified, single-stranded DNA that anchors to the membrane and pairs with the mRNAs untranslated region. This strategic placement facilitates the assembly of protein expression machinery, promoting direct co-translational folding at the membrane. Our approach not only ensures correct protein topology and functionality but also demonstrates broad applicability for the in situ expression of various membrane proteins. It effectively addresses the challenges of membrane protein localization and assembly in synthetic cells, showcasing its versatility for synthesizing a wide array of membrane proteins.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Fu, H., Ma, L., Xu, C., Li, J., Sun, Y., Tao, Y., Wang, H., Hu, S., Fu, M., Zheng, H., Liu, C., Ye, F., Qiao, Y., Li, M., Lu, Y.. 2024-11-23. In situ Membrane Protein Expression by Efficient Recruitment of mRNA to the Membranes of Synthetic Cells. https://doi.org/10.1101/2024.11.23.624830

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Coupled enzyme discovery, evolution and synthetic yeast chassis adaptation for microbial biopolymer valorisation

The valorisation of biological polymers requires microbial systems that can both access recalcitrant substrates and convert the resulting carbon into useful products. Although microbial genome and metagenome resources provide an expanding reservoir of candidate depolymerizing and modifying enzymes, most discovery workflows remain disconnected from enzyme optimisation and host adaptation. Here we present a coupled sequence-based enzyme discovery, enzyme evolution and synthetic yeast chassis adaptation strategy for microbial biopolymer valorisation. Focusing on laccases for the depolymerisation of lignin as a proof of concept, we combine sequence data mining for enzyme discovery, modular yeast surface display for functional screening, directed evolution for enzyme optimisation and synthetic yeast genome diversification for chassis improvement. In our study, surface display enabled functional benchmarking and recovery of improved laccase variants and synthetic-genome-enabled diversification provided a route to explore host configurations that influence display and enzyme performance. By integrating enzyme-level and chassis-level optimisation, this framework addresses a central bottleneck in converting microbial biodiversity by computational sequence repository mining into deployable biomanufacturing systems. Our results establish laccases as tractable entry points for oxidative biopolymer conversion and provide a generalizable platform for engineering yeast systems for sustainable carbon valorisation.

synthetic biology↗

Multichromatic Dynamic Control of Multi-Membered Microbial Consortia Compositions for Chemical Production

Engineered microbial consortia offer a promising strategy for chemical production by distributing specialized functions among microbial strains, reducing metabolic burden, facilitating modular pathway optimization, reducing toxicity, and increasing strain stability. However, differences in growth rates can destabilize population composition, compromising productivity and limiting their applicability. Here, we developed a multichromatic optogenetic Toxin-Antitoxin (optogeneticTA) platform for dynamic control of Escherichia coli consortia of up to four members using blue, red, and near-infrared light and darkness. By varying light intensities or pulses, we precisely program and dynamically modulate the population composition of two-, three-, and four-membered consortia. We further developed a modular mathematical framework that captures and predicts population dynamics of these optogenetically controlled co-cultures. Applying dynamic control to a two-membered engineered consortium increased phenol production by ~69% relative to unregulated consortia. These results establish a programmable platform for stabilizing and dynamically optimizing microbial consortia, with potential applications across microbial biomanufacturing.

synthetic biology↗

Reassessing the contribution of the histone H3 tail to KRAB-DNMT3L-mediated epigenetic silencing

Neumann et al. introduced CHARM, a compact epigenetic silencer in which a histone H3 tail fused to DNMT3L was proposed to recruit and stimulate endogenous DNMT3A, enabling durable gene repression without a fused DNMT3A catalytic domain. Here, we evaluated the contribution of the H3 tail in independent reporter and endogenous-gene contexts. In an SNRPN reporter system, a KRAB-DNMT3L-dCas9 construct lacking the H3 tail displayed silencing kinetics comparable to CRISPRcharm Kv2, and mutating the critical H3K4 residue to alanine in CRISPRcharm Kv2 did not compromise this silencing. Similarly, after transient delivery of editor mRNAs to HEK293T cells, CRISPRcharm Kv2 did not consistently outperform the corresponding H3-tail-free construct at three endogenous loci, and mutating the critical H3K4 residue to alanine in CRISPRcharm Kv2 did not compromise this activity. These observations suggest that the engineered H3 tail does not confer a general functional advantage within the KRAB-DNMT3L-dCas9 architecture under the conditions tested.

synthetic biology↗