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Biology subjects

Shi, Z.-X.

Publications and source records attributed to Shi, Z.-X..

3 recordsLinked to original sources

Multiplexed direct RNA sequencing using RB-dRNAseq with RNA barcodes

Nanopore direct RNA sequencing (dRNA-Seq) simultaneously resolves RNA sequences, poly(A) tail lengths, and base modifications at the single-molecule level. Here, we developed RB-dRNAseq, a multiplexed dRNA-Seq method using RNA-barcoded reverse transcription adapters (RTAs) compatible with Oxford Nanopore Technologies (ONT) workflows, enabling highly efficient sample demultiplexing based solely on basecalled sequences. On the RNA004 platform, RB-dRNAseq achieved >99.5% demultiplexing accuracy, with 81% of reads assigned in 6-plex samples. This represents a 16%-24% relative increase in read recovery compared to conventional DNA barcoding methods that rely on basecalling-based demultiplexing. To evaluate the sensitivity of RB-dRNAseq, we performed sequencing with low-input samples, demonstrating that even with 1 ng of total RNA, gene expression (r=0.84) and m6A modification (r=0.91) profiles remained highly consistent with high-input benchmarks. We further explored the feasibility of RB-dRNAseq in ultra-low input scenarios by applying it to mouse zygotes and 2-cell stage embryos. The method successfully captured dynamic shifts in gene isoform expression and multiple RNA modifications (m6A, m5C, pseU, and Inosine) during zygotic genome activation (ZGA), uncovering site-specific regulatory patterns.

genomics↗

Single-cell RNA sequencing uncovers cell-type-specific reprogramming of water-channel and cell-wall genes in PFOA uptake by lettuce root tips

Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants that accumulate in edible crops, posing threats to food safety and human health. Breeding varieties with reduced PFAS accumulation offers a promising mitigation strategy, yet the underlying cellular mechanisms remain elusive. Here, we integrated short- and long-read single-cell RNA sequencing to generate a high-resolution transcriptomic atlas of lettuce (Lactuca sativa L.) root tips, comparing varieties with contrasting perfluorooctanoic acid (PFOA) accumulation capacities. Our analyses uncovered a synergistic mechanism underlying PFOA uptake: up-regulation of aquaporin genes in epidermal and xylem cells, coupled with down-regulation of cell-wall biosynthesis genes specifically in epidermal and xylem. Furthermore, we identified distinct RNA isoforms-including variants with altered coding potential-that may contribute to PFOA transport and deposition through structural modulation of the encoded proteins. This study represents the first application of single-cell sequencing to elucidate the cellular and molecular basis of crop responses to PFOA, providing new insights into pollutant-crop interactions and informing strategies for sustainable agriculture and food safety.

plant biology↗

HIT-scISOseq: High-throughput and High-accuracy Single-cell Full-length Isoform Sequencing for Corneal Epithelium

Single-cell isoform sequencing can reveal transcriptomic dynamics in individual cells invisible to bulk- and single-cell RNA analysis based on short-read sequencing. However, current long-read single-cell sequencing technologies have been limited by low throughput and high error rate. Here we introduce HIT-scISOseq for high-throughput single-cell isoform sequencing. This method was made possible by full-length cDNA capture using biotinylated PCR primers, and by our novel library preparation procedure that combines head-to-tail concatemeric full-length cDNAs into a long SMRTbell insert for high-accuracy PacBio sequencing. HIT-scISOseq yields > 10 million high-accuracy full-length isoforms in a single PacBio Sequel II 8M SMRT Cell, providing > 8 times more data output than the standard single-cell isoform PacBio sequencing protocol. We exemplified HIT-scISOseq by first studying transcriptome profiles of 4,000 normal and 8,000 injured corneal epitheliums from cynomolgus monkeys. We constructed dynamic transcriptome landscapes of known and rare cell types, revealed novel isoforms, and identified injury-related splicing and switching events that are previously not accessible with low throughput isoform sequencing. HIT-scISOseq represents a high-throughput, cost-effective, and technically simple method to accelerate the burgeoning field of long-read single-cell transcriptomics.

genomics↗