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Kexin Li

Publications and source records attributed to Kexin Li.

4 recordsLinked to original sources

Whole-Genome Sequencing Reveals Co-Infection with Bovine Viral Diarrhea Virus, Bovine Enterovirus, and Caprine Parainfluenza Virus Type 3 in a Calf from a Cattle Herd in Xizang, China.

Although mixed viral infections are increasingly recognized as contributors to bovine diarrhea syndrome, diagnosing such co-infections remains challenging, particularly in high-altitude regions where surveillance is limited. In July 2024, a calf presenting with severe diarrhea and respiratory distress was identified on a cattle farm in Linzhi, Xizang, China. Using unbiased whole-genome sequencing (WGS) of the fecal sample, we assembled near-complete genomes of three distinct RNA viruses: two bovine viral diarrhea virus type 1 (BVDV-1) strains (subtypes 1v and 1q, designated BVDV-1/XZ87 and XZ87), one bovine enterovirus (genotype EV-E, designated BEV/XZ87), and one caprine parainfluenza virus type 3 (CPIV3/XZ87). The CPIV3/XZ87 genome exhibited 99.9% nucleotide identity to the goat-derived GS2017-2 strain from Jiangsu, China, raising the possibility of viral spread through livestock trade. Quantitative real-time PCR (RT-qPCR) confirmed the presence of all three pathogens (Ct values: 24.78 for BEV, 25.98 for CPIV3, and 31.28 for BVDV). This study provides the genomic evidence of a triple co-infection involving BVDV-1, BEV, and CPIV3 in Xizang. It illustrates the potential of WGS for unbiased pathogen detection in complex clinical specimens. The near-complete genomes generated here fill critical gaps in the virological surveillance of this epidemiologically under-sampled high-altitude region.

bovine enterovirus

The H3K27me3 reader GmLHP1 impairs Phytophthora sojae resistance by repressing ethylene precursor accumulation in soybean.

Phytophthora root rot, caused by Phytophthora sojae, is a devastating soilborne disease of soybean (Glycine max). However, the epigenetic regulation of soybean responses to P. sojae remains incompletely understood. Here, using genetic, molecular and biochemical approaches, we characterized the functions of LIKE HETEROCHROMATIN PROTEIN 1 (GmLHP1) and its downstream regulatory network. We demonstrated that GmLHP1, as a reader of H3K27me3, negatively regulates soybean resistance to P. sojae. GmLHP1 binds to H3K27me3 peptides in vitro and colocalizes with H3K27me3 marks genome-wide in vivo. The integrated chromatin immunoprecipitation sequencing and RNA sequencing analysis identified the ethylene biosynthesis pathway gene 1-AMINO-CYCLOPROPANE-1-CARBOXYLATE SYNTHASE 18 (GmACS18) as being enriched for H3K27me3 and bound by GmLHP1, leading to its transcriptional downregulation. Notably, GmLHP1 associates with the GmACS18 promoter by directly binding to AATTAA motifs and recognizing H3K27me3 marks. Moreover, GmACS18 enhances defense against P. sojae by accumulating the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC). Further analysis unveiled that recognition of H3K27me3 by GmLHP1 is essential for regulating soybean resistance to P. sojae through repressing GmACS18 transcription and decreasing ACC accumulation. Our findings reveal a novel epigenetic regulatory mechanism in which the H3K27me3 reader GmLHP1 blocks soybean resistance to P. sojae by repressing ethylene precursor ACC accumulation.

ACC accumulation

Oral and gut microbiota profiles in patients with locally advanced rectal cancer with varying responses to neoadjuvant chemoradiotherapy.

Recent research has focused on gut bacteria in colorectal cancer, but the influence of other microbiota, including oral and nonbacterial gut microbiota, on treatment efficacy remains insufficiently explored. This study aimed to investigate their relationship with the efficacy of neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC). Saliva and fecal samples were collected from patients with LARC before treatment. Shotgun metagenomic sequencing was used to profile bacterial, archaeal, eukaryotic, and viral taxonomic groups and to examine oral and gut microbial functions. An artificial intelligence-based prediction model was developed by integrating oral and gut microbiome data with clinical information. Statistical analyses compared diversity and response-associated microbial features between responders and non-responders to nCRT. Response-associated differences were observed in bacterial and nonbacterial taxonomic profiles and in oral and gut microbial functional profiles. In the internal test subset, the integrated analysis yielded an observed AUC of 0.917. Given the small cohort and the exploratory comparison of candidate classifiers, this estimate requires confirmation in larger, independent cohorts. Baseline oral and gut microbiome profiles were associated with response to nCRT. Integrating microbiome and clinical features showed potential for response prediction, but the model remains exploratory and requires validation in larger, independent cohorts before clinical application. Retrospectively registered on 01/08/2026, NCT07346729.

Aged

Aplf/Dna2 variants drive chromosomal fission and accelerate speciation in zokors.

Chromosomal fissions and fusions are common, yet the molecular mechanisms and implications in speciation remain poorly understood. Here, we confirm a fission event in one zokor species through multiple-omics and functional analyses. We traced this event to a mutation in a splicing enhancer of the DNA repair gene Aplf in the fission-bearing species, which caused exon skipping and produced a truncated protein that disrupted DNA repair. An intronic deletion in Dna2, known to facilitate neo-telomere formation when knocked out, reduced gene activity. These variants collectively drove chromosomal fission in this zokor species. The newly formed chromosome became fixed due to carrying essential genes and strong selective pressure. While geographic isolation likely initiated the divergence of this species and the sister one, the fission event and associated decline at the chromosome level in gene flow probably exacerbated the speciation process. Our work elucidates the genetic basis of chromosomal fission and underscores its role in speciation dynamics.

Multiomics