Biology subjects

wu, j.

Publications and source records attributed to wu, j..

4 recordsLinked to original sources

bioRxiv2026

A cis-regulatory variant in ASIP causes gray coat color in the donkey

BackgroundGray is one of the relatively rare coat colors in donkeys. The Hetian Gray donkey is a distinctive indigenous breed from the Xinjiang Uygur Autonomous Region of Northwestern China, characterized by progressive hair depigmentation with aging while retaining dark skin pigmentation. However, the genetic basis underlying this unique gray coat color phenotype remains unclear. ResultsTo elucidate the genetic basis, we conducted whole-genome resequencing of Gray and non-Gray donkeys. Genome-wide selection signature analyses identified a candidate region on chromosome 15. Subsequent fine-mapping using mass spectrometry-based genotyping of 42 loci refined the candidate interval and revealed a SNP within intron 2 of the ASIP gene, located in a genomic fragment with highly similar sequences, showing complete association with the gray coat color. Association analysis in an expanded population further confirmed a strong correlation between this variant and the gray phenotype. Gene expression analyses also supported the role of ASIP in regulating pigmentation in donkeys. ConclusionsThese findings identify a genetic determinant of gray coat color in donkeys and provide new insights into the molecular mechanisms underlying age-related depigmentation in domestic animals.

genomics↗

bioRxiv2025

Telomere-to-telomere gap-free genome assembly of a male donkey and the identification of novel SVs associated with functional genes

Previous assemblies of the donkey genome remain with gaps and structural errors, and a complete donkey genome will greatly facilitate genetic research related to donkeys. In the present study, a 2.78-Gb telomere-to-telomere gap-free donkey genome (CAU_T2T_donkey) was assembled, including a 29.78-Mb Y chromosome, aided by ONT and trio-binning approach. CAU_T2T_donkey corrected the structural errors of previous assemblies and added a total of 153.8-Mb previously unresolved regions and 354 genes to the reference genome EquAss-T2T_v2. We identified a 1.9-Mb PAR on CAU_T2T_donkey-chromosome Y, and added 17.1Mb regions and 75 new genes to the chromosome Y of the previous reference genome ASM1607732v2. Multi-copy genes, such as TSPY, L1RE, ETY, HSFY, and ETSTY were also identified in CAU_T2T_donkey-chromosome Y. Totally 6 types of repetitive sequences in centromeric regions were identified, and the features of the centromeric regions were revealed, and satellite-free centromeres were identified. We aligned HiFi long-read sequences of donkeys from six breeds against CAU_T2T_donkey and identified SVs in previously unresolved regions, and some of the novel SVs were located in functional genes, such as AOX1 (Chr4:DEL61), ASIC2 (Chr13:INS954), and Twist2 (Chr19:DEL98).

genomics↗

bioRxiv2022

Dissecting the genetic basis of the heterosis of Y900, an elite super-hybrid rice

Y900 is one of the top hybrid rice varieties with a yield exceeding 15 t/hm2. To dissect the mechanism of heterosis, the male parent line R900 and female parent line Y58S were sequenced using long-read and Hi-C technology. High-quality reference genomes of sizes of 396.41 Mb and 398.24 Mb were obtained for R900 and Y58S, respectively. Genome-wide variations between the parents were systematically identified, including 1,367,758 SNPs and 299,149 Indels. No megabase level structural variations exist. >75% of genes exhibited variation between the two parents. Compared with other two-line hybrids sharing the same female parent, the Geng/japonica-type genetic components from different male parents showed an increasing trend from phase 2-4 super-hybrid rice; Transcriptome analysis revealed that additive and dominance effects are the main genetic effects that constitute the heterosis of Y900. Allele-specific expression patterns and expression regulation patterns are quite dynamic in different tissues. For young panicle tissues, cis-regulation is dominant, while trans-regulation is more popular in leaf issues. Overdominance is more likely regulated by the trans-regulation mechanism. The differential gene expression and regulation pattern are closely related to Geng/japonica introgression. Additionally, R900 contained several excellent japonica haplotypes, such as NAL1, OsSPL13, Ghd8, OsBRI1, and DTH2, which make a good complement to Y58S. The fine tune mechanism through dynamic expression or regulation pattern change, especially on some key functional genes, is the base for heterosis.

plant biology↗

bioRxiv2022

The nanoCUT&RUN technique visualizes telomeric chromatin in Drosophila

Advances in genomic technology led to a more focused pattern for the distribution of chromosomal proteins and a better understanding of their functions. The recent development of the CUT&RUN technique marks one of the important such advances. Here we develop a modified CUT&RUN technique that we termed nanoCUT&RUN, in which a high affinity nanobody to GFP is used to bring micrococcal nuclease to the binding sites of GFP-tagged chromatin proteins. Subsequent activation of the nuclease cleaves the chromatin, and sequencing of released DNA identifies binding sites. We show that nanoCUT&RUN efficiently produces high quality data for the TRL transcription factor in Drosophila embryos, and distinguishes binding sites specific between two TRL isoforms. We further show that nanoCUT&RUN dissects the distributions of the HipHop and HOAP telomere capping proteins, and uncovers unexpected binding of telomeric proteins at centromeres. nanoCUT&RUN can be readily applied to any system in which a chromatin protein of interest, or its isoforms, carries the GFP tag.

genetics↗