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Du, T.-Y.

Publications and source records attributed to Du, T.-Y..

4 recordsLinked to original sources

Schizosaccharomyces orthogroup (SOG) resource: a web platform for exploring gene conservation in fission yeasts

The fission yeast Schizosaccharomyces pombe is a prominent model organism widely used to investigate fundamental cellular mechanisms. In addition to S. pombe, the genus Schizosaccharomyces includes six other species--S. octosporus, S. japonicus, S. cryophilus, S. osmophilus, S. lindneri, and S. versatilis. These fission yeast species share a common ancestor from which the genus diversified over more than 200 million years. This extensive evolutionary divergence provides opportunities for comparative genomics. Here, we present the Schizosaccharomyces orthogroup (SOG) resource, a web platform developed from our high-quality genome assemblies, gene annotations, and orthology assignments. Most fission yeast genes are assigned to one of over 5,000 orthogroups. The platform enables users to visualize orthogroup sequence alignments and phylogenetic trees, retrieve coding and flanking sequences, and explore the conservation of local synteny. This resource will benefit researchers focusing on individual genes as well as those investigating gene evolution at broader scales. It is freely accessible at https://www.sogweb.org. TAKE AWAYO_LIThe SOG resource covers all known species of Schizosaccharomyces. C_LIO_LIThe platform is built on high-quality genome assemblies and annotations. C_LIO_LIMost genes are assigned to one of over 5,000 orthogroups. C_LIO_LIUsers can view and explore alignments, phylogenetic trees, and local synteny. C_LIO_LIThis free resource aids functional and evolutionary research. C_LI

genomics↗

Evolutionary persistence and divergence of the tdk killer meiotic driver family

Killer meiotic drivers (KMDs) are selfish genetic elements that achieve super-Mendelian inheritance by selectively eliminating gametes lacking the driver. Although predicted to arise recurrently, KMDs are generally considered evolutionarily ephemeral--going extinct after fixation or host suppression. The identification of tdk1, a single-gene KMD in the fission yeast Schizosaccharomyces pombe, provides a model for studying KMD evolution. Here, we identify two divergent tdk1 homologs (tdk210 and tdk203) from S. cryophilus, a fission yeast species that diverged [~]100 million years ago from S. pombe, as active KMDs. These three KMDs all act via post-germination killing, disrupting chromosome segregation in noncarrier progeny. Notably, they also exhibit striking functional divergences: tdk1, tdk210, and tdk203 are mutually incompatible (showing no cross-resistance), and the latter two act independently of Bdf1/Bdf2--host chromatin proteins required for tdk1 killing. Phylogenetic analyses of the dozens of tdk family genes in Schizosaccharomyces support long-term persistence and rapid evolutionary dynamics of this gene family. Remarkably, homologs in distantly related fungal phyla display genomic and structural similarities to Schizosaccharomyces tdk genes, suggesting a deeply rooted origin of this KMD family in fungi. Our findings reveal that a single KMD family can undergo repeated functional innovation--generating mutually incompatible variants and rewiring host dependencies--while maintaining a conserved killing mode over deep evolutionary time.

evolutionary biology↗

Evolutionary modes of wtf meiotic driver genes in Schizosaccharomyces pombe

Killer meiotic drivers (KMDs) are a class of selfish genetic elements that defy Mendels law and bias transmission in their favor by destroying meiotic progeny that do not carry them. How KMDs evolve is not well understood. In the fission yeast Schizosaccharomyces pombe, the largest gene family, known as the wtf genes, is a KMD family that causes intraspecific hybrid sterility. Here, we investigate how wtf genes evolve using long-read-based genome assemblies of 31 distinct S. pombe natural isolates, which encompass the known genetic diversity of S. pombe. Our analysis, involving nearly 1,000 wtf genes in these isolates, yields a comprehensive portrayal of the intraspecific diversity of wtf genes. Leveraging single-nucleotide polymorphisms in adjacent unique sequences, we pinpoint wtf-gene-containing loci that have recently undergone gene conversion events and infer their pre-gene-conversion state. These events include the revival of wtf pseudogenes, lending support to the notion that gene conversion plays a role in preserving this gene family from extinction. Moreover, our investigation reveals that solo long terminal repeats (LTRs) of retrotransposons, frequently found near wtf genes, can act as recombination arms, influencing the upstream regulatory sequences of wtf genes. Additionally, our exploration of the outer boundaries of wtf genes uncovers a previously unrecognized type of directly oriented repeats flanking wtf genes. These repeats may have facilitated the early expansion of the wtf gene family in S. pombe. Our findings enhance the understanding of the mechanisms influencing the evolution of this KMD gene family.

evolutionary biology↗

Ubiquitination-mediated Golgi-to-endosome sorting determines the poison-antidote duality of wtf meiotic drivers

Killer meiotic drivers (KMDs) skew allele transmission in their favor by killing meiotic progeny not inheriting the driver allele. Despite their widespread presence in eukaryotes, the molecular mechanisms behind their selfish behavior are poorly understood. Here we investigate how the toxin and antidote products of a fission yeast wtf-family KMD gene can act antagonistically. Both the toxin and the antidote are multi-transmembrane proteins, differing only in their N-terminal cytosolic tails. We find that the antidote employs N-terminal PY motifs (Leu/Pro-Pro-X-Tyr) to bind Rsp5/NEDD4 family ubiquitin ligases, which ubiquitinate the antidote. Mutating PY motifs or attaching a deubiquitinating enzyme transforms the antidote into a toxic protein. Ubiquitination promotes the transport of the antidote from the trans-Golgi network to the endosome, thereby preventing it from causing toxicity. A physical interaction between the antidote and the toxin enables the ubiquitinated antidote to translocate the toxin to the endosome and neutralize its toxicity. We propose that post-translational modification-mediated protein localization and/or activity changes may be a common mechanism governing the antagonistic duality of single-gene KMDs.

cell biology↗