Biology subjects

Law, S. T. S.

Publications and source records attributed to Law, S. T. S..

7 recordsLinked to original sources

bioRxiv2025

Single-cell analyses reveal scyphozoan conserved and specific genes contribution during tissue regeneration in two jellyfish

The phylum Cnidaria is the outgroup of Bilateria and includes sea anemones, corals, hydroids, and jellyfish. Cnidarians play crucial ecological roles in marine ecosystems, including the formation of highly diverse and productive coral reefs, and acting as important predator and prey species. Cnidarians are also well known for their remarkable regeneration capacities. Here, we report single-cell RNA sequencing during bell regeneration in two species of scyphozoans or true jellyfish, Aurelia coerulea and Rhopilema esculentum. We delineated 12 cell populations in Aurelia and Rhopilema, and revealed their respective marker genes and enriched gene pathways. Conserved transcription factor Otx and Wnt/ {beta}-catenin signalling pathway genes were identified during regeneration processes. Additionally, we discovered two conserved, sequentially activated modules during regeneration, with stem cells, gastrodermal cells, neural cells, and secretory gland cells modulated in the first phase, followed by cnidocytes in the second phase. Further comparison among cnidarian genomes identified a suite of scyphozoan lineage-specific genes, a subset of which were frequently significantly expressed in cnidocytes in both jellyfish species during the first phase of regeneration. This study reveals key insights into the evolution and contribution of conserved and novel genes to the formation of lineage-specific genetic networks and biological processes.

evolutionary biology↗

bioRxiv2024

Chromosomal-level reference genome and microRNAs of the ricefield flatsedge Cyperus iria

BackgroundGrass-like plants in the Cyperaceae family, commonly known as sedges, have a global distribution and include many economically problematic weeds. The ricefield flatsedge, Cyperus iria, is an aggressive weed in rice crops in Asia. ResultHere, we present a chromosomal-level genome assembly for C. iria (461.2 Mb, scaffold N50 = 7.3 Mbp, 99.6% BUSCO score) providing potential targets for the control of this devastating weed. Based on the genome assembly and transcriptomes of vegetative tissues, 52,574 protein-coding genes were predicted to be encoded. A total of 26 conserved and 75 novel microRNAs, including 9 microRNA clusters, were also annotated. Synteny and microRNA cluster analyses further showed that C. iria had undergone at least one round of whole genome duplication. ConclusionThe genomic resource established in this study sets up a foundation to further address basic and applied questions in the Cyperaceae.

genomics↗

bioRxiv2024

Chromosomal-level genome of fish mint Houttuynia cordata Thunb. (Saururaceae)

Herbaceous flowering plants in the family Saururaceae, or commonly known as the lizards tail family, are native to Southeast Asia and North America. Fish mint Houttuynia cordata is native to Southeast Asia and widely cultivated as culinary herb and medicinal plant in traditional medicine. Here, using a combination of PacBio HiFi long-read sequencing and Omni-C data, we present the chromosomal-level genome assembly of H. cordata (genome size 499.6 Mb). The genome has high sequence contiguity (scaffold N50 = 64.3 Mb) and completeness (BUSCO score of 94.6 %). 40,451 protein coding genes were also predicted using two transcriptomes generated in this study. The fish mint genome provides a valuable resource for further understanding the bioactive compounds and evolution of plants in the Saururaceae more widely.

genomics↗

bioRxiv2024

Genome of tropical bed bug Cimex hemipterus (Cimicidae, Hemiptera) reveals tetraspanin expanded in bed bug ancestor

Cimex species are ectoparasites that exclusively feed on warm-blooded animals such as birds and mammals. Three cimicid species are known to be persistent pests for humans, including the tropical bed bug C. hemipterus, common bed bug C. lectularius, and Eastern bat bug Leptocimex boueti. To date, genomic information is restricted to the common bed bug C. lectularius, which limits understand their biology and to provide controls of bed bug infestations. Here, a chromosomal-level genome assembly of C. hemipterus (495 Mb) containing on 16 pseudochromosomes (scaffold N50 = 34 Mb), together with 9 messenger RNA and small RNA transcriptomes were obtained. Comparison between hemipteran genomes, we found that the tetraspanin superfamily were expanded in the Cimex ancestor. This study provides the first genome assembly for the tropical bed bug C. hemipterus, and offers an unprecedented opportunity to address to questions relating to bed bug infestations, as well as genomic evolution to hemipterans more widely.

genomics↗

bioRxiv2024

Genome assembly of the edible jelly fungus Dacryopinax spathularia (Dacrymycetaceae)

The edible jelly fungus Dacryopinax spathularia (Dacrymycetaceae) is wood-decaying and can be commonly found worldwide. It has also been used in food additives given its ability to synthesize long-chain glycolipids. In this study, we present the genome assembly of D. spathularia using a combination of PacBio HiFi reads and Omni-C data. The genome size of D. spathularia is 29.2 Mb and in high sequence contiguity and completeness, including scaffold N50 of 1.925 Mb and 92.0% BUSCO score, respectively. A total of 11,510 protein-coding genes, and 474.7 kb repeats accounting for 1.62% of the genome, were also predicted. The D. spathularia genome assembly generated in this study provides a valuable resource for understanding their ecology such as wood decaying capability, evolutionary relationships with other fungus, as well as their unique biology and applications in the food industry.

genomics↗

bioRxiv2024

Genome assembly of the rare and endangered Grantham's camellia, Camellia granthamiana

The Granthams camellia (Camellia granthamiana Sealy) is a rare and endangered tea species that is endemic to southern China, and was first discovered in Hong Kong in 1955. Despite its high conservation value, genomic resources of C. granthamiana remain limited. Here, we present a chromosome-scale draft genome of the tetraploid C. granthamiana (2n = 4x = 60) using a combination of PacBio long read sequencing and Omni-C data. The assembled genome size is [~]2.4 Gb with most sequences anchored to 15 pseudochromosomes that resemble a monoploid genome. The genome is of high contiguity, with a scaffold N50 of 139.7 Mb, and high completeness with a 97.8% BUSCO score. Gene model prediction resulted in a total 76,992 protein-coding genes with a BUSCO score of 85.9%. 1.65 Gb of repeat content was annotated, which accounts for 68.48% of the genome. The Granthams camellia genome assembly provides a valuable resource for future investigations on its biology, ecology, phylogenomic relationships with other Camellia species, as well as set up a foundation for further conservation measures.

plant biology↗

bioRxiv2020

Chromosomal-level reference genome of the incense tree Aquilaria sinensis

Trees in the genus Aquilaria (Thymelaeaceae) are known as lign aloes, and are native to the forests of southeast Asia. Lign aloes produce agarwood as an antimicrobial defence. Agarwood has a long history of cultural and medicinal use, and is of considerable commercial value. However, due to habitat destruction and over collection, lign aloes are threatened in the wild. We present a chromosomal-level assembly for Aquilaria sinensis, a lign aloe endemic to China known as the incense tree, based on Illumina short-read, 10X Genomics linked-read, and Hi-C sequencing data. Our 783.8Mbp A. sinensis genome assembly is of high physical contiguity, with a scaffold N50 of 87.6Mbp, and high completeness, with a 95.8% BUSCO score for eudicotyledon genes. We include 17 transcriptomes from various plant tissues, providing a total of 35,965 gene models. We reveal the first complete set of genes involved in sesquiterpenoid production, plant defence, and agarwood production for the genus Aquilaria, including genes involved in the biosynthesis of sesquiterpenoids via the mevalonic acid (MVA), 1-deoxy-D-xylulose-5-phosphate (DXP), and methylerythritol phosphate (MEP) pathways. We perform a detailed repeat content analysis, revealing that transposable elements account for [~]61% of the genome, with major contributions from gypsy-like and copia-like LTR retroelements. We also provide a comparative analysis of repeat content across sequenced species in the order Malvales. Our study reveals the first chromosomal-level genome assembly for a tree in the genus Aquilaria and provides an unprecedented opportunity to address a variety of applied, genomic and evolutionary questions in the Thymelaeaceae more widely.

genomics↗