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Biology subjects

Chui, A. P. Y.

Publications and source records attributed to Chui, A. P. Y..

3 recordsLinked to original sources

Evolutionary Genomics Guides Scalable Coral Probiotics for Climate Resilience

A universal bottleneck limiting probiotic efficacy in medicine, aquaculture, agriculture, and wildlife conservation is uncertain long-term colonization, necessitating repeated administration. We present an evolution-guided framework for probiotic identification based on genomic hallmarks of emerging host dependency, including widespread pseudogenization and insertion sequence proliferation driving genomic restructuring. Applied to coral reefs, we screened over 1,200 coral-associated bacterial isolates and identified Ruegeria MC10 as exhibiting these signatures. Its presence was associated with increased thermal tolerance of a model cnidarian. Following nursery application, MC10 persisted in reef corals for an 8-month monitoring period through a natural bleaching event, improving color retention and retaining algal photosynthesis performance. This work establishes a predictive, scalable pipeline for selecting persistent probiotics, directly addressing a central constraint on microbiome-based interventions across host systems.

microbiology↗

Proximity and current alignment drives fertilisation success in a broadcast-spawning coral

As coral populations decline under climate change and other stressors, surviving corals will become increasingly isolated. While Allee effects that reduce gamete encounters and fertilisation success may lead to reproductive and recruitment failure, the critical population densities and distances between individuals required to maintain viable populations remains uncertain. Here, we investigate the links between colony isolation and fertilisation patterns using an experimentally manipulated patch of the broadcast spawning tabular coral, Acropora hyacinthus. Corals were arranged in a clustered radial design, with colonies arranged at increasing distances radiating downstream from a central spawning aggregation. Fertilisation and paternity assignment analyses were used to examine the influence of parental distance, current alignment, colony size, and genetic relatedness. Fertilisation success declined sharply with increasing distance among corals, and paternity assignments indicated most parents were located within 3 m of each other, underscoring the importance of colony proximity. Additionally, fertilisation success was highest for colonies positioned downstream of the central cluster, and 84% of sequenced progeny were sired by colonies located directly upstream. Simulations of natural reef spatial population distributions projected onto a virtual grid, incorporating empirically derived parentage distances, indicated that populations remained well-mixed at typical adult densities in nearby reefs. However, as densities decreased to 1 colony per 100 m-2 (i.e. 0.01 colonieslllm-2), reproductive isolation and the formation of patchy breeding units became prevalent. Overall, our findings highlight that the spatial arrangement and isolation of corals on reefs, and subsequent Allee effects on fertilisation, can jeopardise the reproductive success of broadcast spawning corals. Conservation efforts are needed to help maintain viable coral populations and successful reproductive aggregations for degraded reef systems.

ecology↗

Chromosomal-level genome assembly of the long-spined sea urchin Diadema setosum (Leske, 1778)

The long-spined sea urchin Diadema setosum is an algal and coral feeder widely distributed in the Indo-Pacific and can cause severe bioerosion on the reef community. Nevertheless, the lack of genomic information has hindered the study its ecology and evolution. Here, we report the chromosomal-level genome (885.8 Mb) of the long-spined sea urchin D. setosum using a combination of PacBio long-read sequencing and Omni-C scaffolding technology. The assembled genome contained scaffold N50 length of 38.3 Mb, 98.1 % of BUSCO (Geno, metazoa_odb10) genes, and with 98.6% of the sequences anchored to 22 pseudo-molecules/chromosomes. A total of 27,478 genes including 23,030 protein-coding genes were annotated. The high-quality genome of D. setosum presented here provides a significant resource for further understanding on the ecological and evolutionary studies of this coral reef associated sea urchin.

genomics↗