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Rozzi, R.

Publications and source records attributed to Rozzi, R..

2 recordsLinked to original sources

Draft genome of the lowland anoa (Bubalus depressicornis) and comparison with buffalo genome assemblies (Bovidae, Bubalina)

Genomic data for wild species of the genus Bubalus (Asian buffaloes) are still lacking while several whole genomes are currently available for domestic water buffaloes. To address this, we sequenced the genome of a wild endangered dwarf buffalo, the lowland anoa (Bubalus depressicornis), produced a draft genome assembly, and made comparison to published buffalo genomes. The lowland anoa genome assembly was 2.56 Gbp long and contained 103,135 contigs, the longest contig being 337.39 kbp long. N50 and L50 values were 38.73 kbp and 19.83 kbp, respectively, mean coverage was 44x and GC content was 41.74%. Two strategies were adopted to evaluate genome completeness: (i) determination of genomic features with de novo and homology-based predictions using annotations of chromosome-level genome assembly of the river buffalo, and (ii) employment of benchmarking against universal single-copy orthologs (BUSCO). Homology-based predictions identified 94.51% complete and 3.65% partial genomic features. De novo gene predictions identified 32,393 genes, representing 97.14% of the references annotated genes, whilst BUSCO search against the mammalian orthologues database identified 71.1% complete, 11.7% fragmented and 17.2% missing orthologues, indicating a good level of completeness for downstream analyses. Repeat analyses indicated that the lowland anoa genome contains 42.12% of repetitive regions. The genome assembly of the lowland anoa is expected to contribute to comparative genome analyses among bovid species.

genomics↗

Plant longevity, drought and island isolation favoured rampant evolutionary transitions towards insular woodiness

Insular woodiness (IW)--the evolutionary transition from herbaceousness towards woodiness on islands--is one of the most iconic features of island floras. Since pioneering work by Darwin and Wallace, five IW drivers have been proposed: (i) favourable aseasonal climate and (ii) lack of large native herbivores promote plant longevity that (iii) results in prolonged flowering favouring outcrossing. Alternatively, (iv) competition for sunlight requires taller and stronger stems, and (v) drought favours woodiness to safeguard root-to-shoot water transport. However, information on the occurrence of IW is fragmented, hampering tests of these potential drivers. Here, we identify 1,097 insular woody species (IWS) on 375 islands, and infer at least 175 evolutionary transitions on 31 archipelagos, concentrated in six angiosperm families. Structural equation models reveal that the IWS richness on oceanic islands correlates with aseasonal favourable climate, followed by increased drought and island isolation (approximating competition). When continental islands are included, reduced herbivory pressure by large native mammals, increased drought and island isolation are most relevant. The repeated evolution of IW opens promising avenues to disentangle the variation in gene regulatory networks triggering wood formation, and emphasize individual archipelagos as laboratories of evolution, where similar environmental conditions replicate convergent evolution of similar traits.

evolutionary biology↗