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Leomil, L.

Publications and source records attributed to Leomil, L..

2 recordsLinked to original sources

The draft genome of the invasive coral Tubastraea sp.

Corals have been attracting huge attention due to the impact of climate change and ocean acidification on reef formation and resilience. Nevertheless, some coral species have been spreading very fast, replacing native species and affecting local biodiversity. Despite some focal efforts to understand the biology of these organisms, they remain understudied at the molecular level. This knowledge gap hinders the development of cost-effective strategies for management of invasive species. Here, we present the first Tubastraea sp. genome in one of the most comprehensive biological studies of a coral, that includes morphology, flow cytometry, karyotyping, transcriptomics, genomics, and phylogeny. The Tubastraea sp. genome is organized in 23 chromosome pairs and has 1.4 Gb making it the largest coral and Cnidaria genome sequenced to date. The hybrid assembly using short and long-reads has a N50 of 180,044 pb, 12,320 contigs and high completeness estimated as 91.6% of BUSCO complete genes. We inferred that almost half of the genome consists of repetitive elements, mostly interspersed repeats. Gene content was estimated as about 94,000, a high number that warrants deeper scrutiny. The Tubastraea sp. genome is a fundamental study which promises to provide insights not only about the genetic basis for the extreme invasiveness of this particular coral species, but to understand the adaptation flaws of some reef corals in the face of anthropic-induced environmental disturbances. We expect the data generated in this study will foster the development of efficient technologies for the management of corals species, whether invasive or threatened.

genomics

Emergence of the East-Central-South-African genotype of Chikungunya virus in Brazil and the city of Rio de Janeiro may have occurred years before surveillance detection

Brazil, which is hyperendemic for dengue virus (DENV), has had recent Zika (ZIKV) and (CHIKV) Chikungunya virus outbreaks. Since March 2016, CHIKV is the arbovirus infection most frequently diagnosed in Rio de Janeiro. In the analysis of 1835 syndromic patients, screened by real time RT-PCR, 56.4% of the cases were attributed to CHIKV, 29.6% to ZIKV, and 14.1% to DENV-4. Sequence analyses of CHIKV from sixteen samples revealed that the East-Central-South-African (ECSA) genotype of CHIKV has been circulating in Brazil since 2013 [95% bayesian credible interval (BCI): 03/2012-10/2013], almost a year before it was detected by arbovirus surveillance program. Brazilian cases are related to Central African Republic sequences from 1980s. To the best of our knowledge, given the available sequence published here and elsewhere, the ECSA genotype was likely introduced to Rio de Janeiro early on 2014 (02/2014; BCI: 07/2013-08/2014) through a single event, after primary circulation in the Bahia state at the Northestern Brazil in the previous year. The observation that the ECSA genotype of CHIKV was circulating undetected underscores the need for improvements in molecular methods for viral surveillance.

genomics