Dareen Almojil

Biotechnology +4

13 Followers 3 FollowingTotal Views

Papers

Middleton Reefs Marine National Nature Reserve and Lord

may be reproduced by any process without prior written permission from the Commonwealth. Requests... more

Download

Population genetic structure of Australian Galapagos reef sharks Carcharhinus galapagensis at Elizabeth and Middleton Reefs Marine National Nature Reserve and Lord Howe Island Marine Park Prepared

Sharks and rays of the Arabian/Persian Gulf

Weak population structure of the Spot‐tail shark Carcharhinus sorrah and the Blacktip shark C. limbatus along the coasts of the Arabian Peninsula, Pakistan, and South Africa

Ecology and Evolution, 2018

The increase in demand for shark meat and fins has placed shark populations worldwide under high ... more The increase in demand for shark meat and fins has placed shark populations worldwide under high fishing pressure. In the Arabian region, the spot‐tail shark Carcharhinus sorrah and the Blacktip shark Carcharhinus limbatus are among the most exploited species. In this study, we investigated the population genetic structure of C. sorrah (n = 327) along the coasts of the Arabian Peninsula and of C. limbatus (n = 525) along the Arabian coasts, Pakistan, and KwaZulu‐Natal, South Africa, using microsatellite markers (15 and 11 loci, respectively). Our findings support weak population structure in both species. Carcharhinus sorrah exhibited a fine structure, subdividing the area into three groups. The first group comprises all samples from Bahrain, the second from the UAE and Yemen, and the third from Oman. Similarly, C. limbatus exhibited population subdivision into three groups. The first group, comprising samples from Bahrain and Kuwait, was highly differentiated from the second and th...

Download

Local ecological knowledge of fisheries charts decline of sharks in data-poor regions

Scientific knowledge is lacking on marine species of economic and conservation importance, hinder... more Scientific knowledge is lacking on marine species of economic and conservation importance, hindering their sustainable management. Local Ecological Knowledge (LEK) has the potential to provide valuable insights on large (spatial and temporal) scales, by drawing on the collective experiences of those who work closely with the taxa of interest. This study explored the status of shark population over time in four countries across eastern and southern Arabia (i.e. Kuwait, Bahrain, Oman and Yemen). Results indicate strong declines, with highly experienced fishermen reporting greater perceived declines (80%) in the abundance of sharks (in general), with mean year of perceived decline starting in the late 1990s to early 2000s. For three specific taxa investigated, hammerhead sharks (e.g. Sphyrna mokarran) had the greatest mean perceived decline (80%), while even the group with the least decline (small carcharhinids) had mean perceived declines of 50%. Management measures are urgently requi...

Male mate choice in the Spot-tail shark Carcharhinus sorrah : are males choosy or opportunistic?

Male mate choice has been documented in different taxa including insects, lizards, fish, birds an... more Male mate choice has been documented in different taxa including insects, lizards, fish, birds and mammals. However, in sharks, male mate choice is not clearly reported but field observations suggest that it is probable. In this study, I tested for evidence of male mating preference of the spot-tail shark Carcharhinus sorrah towards three female traits that are typically associated with female fecundity, these are: (1) body size, (2) parasite burden, and (3) mean heterozygosity. I collected data on heterozy-gosity, age, length and parasite burden of 73 litters of C. sorrah females. I found no association between male mating preference and any of the selected female traits. A possible interpretation is that, given the polygamous mating system of sharks and consequent likelihood of sperm competition, C. sorrah males focus primarily on obtaining fertilization, rather than adjusting their behavior according to potential fitness differences between females. Future research is needed to g...

Metabolome modulation of the host adaptive immunity in human malaria

Nature Metabolism

Host responses to infection with the malaria parasite Plasmodium falciparum vary among individual... more Host responses to infection with the malaria parasite Plasmodium falciparum vary among individuals for reasons that are poorly understood. Here we reveal metabolic perturbations as a consequence of malaria infection in children and identify an immunosuppressive role of endogenous steroid production in the context of P. falciparum infection. We perform metabolomics on matched samples from children from two ethnic groups in West Africa, before and after infection with seasonal malaria. Analysing 306 global metabolomes, we identify 92 parasitaemia-associated metabolites with impact on the host adaptive immune response. Integrative metabolomic and transcriptomic analyses, and causal mediation and moderation analyses, reveal an infection-driven immunosuppressive role of parasitaemia-associated pregnenolone steroids on lymphocyte function and the expression of key immunoregulatory lymphocyte genes in the Gouin ethnic group. In children from the less malaria-susceptible Fulani ethnic group, we observe opposing responses following infection, consistent with the immunosuppressive role of endogenous steroids in malaria. These findings advance our understanding of P. falciparum pathogenesis in humans and identify potential new targets for antimalarial therapeutic interventions.

The Structural, Functional and Evolutionary Impact of Transposable Elements in Eukaryotes

Genes

Transposable elements (TEs) are nearly ubiquitous in eukaryotes. The increase in genomic data, as... more Transposable elements (TEs) are nearly ubiquitous in eukaryotes. The increase in genomic data, as well as progress in genome annotation and molecular biology techniques, have revealed the vast number of ways mobile elements have impacted the evolution of eukaryotes. In addition to being the main cause of difference in haploid genome size, TEs have affected the overall organization of genomes by accumulating preferentially in some genomic regions, by causing structural rearrangements or by modifying the recombination rate. Although the vast majority of insertions is neutral or deleterious, TEs have been an important source of evolutionary novelties and have played a determinant role in the evolution of fundamental biological processes. TEs have been recruited in the regulation of host genes and are implicated in the evolution of regulatory networks. They have also served as a source of protein-coding sequences or even entire genes. The impact of TEs on eukaryotic evolution is only no...

Download

Microsatellite records for volume 8, issue 2

Conservation Genetics Resources, 2016

Extensive genetic population structure in the Indo–West Pacific spot-tail shark, Carcharhinus sorrah

Bulletin of Marine Science -Miami-

Carcharhinus sorrah (Mülle and Henle, 1839) is a coastal pelagic shark of the tropical and subtro... more Carcharhinus sorrah (Mülle and Henle, 1839) is a coastal pelagic shark of the tropical and subtropical Indo–West Pacific, reaching 1.6 m total length. The species is widely harvested in line, net, and trawl fisheries over tropical continental shelves. We investigated mtDNA genetic differentiation in C. sorrah across the majority of the species' range, and examined the importance of six major historical and contemporary biogeographic features in shaping population genetic structure in this species. The present study includes dense sampling for a shark species across the Indo–West Pacific, with 349 specimens sampled from 21 collection locations from the northwestern Indian Ocean, Southeast Asia, New Caledonia, and to southerly distribution limits in Australia. Based on 469 base pairs of the control region, we found extensive genetic population structure, with allopatric lineages confined to Australia, New Caledonia, and the remaining surveyed area. Significant genetic subdivisions...

Download