Arsenic transport by zebrafish aquaglyceroporinsReportar como inadecuado

Arsenic transport by zebrafish aquaglyceroporins - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

BMC Molecular Biology

, 10:104

First Online: 25 November 2009Received: 22 May 2009Accepted: 25 November 2009


BackgroundArsenic is one of the most ubiquitous toxins and endangers the health of tens of millions of humans worldwide. It is a mainly a water-borne contaminant. Inorganic trivalent arsenic As is one of the major species that exists environmentally. The transport of As has been studied in microbes, plants and mammals. Members of the aquaglyceroporin family have been shown to actively conduct As and its organic metabolite, monomethylarsenite MAs. However, the transport of As and MAs in in any fish species has not been characterized.

ResultsIn this study, five members of the aquaglyceroporin family from zebrafish Danio rerio were cloned, and their ability to transport water, glycerol, and trivalent arsenicals As and MAs and antimonite Sb was investigated. Genes for at least seven aquaglyceroporins have been annotated in the zebrafish genome project. Here, five genes which are close homologues to human AQP3, AQP9 and AQP10 were cloned from a zebrafish cDNA preparation. These genes were named aqp3, aqp3l, aqp9a, aqp9b and aqp10 according to their similarities to the corresponding human AQPs. Expression of aqp9a, aqp9b, aqp3, aqp3l and aqp10 in multiple zebrafish organs were examined by RT-PCR. Our results demonstrated that these aquaglyceroporins exhibited different tissue expression. They are all detected in more than one tissue. The ability of these five aquaglyceroporins to transport water, glycerol and the metalloids arsenic and antimony was examined following expression in oocytes from Xenopus leavis. Each of these channels showed substantial glycerol transport at equivalent rates. These aquaglyceroporins also facilitate uptake of inorganic As, MAs and Sb. Arsenic accumulation in fish larvae and in different tissues from adult zebrafish was studied following short-term arsenic exposure. The results showed that liver is the major organ of arsenic accumulation; other tissues such as gill, eye, heart, intestine muscle and skin also exhibited significant ability to accumulate arsenic. The zebrafish larvae also accumulate considerable amounts of arsenic.

ConclusionThis is the first molecular identification of fish arsenite transport systems and we propose that the extensive expression of the fish aquaglyceroporins and their ability to transport metalloids suggests that aquaglyceroporins are the major pathways for arsenic accumulation in a variety of zebrafish tissues. Uptake is one important step of arsenic metabolism. Our results will contribute to a new understanding of aquatic arsenic metabolism and will support the use of zebrafish as a new model system to study arsenic associated human diseases.






TMAOtrimethylarsine oxide



ICP-MSinductively coupled plasma mass spectrometer

dpfdays post fertilization

hpfhours post fertilization

ORFopen reading frame.

Electronic supplementary materialThe online version of this article doi:10.1186-1471-2199-10-104 contains supplementary material, which is available to authorized users.

Download fulltext PDF

Autor: Mohamad Hamdi - Marco A Sanchez - Lauren C Beene - Qianyong Liu - Scott M Landfear - Barry P Rosen - Zijuan Liu


Documentos relacionados