Caenorhabditis elegansBicarbonate Transporter ABTS-1 Is Involved in Arsenite Toxicity and Cholinergic Signaling.

Arsenic poisoning affects millions of people worldwide. Although there is accumulating evidence to suggest that the nervous system is a target of arsenic, relatively little information is known regarding its effects on the nervous system. The effects of arsenite on the nervous system in Caenorhabditis eleganswere investigated in the present study. We found that abts-1, which encodes a Na+-dependent Cl−/HCO3−transporter, is required to protect C. elegansfrom arsenite toxicity. The abts-1::GFPtransgene is primarily expressed in neurons and the hypodermis, but stronger expression was also observed in the pharynx and body wall muscle cells after exposure to arsenite. The steady-state level of ABTS-1 mRNA increased in response to arsenite exposure. We showed that worms lacking abts-1are hypersensitive to the paralytic effects of the cholinesterase inhibitor, aldicarb, and the nicotinic acetylcholine receptor agonist, levamisole. We also showed that arsenite enhanced sensitivity to aldicarb and levamisole in abts-1mutant worms. Our results indicate neuronal effects of arsenite and the ABTS-1 bicarbonate transporter. [ABSTRACT FROM AUTHOR]