Aromatic amino acid transporter AAT-9 of caenorhabditis elegans localizes to neurons and muscle cells. Export

@article{citeulike:3317512, abstract = {The C. elegans genome encodes nine homologues of mammalian glycoprotein-associated amino acid transporters. Two of these C. elegans proteins (AAT-1 and -3) have been shown to function as catalytic subunits (light chains) of heteromeric amino acid transporters. These proteins need to associate with a glycoprotein heavy chain subunit (ATG-2) to reach the cell surface in a similar manner to their mammalian homologues. AAT-1 and 3 contain a cysteine residue in the second putative extracellular loop through which a disulfide bridge can form with a heavy chain. In contrast six C. elegans members of this family (AAT-4 to -9) lack such a cysteine residue. We show here that one of these transporter proteins, AAT-9, reaches the cell surface in Xenopus oocytes without an exogenous heavy chain and that it functions as an exchanger of aromatic amino acids. Two-electrode voltage clamp experiments demonstrate that AAT-9 displays a substrate-activated conductance. Immunofluorescence shows that it is expressed close to the pharyngeal bulbs within C. elegans neurons. The selective expression of an aat-9 promoter-GFP construct in several neurons of this region and in wall muscle cells around the mouth supports and extends these localization data. Taken together, the results show that AAT-9 is expressed in excitable cells of the nematode head and pharynx in which it may provide a pathway for aromatic amino acid transport.}, author = {Veljkovic, E. and Bacconi, A. and Stetak, A. and Hajnal, A. and Stasiuk, S. and Skelly, P. J. and Forster, I. and Shoemaker, C. B. and Verrey, F.}, citeulike-article-id = {3317512}, citeulike-linkout-0 = {http://view.ncbi.nlm.nih.gov/pubmed/15364921}, citeulike-linkout-1 = {http://www.hubmed.org/display.cgi?uids=15364921}, citeulike-linkout-2 = {http://www.wormbase.org/db/misc/paper?name=WBPaper00024381}, journal = {J Biol Chem}, keywords = {aat-1, aat-4, aat-9, article, atgp-2, c38c62, c\_elegans, caenorhabditis\_elegans, celegans, elegans, f27c81, nematode, t13a1010, wormbase, y53h1c1}, pages = {49268--49273}, posted-at = {2008-09-22 19:53:17}, priority = {3}, title = {Aromatic amino acid transporter AAT-9 of caenorhabditis elegans localizes to neurons and muscle cells.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/15364921}, volume = {279}, year = {2004} }

TY - JOUR ID - citeulike:3317512 L3 - citeulike-article-id:3317512 N2 - The C. elegans genome encodes nine homologues of mammalian glycoprotein-associated amino acid transporters. Two of these C. elegans proteins (AAT-1 and -3) have been shown to function as catalytic subunits (light chains) of heteromeric amino acid transporters. These proteins need to associate with a glycoprotein heavy chain subunit (ATG-2) to reach the cell surface in a similar manner to their mammalian homologues. AAT-1 and 3 contain a cysteine residue in the second putative extracellular loop through which a disulfide bridge can form with a heavy chain. In contrast six C. elegans members of this family (AAT-4 to -9) lack such a cysteine residue. We show here that one of these transporter proteins, AAT-9, reaches the cell surface in Xenopus oocytes without an exogenous heavy chain and that it functions as an exchanger of aromatic amino acids. Two-electrode voltage clamp experiments demonstrate that AAT-9 displays a substrate-activated conductance. Immunofluorescence shows that it is expressed close to the pharyngeal bulbs within C. elegans neurons. The selective expression of an aat-9 promoter-GFP construct in several neurons of this region and in wall muscle cells around the mouth supports and extends these localization data. Taken together, the results show that AAT-9 is expressed in excitable cells of the nematode head and pharynx in which it may provide a pathway for aromatic amino acid transport. JF - J Biol Chem EP - 49273 TI - Aromatic amino acid transporter AAT-9 of caenorhabditis elegans localizes to neurons and muscle cells. VL - 279 SP - 49268 KW - aat-1 KW - aat-4 KW - aat-9 KW - article KW - atgp-2 KW - c38c62 KW - c_elegans KW - caenorhabditis_elegans KW - celegans KW - elegans KW - f27c81 KW - nematode KW - t13a1010 KW - wormbase KW - y53h1c1 AU - Veljkovic, E AU - Bacconi, A AU - Stetak, A AU - Hajnal, A AU - Stasiuk, S AU - Skelly, PJ AU - Forster, I AU - Shoemaker, CB AU - Verrey, F PY - 2004/// UR - http://view.ncbi.nlm.nih.gov/pubmed/15364921 ER -