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A mutation in amino acid permease AAP6 reduces the amino acid content of the Arabidopsis sieve elements but leaves aphid herbivores unaffected

By E. (Emma) Hunt, Stefano Gattolin, H. J. Newbury, J. S. (Jeffrey S.) Bale, Hua-Ming Tseng, D. A. (David A.) Barrett and J. (Jeremy) Pritchard


The aim of this study was to investigate the role of the amino acid permease gene AAP6 in regulating phloem amino acid composition and then to determine the effects of this altered diet on aphid performance. A genotype of Arabidopsis thaliana (L.) was produced in which the function of the amino acid permease gene AAP6 (At5g49630) was abolished. Plants homozygous for the insertionally inactivated AAP6 gene had a significantly larger mean rosette width than the wild type and a greater number of cauline leaves. Seeds from the aap6 mutant were also significantly larger than those from the wild-type plants. Sieve element (SE) sap was collected by aphid stylectomy and the amino acids derivatized, separated, and quantified using Capillary Electrophoresis with Laser Induced Fluorescence (CE-LIF). In spite of the large variation across samples, the total amino acid concentration of SE sap of the aap6 mutant plants was significantly lower than that of the wild-type plants. The concentrations of lysine, phenylalanine, leucine, and aspartic acid were all significantly lower in concentration in the aap6 mutant plants compared with wild-type plants. This is the first direct demonstration of a physiological role for an amino acid transporter in regulating SE composition in vivo. The amino acid availability in sieve element sap is thought to be the major limiting factor for aphid growth and reproduction. Despite the changes in their diet, the aphid Myzus persicae (Sulzer) displayed only small changes in feeding behaviour on mutant plants when measured using the Electronic Penetration Graph (EPG) technique. Salivation by the aphid into the SE (E1 phase) was increased on mutant plants but there was no significant effect on other feeding EPG behaviours, or in the rate of honeydew production. Consistent with the small effect on aphid feeding behaviour, there was only a small effect of reduced sieve element amino acid concentration on aphid reproduction. The data are discussed in relation to the regulation of phloem composition and the role of phloem amino acids in regulating aphid performance

Topics: QK, SB
Publisher: Oxford University Press
Year: 2010
OAI identifier:

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  12. (2001). ANT1, an aromatic and neutral amino acid transporter in Arabidopsis. doi
  13. (1996). Aphid stylectomy reveals an osmotic step between sieve tube and cortical cells in barley roots. doi
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  17. (1993). Cloning a plant amino acid transporter by functional complementation of a yeast amino acid transport mutant. doi
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  22. (1997). Effects of previous plant infestation on sieve element acceptance by two aphids. doi
  23. (1993). Expression cloning in yeast of a cDNA encoding a broad specificity amino acid permease from Arabidopsis thaliana. doi
  24. (2001). Feeding behaviour of the aphid Rhopalosiphum padi (Hemiptera: Aphididae) on nitrogen and water-stressed barley (Hordeum vulgare) seedlings. doi
  25. (1993). Fine structure of aphid stylet route in plant tissues in correlation with EPG signals. doi
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  27. (2002). High affinity amino acid transporters specifically expressed in xylem parenchyma and developing seeds of Arabidopsis. doi
  28. (2010). Downloaded from
  29. (1997). LHT1, lysine- and histidine-specific amino acid transporter in Arabidopsis. doi
  30. (2002). Loss of the AKT2/3 potassium channel affects sugar loading into the phloem of Arabidopsis. doi
  31. (2002). Low and high affinity amino acid H +-cotransporters for cellular import of neutral and charged amino acids. doi
  32. (1994). Microsampling and measurements of solutes in single cells.
  33. (2007). Molecular sabotage of plant defense by aphid saliva. doi
  34. (2003). Phloem amino acids and the host plant range of the polyphagous aphid, Aphis fabae. doi
  35. (2006). Phloem-sap feeding by animals: problems and solutions. doi
  36. (1998). Plant penetration by pea aphids (Acyrthosiphon pisum) of different plant range. doi
  37. (2003). Reduced amino acid content in transgenic potato tubers due to antisense inhibition of the leaf H +/ amino acid symporter StAAP1. The Plant doi
  38. (1970). Reproduction of the aphid Myzus persicae related to the mineral nutrition of potato plants. doi
  39. (2003). Reproductive response of generalist and specialist aphid morphs with the same genotype to plant secondary compounds and amino acids. doi
  40. (1995). Seed and vascular expression of a high-affinity transporter for cationic amino acids in Arabidopsis. doi
  41. (1977). Simple estimation of intrinsic rates from aphids and tertanyxhid mites.
  42. (2004). Solute is imported to elongating root cells of barley as a pressure driven-flow of solution. doi
  43. (2007). Solute transport in the phloem. doi
  44. (1998). Structure and function of plasma membrane amino acid, oligopeptide and sucrose transporters from higher plants. doi
  45. (1966). Studies on the relations of insect and host plant. III. A comparison of the reproduction of Brevicoryne brassicae and Myzus persicae (Homoptera: Aphididae) on Brussel’s sprout plants supplied with different rates of nitrogen and potassium. doi
  46. (1995). Substrate specificity and expression profile of amino acid transporters (AAPs) in Arabidopsis. doi
  47. (2009). Sucrose transporter1 functions in phloem loading in maize leaves. doi
  48. (2007). The amino acid permease AAP8 is important for early seed development in Arabidopsis thaliana. doi
  49. (2006). The Arabidopsis thaliana/Myzus persicae model system demonstrates that a single gene can influence the interaction between a plant and a sap-feeding insect. doi
  50. (2003). The nutritional physiology of aphids. doi
  51. (1993). Tissue localization of lettuce resistance to the aphid Nasonovia ribisnigri using electrical penetration graphs. doi
  52. (2001). Transporters responsible for the uptake and partitioning of nitrogenous solutes.
  53. (2002). Use of aphid stylectomy and RT-PCR for the detection of transporter mRNAs in sieve elements. doi

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