The larval midgut of the hymenopteran parasitoid Aphidius ervi accomplishes a large transport of nutrients from the lumen to the haemocoel, providing most of the organic molecules necessary for rapid insect development. l-amino acids in general, and leucine in particular, are efficiently accumulated in the larval body. We show here that the intact midgut of early 3rd instar larvae incubated in vitro can take up [3H]l-leucine from the basolateral side of the epithelium by transporters insensitive to the presence of monovalent cations. When the midgut is opened and the apical membrane of the absorbing epithelial cells is exposed to the medium containing radiolabelled leucine, a sodium-dependent uptake of the amino acid becomes apparent, disclosing the presence of a symport mechanism. Inhibition experiments of leucine uptake by a 100-fold excess of different amino acids, selected according to the properties of their side chain, revealed that this apical sodium-dependent mechanism is a broad spectrum transport system with a specialization for the absorption of aliphatic amino acids, that can also transfer glutamine and proline, but not phenylalanine, lysine and arginine. Altogether the experimental results obtained with intact- and open-gut preparations suggest that leucine transport across the basolateral membrane is mediated by both an uniporter and an obligatory amino acid exchange mechanism. © 2009 Elsevier Ltd. All rights reserved

Fiandra, L., Caccia, S., Giordana, B., Casartelli, M. (2010). Leucine transport by the larval midgut of the parasitoid Aphidius ervi (Hymenoptera). JOURNAL OF INSECT PHYSIOLOGY, 56(2), 165-169 [10.1016/j.jinsphys.2009.09.015].

Leucine transport by the larval midgut of the parasitoid Aphidius ervi (Hymenoptera)

Fiandra, L.
Primo
;
2010

Abstract

The larval midgut of the hymenopteran parasitoid Aphidius ervi accomplishes a large transport of nutrients from the lumen to the haemocoel, providing most of the organic molecules necessary for rapid insect development. l-amino acids in general, and leucine in particular, are efficiently accumulated in the larval body. We show here that the intact midgut of early 3rd instar larvae incubated in vitro can take up [3H]l-leucine from the basolateral side of the epithelium by transporters insensitive to the presence of monovalent cations. When the midgut is opened and the apical membrane of the absorbing epithelial cells is exposed to the medium containing radiolabelled leucine, a sodium-dependent uptake of the amino acid becomes apparent, disclosing the presence of a symport mechanism. Inhibition experiments of leucine uptake by a 100-fold excess of different amino acids, selected according to the properties of their side chain, revealed that this apical sodium-dependent mechanism is a broad spectrum transport system with a specialization for the absorption of aliphatic amino acids, that can also transfer glutamine and proline, but not phenylalanine, lysine and arginine. Altogether the experimental results obtained with intact- and open-gut preparations suggest that leucine transport across the basolateral membrane is mediated by both an uniporter and an obligatory amino acid exchange mechanism. © 2009 Elsevier Ltd. All rights reserved
Articolo in rivista - Articolo scientifico
Aphidius ervi; Apical Na; +; /amino acid-coupled symport; Hymenoptera; Larval midgut; Leucine uptake;
English
2010
56
2
165
169
none
Fiandra, L., Caccia, S., Giordana, B., Casartelli, M. (2010). Leucine transport by the larval midgut of the parasitoid Aphidius ervi (Hymenoptera). JOURNAL OF INSECT PHYSIOLOGY, 56(2), 165-169 [10.1016/j.jinsphys.2009.09.015].
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/218161
Citazioni
  • Scopus 4
  • ???jsp.display-item.citation.isi??? 4
Social impact