Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle
The H+-coupled peptide transporter 1 (PepT1) belongs to SoLute Carrier family 15 (SLC15A1) and is responsible for the absorption of di/tripeptides in enterocytes. Beside its nutritional role, it has been hypothesized that PepT1 functions as a transceptor, i.e. a peptide sensor/transporter involved i...
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ftunivsalento:oai:iris.unisalento.it:11587/443453 2024-02-11T10:08:19+01:00 Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle F. Vacca A. Gomes R. Cinquetti K. Murashita F. Imperiali A. Barca T. Verri I. Rønnestad E. Bossi Vacca, F. Gomes, A. Cinquetti, R. Murashita, K. Imperiali, F. Barca, A. Verri, T. Rønnestad, I. Bossi, E. 2018 STAMPA http://hdl.handle.net/11587/443453 eng eng The Physiological Society country:GBR place:London ispartofbook:Europhysiology 2018 Europhysiology 2018 volume:41 http://hdl.handle.net/11587/443453 info:eu-repo/semantics/conferenceObject 2018 ftunivsalento 2024-01-17T17:43:24Z The H+-coupled peptide transporter 1 (PepT1) belongs to SoLute Carrier family 15 (SLC15A1) and is responsible for the absorption of di/tripeptides in enterocytes. Beside its nutritional role, it has been hypothesized that PepT1 functions as a transceptor, i.e. a peptide sensor/transporter involved in gut hormone release from entero-endocrine cell(s)1, 2. Studying the role of PepT1 in peptide absorption in the gut is relevant for the direct relation between dietary protein availability and fish growth3. In salmonids, PepT1 gene has been duplicated and two transporters, i.e. PepT1a and PepT1b, have been found in the intestine. The partial and complete transport cycle of the two PepT1-type transporters of Salmo salar, ssPepT1a and ssPepT1b, heterologously expressed in Xenopus laevis oocytes, were studied using Two Electrode Voltage Clamp technique. The pre-steady state currents of ssPepT1b were like that of other fish orthologs4 but differed from those of ssPepT1a. ssPepT1a showed a slower decaying currents, and the charge vs voltage (Q/V) and time constant vs voltage (τ/V) curves shifted to more positive potentials behaving as the mammalian transporter4. In both transporters, reducing external pH from 7.6 to 6.5 slowed the transients decay, shifting to more positive potential the Q/V and τ/V curves (Fig. 1). To evaluate the transport activity of ssPepT1a and ssPepT1b, the transport-associated currents were recorded in presence of 1mM of lysine(Lys)-containing peptides (KcPeps) as Lys is a limiting amino acid for animal growth3. KcPeps elicited transport-associated currents of different amplitudes, for e.g. ssPepT1b generated large currents when exposed to peptides carrying Lys in the N-terminus (KG, KM), while ssPepT1a produced small currents independently of Lys position (Fig. 2). The current vs voltage (I/V), in the presence of KcPeps, showed small and similar currents at two different pH (6.5, 7.6) in ssPepT1a. Conversely, in ssPepT1b the I/V curves differed at the most negative potentials with larger currents ... Conference Object Salmo salar Università del Salento: CINECA IRIS |
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Università del Salento: CINECA IRIS |
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English |
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The H+-coupled peptide transporter 1 (PepT1) belongs to SoLute Carrier family 15 (SLC15A1) and is responsible for the absorption of di/tripeptides in enterocytes. Beside its nutritional role, it has been hypothesized that PepT1 functions as a transceptor, i.e. a peptide sensor/transporter involved in gut hormone release from entero-endocrine cell(s)1, 2. Studying the role of PepT1 in peptide absorption in the gut is relevant for the direct relation between dietary protein availability and fish growth3. In salmonids, PepT1 gene has been duplicated and two transporters, i.e. PepT1a and PepT1b, have been found in the intestine. The partial and complete transport cycle of the two PepT1-type transporters of Salmo salar, ssPepT1a and ssPepT1b, heterologously expressed in Xenopus laevis oocytes, were studied using Two Electrode Voltage Clamp technique. The pre-steady state currents of ssPepT1b were like that of other fish orthologs4 but differed from those of ssPepT1a. ssPepT1a showed a slower decaying currents, and the charge vs voltage (Q/V) and time constant vs voltage (τ/V) curves shifted to more positive potentials behaving as the mammalian transporter4. In both transporters, reducing external pH from 7.6 to 6.5 slowed the transients decay, shifting to more positive potential the Q/V and τ/V curves (Fig. 1). To evaluate the transport activity of ssPepT1a and ssPepT1b, the transport-associated currents were recorded in presence of 1mM of lysine(Lys)-containing peptides (KcPeps) as Lys is a limiting amino acid for animal growth3. KcPeps elicited transport-associated currents of different amplitudes, for e.g. ssPepT1b generated large currents when exposed to peptides carrying Lys in the N-terminus (KG, KM), while ssPepT1a produced small currents independently of Lys position (Fig. 2). The current vs voltage (I/V), in the presence of KcPeps, showed small and similar currents at two different pH (6.5, 7.6) in ssPepT1a. Conversely, in ssPepT1b the I/V curves differed at the most negative potentials with larger currents ... |
author2 |
Vacca, F. Gomes, A. Cinquetti, R. Murashita, K. Imperiali, F. Barca, A. Verri, T. Rønnestad, I. Bossi, E. |
format |
Conference Object |
author |
F. Vacca A. Gomes R. Cinquetti K. Murashita F. Imperiali A. Barca T. Verri I. Rønnestad E. Bossi |
spellingShingle |
F. Vacca A. Gomes R. Cinquetti K. Murashita F. Imperiali A. Barca T. Verri I. Rønnestad E. Bossi Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle |
author_facet |
F. Vacca A. Gomes R. Cinquetti K. Murashita F. Imperiali A. Barca T. Verri I. Rønnestad E. Bossi |
author_sort |
F. Vacca |
title |
Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle |
title_short |
Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle |
title_full |
Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle |
title_fullStr |
Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle |
title_full_unstemmed |
Salmo salar oligopeptide transporters PepT1a and PepT1b: a comparative electrophysiological characterization of partial and complete transport cycle |
title_sort |
salmo salar oligopeptide transporters pept1a and pept1b: a comparative electrophysiological characterization of partial and complete transport cycle |
publisher |
The Physiological Society |
publishDate |
2018 |
url |
http://hdl.handle.net/11587/443453 |
genre |
Salmo salar |
genre_facet |
Salmo salar |
op_relation |
ispartofbook:Europhysiology 2018 Europhysiology 2018 volume:41 http://hdl.handle.net/11587/443453 |
_version_ |
1790607407932506112 |