Exosomes (EXs) formed within the endosomal network and released upon fusion of multi-vesicular bodies with the plasma membrane into the surrounding environment. EXs play an important role in intercellular communication by transporting proteins and RNA. Plant EXs seem to mediate the transport of proteins to the extracellular compartment (apoplast) and could account for the so-called unconventional secretion pathway, where proteins lacking a signal peptide secreted in extracellular fluids. γ-Conglutin (Cγ) from the leguminous plant Lupinus albus has been considered for a long time a storage protein, but recent studies definitely ruled out this function evidencing a multifaceted involvement in plant defence mechanisms triggered by pathogens attacks. Beside its physiological role, Cγ set off a remarkable pharmacological interest, too. It was proved to significantly decrease glycaemia in humans and animals when orally administered. The applicative fall backs of these findings are relevant, being γ-conglutin a natural dietary component that could complement pharmacotherapy in the management of diabetes. However, this protein is known to be one of the major allergens of lupin seeds. In developing seeds, Cγ is deposited inside protein bodies through the secretory pathway. During germination, Cγ is localized in the apoplasts of germinating seeds while the storage vacuoles appeared void of the protein. How γ-conglutin reaches the extracellular regions is still matter of debate. The present work aimed to investigate if Cγ is secreted outside the cotyledonary cells during the very first moments of seed germination is conveyed by EXs. The results obtained by a combination of vacuum infiltration, 1D- and 2D-gel electrophoresis, ultracentrifugation fractionation and immunoblotting techniques, indicate that after 16 hours from the germination onset Cγ is the most represented protein in apoplast and that it is confined in vesicular material. The hypothesis that the seed-stored protein is released outside the cells through an unconventional secretory vesicles-based pathway, as it occurs for sunflower seed agglutinin 1 and other seed proteins, is suggestive and needs further focused investigations.

Exosomes are released by germinating lupin seeds and mainly contain a major food allergene / I. Riccardi, P. Corsetto, J. Capraro, A. Scarafoni. ((Intervento presentato al 5. convegno Incontro dei Giovani Biochimici dell'Area Lombarda tenutosi a Gargnano nel 2019.

Exosomes are released by germinating lupin seeds and mainly contain a major food allergene

P. Corsetto
Secondo
;
J. Capraro;A. Scarafoni
Ultimo
2019

Abstract

Exosomes (EXs) formed within the endosomal network and released upon fusion of multi-vesicular bodies with the plasma membrane into the surrounding environment. EXs play an important role in intercellular communication by transporting proteins and RNA. Plant EXs seem to mediate the transport of proteins to the extracellular compartment (apoplast) and could account for the so-called unconventional secretion pathway, where proteins lacking a signal peptide secreted in extracellular fluids. γ-Conglutin (Cγ) from the leguminous plant Lupinus albus has been considered for a long time a storage protein, but recent studies definitely ruled out this function evidencing a multifaceted involvement in plant defence mechanisms triggered by pathogens attacks. Beside its physiological role, Cγ set off a remarkable pharmacological interest, too. It was proved to significantly decrease glycaemia in humans and animals when orally administered. The applicative fall backs of these findings are relevant, being γ-conglutin a natural dietary component that could complement pharmacotherapy in the management of diabetes. However, this protein is known to be one of the major allergens of lupin seeds. In developing seeds, Cγ is deposited inside protein bodies through the secretory pathway. During germination, Cγ is localized in the apoplasts of germinating seeds while the storage vacuoles appeared void of the protein. How γ-conglutin reaches the extracellular regions is still matter of debate. The present work aimed to investigate if Cγ is secreted outside the cotyledonary cells during the very first moments of seed germination is conveyed by EXs. The results obtained by a combination of vacuum infiltration, 1D- and 2D-gel electrophoresis, ultracentrifugation fractionation and immunoblotting techniques, indicate that after 16 hours from the germination onset Cγ is the most represented protein in apoplast and that it is confined in vesicular material. The hypothesis that the seed-stored protein is released outside the cells through an unconventional secretory vesicles-based pathway, as it occurs for sunflower seed agglutinin 1 and other seed proteins, is suggestive and needs further focused investigations.
2019
Settore BIO/10 - Biochimica
Exosomes are released by germinating lupin seeds and mainly contain a major food allergene / I. Riccardi, P. Corsetto, J. Capraro, A. Scarafoni. ((Intervento presentato al 5. convegno Incontro dei Giovani Biochimici dell'Area Lombarda tenutosi a Gargnano nel 2019.
Conference Object
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

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/2434/662103
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact