Conclusioni e prospettive future

I risultati ottenuti ci hanno permesso di osservare una risposta organo-specifica e gene-specifica causata dal trattamento a concentrazione sub-letale di zinco. Infatti, tutti i trasportatori ZIP sono espressi a livello della radice tra cui Zip4 e Zip9 che presentano un forte cambio d’espressione rispetto al controllo. Interessante è risultato il comportamento di Zip6 che presenta una sotto espressione statisticamente significativa in tutti gli organi delle piante in entrambi i sistemi utilizzati.

I risultati ottenuti ci hanno permesso di effettuare ipotesi sul ruolo dei geni Zip che governano insieme alle altre famiglie di trasportatori l’omeostasi dei metalli nella pianta. Non dobbiamo dimenticare che i risultati da noi ottenuti sono, quindi, influenzati indirettamente dai livelli d’espressione di tutti i trasportatori presenti nella pianta. Questo è stato uno studio preliminare che suggerisce l’allestimento di tutta una serie di prove atte alla caratterizzazione dei vari trasportatori nel pioppo. Infatti, i gruppi di geni Zip che presentano un tendente aumento o abbassamento dei livelli d’espressione non significativo statisticamente a seguito del trattamento, potrebbero essere oggetto di futuri studi in cui affinare il rilevamento di questi misurando l’espressione dei singoli geni facenti parte del gruppo. Ulteriori studi potrebbero essere condotti sugli Zip e su altre famiglie di trasportatori sia in carenza che in eccesso di zinco. Inoltre, l’allestimento di prove di stress da eccesso o da carenza di altri metalli permetterebbe la conferma di eventuali competizioni nell’assorbimento e lo studio della variazione alla risposta dei trasportatori ai vari metalli.

Le linee di piante transgeniche con UPr51 potranno essere utilizzate per effettuare prove di carenza e di eccesso di zinco in modo tale da rilevare l’effetto indotto sulla pianta dalla sovra espressione di questo trasportatore ZIP. Inoltre, una migliore comprensione del funzionamento di questi trasportatori all’interno della pianta sarebbe possibile tramite la creazione di altre piante transgeniche silenziando o sovra esprimendo i geni Zip studiati e allestendo prove non solo in presenza di un eccesso di zinco ma anche in carenza.

109

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120

Ringraziamenti

Ringrazio il prof.re Andrea Andreucci e Lara Lombardi dell’Università di Pisa per la pazienza e la collaborazione.

Ringrazio tutto il personale dei BioLabs dell’istituto di scienza della vita della Scuola Superiore Sant’Anna per la disponibilità e la collaborazione alla tesi, in particolare volevo ringraziare: Alessandra Francini, Andrea Ariani, Chiara Romè, Cristina Ghelardi, Roberta Tosetti, Gaia Monteforti e Stefania Romeo.

Ringrazio tutti i miei amici vecchi e nuovi che mi sono stati vicini in questi duri 2 anni, in

particolare: Raffaele Luongo e Gianmarco Meo, Giovanni Giangreco, Michele Tarabella, Lorenzo Bascetta, Giacomo Siano e Cristina Romani.

Ringrazio la mia ragazza Giulia per essermi stata accanto anche nei momenti più bui e sconfortanti di questa laurea magistrale con pazienza e dedizione.

Ringrazio mio fratello Vincenzo che mi ha sempre dato una mano ed ha creduto in me nel bene e nel male.

Ringrazio i miei cugini Lorenzo, Enrico e Luisa che con la loro permanenza a Pisa hanno permesso di creare un pezzo di famiglia sicula nella verde Toscana.

Ringrazio i miei genitori che mi hanno sempre appoggiato anche nelle scelta di questo campo con un incerto futuro lavorativo. Spero di non aver mai deluso le loro aspettative e che mai le deluderò. Ringrazio tutta la mia famiglia e la mia Terra d’origine che per quanto problematica mi ha generato e suscita sempre in me un’attrazione silenziosa.