Distribution of auxin and PIN proteins during somatic embryogenesis of Brachypodium distachyon

master's thesis

• Title (croatian): Lokalizacija auksina i proteina PIN tijekom somatske embriogeneze vrste Brachypodium distachyon
• Author: Luka Lelas
• Mentor: Oumaya Bouchabké-Coussa (mentor)
• Mentor: Dunja Leljak-Levanić (komentor)
• Committee member: Dunja Leljak-Levanić (predsjednik povjerenstva)
• Committee member: Željka Vidaković-Cifrek (član povjerenstva)
• Committee member: Petra Peharec Štefanić (član povjerenstva)
• Committee member: Višnja Besendorfer (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2022-12-19, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Brachypodium distachyon is a model species used for research of Poaceae. The phylogenetic
link this species shares with monocots of agronomic importance makes it the ideal model for
studying developmental mechanism with economic applications, like somatic embryogenesis
(SE). As auxin plays a critical role in SE, tracking its presence during SE enables description
of the process as a whole. For this purpose, fluorescently-tagged PIN-FORMED (PIN) auxin
transporters and presence of auxin was examined using confocal microscopy. Findings
confirmed PIN1a to be a major marker of SE as it is expressed in all stages of SE and revealed
the complementary but mutually exclusive distribution patterns of SoPIN1 and PIN1b.
Moreover, examinations of markers of auxin presence revealed how SoPIN1 and PIN1b affect
its flow and thus influence SE. Additionally, with the goal of furthering understanding of the
effect these select PIN auxin transporters have on SE, response of loss-of-function mutants
pin1a, pin1b and their cross pin1a × pin1b to in vitro SE induction was compared using
PAS/NBB staining. Results have shown no identifiable histological differences in comparison
to wild-type explants, hinting at functional redundancy of the remaining PIN transporters
allowing SE to occur.

Abstract (croatian)

Brachypodium distachyon je vrsta koja se koristi pri proučavanju porodice Poaceae. Njena
filogenetska povezanost s jednosupnicama od agronomske važnosti čini je idealnom za
proučavanje razvojnih mehanizama s ekonomskim primjenama, poput somatske embriogeneze
(SE). Kako auksin ima ključnu ulogu u SE, praćenje njegove prisutnosti tijekom SE omogućava
opisivanje tog procesa u cjelini. U tu svrhu, odabrani su fluorescentno označeni transporteri
auksina PIN-FORMED (PIN) za prisutnost auksina te proučeni pomoću konfokalnog
mikroskopa ili konfokalne mikroskopije. Rezultati su pokazali da je PIN1a važan marker SE
budući da je eksprimiran tijekom svih stadija SE te da su obrasci distribucije SoPIN1 i PIN1b
komplementarni i međusobno isključivi. Štoviše, proučavanje markera prisutnosti auksina
pokazalo je na koji način SoPIN1 i PIN1b utječu na njegov tok i time oblikuju SE. Uz navedeno
je proučen učinak odabranih PIN auksinskih transportera na proces SE, uspoređujući odgovor
loss-of-function mutanta pin1a, pin1b te njihovog križanca pin1a × pin1b na indukciju SE in
vitro koristeći se bojanjem PAS/NBB. Histološke razlike mutanata i eksplantanata divljeg tipa
nisu utvrđene, što ukazuje kako funkcionalna redundantnost preostalih proteina PIN
omogućava odvijanje SE.

• Keywords: Brachypodium; in vitro culture; somatic embryogenesis; confocal microscopy
• Keywords (english): Brachypodium; in vitro uzgoj; somatska embriogeneza; konfokalna mikroskopija
• Language: croatian
• URN:NBN: urn:nbn:hr:217:010033
• Study programme: Title: Molecular Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra molekularne biologije (magistar/magistra molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2024-12-19
• Created on: 2022-12-22 08:38:59