Publikation:

The Eyes of Diatoms: Molecular Mechanisms of Aureochromes in the Diatom Phaeodactylum tricornutum

Lade...
Vorschaubild

Dateien

Im-2-bhy5zad6zf846.pdf
Im-2-bhy5zad6zf846.pdfGröße: 19.37 MBDownloads: 39

Datum

2023

Autor:innen

Herausgeber:innen

Kontakt

ISSN der Zeitschrift

Electronic ISSN

ISBN

Bibliografische Daten

Verlag

Schriftenreihe

Auflagebezeichnung

DOI (zitierfähiger Link)
ArXiv-ID

Internationale Patentnummer

Link zur Lizenz

Angaben zur Forschungsförderung

Projekt

Open Access-Veröffentlichung
Open Access Green
Core Facility der Universität Konstanz

Gesperrt bis

Titel in einer weiteren Sprache

Publikationstyp
Dissertation
Publikationsstatus
Published

Erschienen in

Zusammenfassung

Diatoms are unicellular microalgae thriving in various aquatic habitats, utilizing photoreceptors to precisely detect light quantity and quality (color) and adjusting their physiology accordingly. Aureochromes (AUREOs) are blue light receptors that also function as bZIP (basic leucine zipper) transcription factors. The model diatom Phaeodactylum tricornutum encodes four Aureo genes: PtAureo1a, 1b, 1c, and 2. PtAUREO1a has been shown to significantly impact overall gene regulation and light acclimation. However, the molecular mechanisms of PtAUREO1a's gene regulation remain unclear and only little is known about other PtAUREO paralogs. Here, we study the biological roles of individual PtAUREOs and unravel their functional mechanisms. We demonstrate the distinct light absorptions of individual PtAUREOs and investigate the disparate protein stabilities of PtAUREO1a and PtAUREO1b upon a shift from red light to blue light: PtAUREO1a is rapidly degraded by the proteasome, while PtAUREO1b shows no significant changes. These findings suggest distinctive functions of individual PtAUREOs with different light sensitivities and represent the first experimental demonstration of a functional proteasome-ubiquitin system in P. tricornutum. Using pull-down assays, we verify that all combinations of PtAUREO dimers can be formed, suggesting the cooperative functions of PtAUREOs and the potential expansion of their target genes. Using a modified yeast one-hybrid assay, we identify PtAUREO1a’s target genes, including transcription factors like PtbZIP10, PtAureo1a, PtAureo1c, PtbHLH2_PAS, and PtHSF3.2b. These genes may trigger further signal cascades, thus enabling PtAUREO1a to indirectly regulate a wide range of genes. We found that PtAUREO1a and PtAUREO1b can initiate gene transcription without blue light illumination and that PtAUREO1a may not require either blue light or an Aureo box, a known binding motif of AUREOs (5’-TGACGT-3’), for gene regulation. By examining mutant lines of P. tricornutum expressing a mutated PtAUREO1a with a significant loss of light absorption (PtBlindA1a), we find novel evidence that PtAUREO1a impacts PtLhcf15 gene expression, which is essential for red light acclimation. Also, through characterizing TALEN-mediated PtAureo1c knock-out mutants, we reveal that PtAUREO1c is involved in red light acclimation, photoprotection, and cell cycle regulation. In conclusion, PtAUREOs are transcription factors that finely tune gene expression and cell physiology in response to light signals, which may contribute to diatoms' high acclimation capacity in various environments.

Zusammenfassung in einer weiteren Sprache

Fachgebiet (DDC)
570 Biowissenschaften, Biologie

Schlagwörter

Konferenz

Rezension
undefined / . - undefined, undefined

Forschungsvorhaben

Organisationseinheiten

Zeitschriftenheft

Zugehörige Datensätze in KOPS

Zitieren

ISO 690IM, Soo Hyun, 2023. The Eyes of Diatoms: Molecular Mechanisms of Aureochromes in the Diatom Phaeodactylum tricornutum [Dissertation]. Konstanz: Universität Konstanz
BibTex
@phdthesis{Im2023Diato-70441,
  year={2023},
  title={The Eyes of Diatoms: Molecular Mechanisms of Aureochromes in the Diatom Phaeodactylum tricornutum},
  author={Im, Soo Hyun},
  address={Konstanz},
  school={Universität Konstanz}
}
RDF
<rdf:RDF
    xmlns:dcterms="http://purl.org/dc/terms/"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:bibo="http://purl.org/ontology/bibo/"
    xmlns:dspace="http://digital-repositories.org/ontologies/dspace/0.1.0#"
    xmlns:foaf="http://xmlns.com/foaf/0.1/"
    xmlns:void="http://rdfs.org/ns/void#"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema#" > 
  <rdf:Description rdf:about="https://kops.uni-konstanz.de/server/rdf/resource/123456789/70441">
    <dspace:isPartOfCollection rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/28"/>
    <dcterms:issued>2023</dcterms:issued>
    <dcterms:available rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2024-07-23T10:03:15Z</dcterms:available>
    <dcterms:rights rdf:resource="http://creativecommons.org/licenses/by/4.0/"/>
    <dcterms:abstract>Diatoms are unicellular microalgae thriving in various aquatic habitats, utilizing photoreceptors to precisely detect light quantity and quality (color) and adjusting their physiology accordingly. Aureochromes (AUREOs) are blue light receptors that also function as bZIP (basic leucine zipper) transcription factors. The model diatom Phaeodactylum tricornutum encodes four Aureo genes: PtAureo1a, 1b, 1c, and 2. PtAUREO1a has been shown to significantly impact overall gene regulation and light acclimation. However, the molecular mechanisms of PtAUREO1a's gene regulation remain unclear and only little is known about other PtAUREO paralogs. 
Here, we study the biological roles of individual PtAUREOs and unravel their functional mechanisms. We demonstrate the distinct light absorptions of individual PtAUREOs and investigate the disparate protein stabilities of PtAUREO1a and PtAUREO1b upon a shift from red light to blue light: PtAUREO1a is rapidly degraded by the proteasome, while PtAUREO1b shows no significant changes. These findings suggest distinctive functions of individual PtAUREOs with different light sensitivities and represent the first experimental demonstration of a functional proteasome-ubiquitin system in P. tricornutum.
Using pull-down assays, we verify that all combinations of PtAUREO dimers can be formed, suggesting the cooperative functions of PtAUREOs and the potential expansion of their target genes. Using a modified yeast one-hybrid assay, we identify PtAUREO1a’s target genes, including transcription factors like PtbZIP10, PtAureo1a, PtAureo1c, PtbHLH2_PAS, and PtHSF3.2b. These genes may trigger further signal cascades, thus enabling PtAUREO1a to indirectly regulate a wide range of genes. We found that PtAUREO1a and PtAUREO1b can initiate gene transcription without blue light illumination and that PtAUREO1a may not require either blue light or an Aureo box, a known binding motif of AUREOs (5’-TGACGT-3’), for gene regulation. By examining mutant lines of P. tricornutum expressing a mutated PtAUREO1a with a significant loss of light absorption (PtBlindA1a), we find novel evidence that PtAUREO1a impacts PtLhcf15 gene expression, which is essential for red light acclimation. Also, through characterizing TALEN-mediated PtAureo1c knock-out mutants, we reveal that PtAUREO1c is involved in red light acclimation, photoprotection, and cell cycle regulation.
In conclusion, PtAUREOs are transcription factors that finely tune gene expression and cell physiology in response to light signals, which may contribute to diatoms' high acclimation capacity in various environments.</dcterms:abstract>
    <dspace:hasBitstream rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/70441/4/Im-2-bhy5zad6zf846.pdf"/>
    <dc:date rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2024-07-23T10:03:15Z</dc:date>
    <dc:creator>Im, Soo Hyun</dc:creator>
    <bibo:uri rdf:resource="https://kops.uni-konstanz.de/handle/123456789/70441"/>
    <void:sparqlEndpoint rdf:resource="http://localhost/fuseki/dspace/sparql"/>
    <dcterms:isPartOf rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/28"/>
    <dcterms:hasPart rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/70441/4/Im-2-bhy5zad6zf846.pdf"/>
    <dc:rights>Attribution 4.0 International</dc:rights>
    <dc:language>eng</dc:language>
    <dc:contributor>Im, Soo Hyun</dc:contributor>
    <dcterms:title>The Eyes of Diatoms: Molecular Mechanisms of Aureochromes in the Diatom Phaeodactylum tricornutum</dcterms:title>
    <foaf:homepage rdf:resource="http://localhost:8080/"/>
  </rdf:Description>
</rdf:RDF>

Interner Vermerk

xmlui.Submission.submit.DescribeStep.inputForms.label.kops_note_fromSubmitter

Kontakt
URL der Originalveröffentl.

Prüfdatum der URL

Prüfungsdatum der Dissertation

March 8, 2024
Hochschulschriftenvermerk
Konstanz, Univ., Diss., 2024
Finanzierungsart

Kommentar zur Publikation

Allianzlizenz
Corresponding Authors der Uni Konstanz vorhanden
Internationale Co-Autor:innen
Universitätsbibliographie
Ja
Begutachtet
Diese Publikation teilen