The DnaJ-like Zinc Finger Protein ORANGE Promotes Proline Biosynthesis in Drought-Stressed <i<Arabidopsis</i< Seedlings

Orange (OR) is a DnaJ-like zinc finger protein with both nuclear and plastidial localizations. OR, and its orthologs, are highly conserved in flowering plants, sharing a characteristic C-terminal tandem 4× repeats of the CxxCxxxG signature. It was reported to trigger chromoplast biogenesis, promote carotenoid accumulation in plastids of non-pigmented tissues, and repress chlorophyll biosynthesis and chloroplast biogenesis in the nucleus of de-etiolating cotyledons cells. Its ectopic overexpression was found to enhance plant resistance to abiotic stresses. Here, we report that the expression of OR in <i<Arabidopsis thaliana</i< was upregulated by drought treatment, and seedlings of the OR-overexpressing (OE) lines showed improved growth performance and survival rate under drought stress. Compared with the wild-type (WT) and OR-silencing (or) lines, drought-stressed OE seedlings possessed lower contents of reactive oxygen species (such as H<sub<2</sub<O<sub<2</sub< and O<sub<2</sub<<sup<−</sup<), higher activities of both superoxide dismutase and catalase, and a higher level of proline content. Our enzymatic assay revealed a relatively higher activity of Δ<sup<1</sup<-pyrroline-5-carboxylate synthase (P5CS), a rate-limiting enzyme for proline biosynthesis, in drought-stressed OE seedlings, compared with the WT and or lines. We further demonstrated that the P5CS activity could be enhanced by supplementing exogenous OR in our in vitro assays. Taken together, our results indicated a novel contribution of OR to drought tolerance, through its impact on proline biosynthesis..

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:23

Enthalten in:

International Journal of Molecular Sciences - 23(2022), 7, p 3907

Sprache:

Englisch

Beteiligte Personen:

Farman Ali [VerfasserIn]
Qi Wang [VerfasserIn]
Aliya Fazal [VerfasserIn]
Lin-Juan Wang [VerfasserIn]
Shuyan Song [VerfasserIn]
Meng-Juan Kong [VerfasserIn]
Tariq Mahmood [VerfasserIn]
Shan Lu [VerfasserIn]

Links:

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Themen:

Δ
Biology (General)
Chemistry
Drought
Enzymatic activity
ORANGE
Proline

doi:

10.3390/ijms23073907

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

DOAJ000936782