Arabidopsis; SR45; iron; metal homeostasis; serine/arginine-rich 45; splicing; zinc; Arabidopsis mutant; Biological process; Metal distributions; Plant Science
Abstract :
[en] The plant serine/arginine-rich (SR) splicing factor SR45 plays important roles in several biological processes, such as splicing, DNA methylation, innate immunity, glucose regulation, and abscisic acid signaling. A homozygous Arabidopsis sr45-1 null mutant is viable, but exhibits diverse phenotypic alterations, including delayed root development, late flowering, shorter siliques with fewer seeds, narrower leaves and petals, and unusual numbers of floral organs. Here, we report that the sr45-1 mutant presents an unexpected constitutive iron deficiency phenotype characterized by altered metal distribution in the plant. RNA-Sequencing highlighted severe perturbations in metal homeostasis, the phenylpropanoid pathway, oxidative stress responses, and reproductive development. Ionomic quantification and histochemical staining revealed strong iron accumulation in the sr45-1 root tissues accompanied by iron starvation in aerial parts. Mis-splicing of several key iron homeostasis genes, including BTS, bHLH104, PYE, FRD3, and ZIF1, was observed in sr45-1 roots. We showed that some sr45-1 developmental abnormalities can be complemented by exogenous iron supply. Our findings provide new insight into the molecular mechanisms governing the phenotypes of the sr45-1 mutant.
Disciplines :
Biochemistry, biophysics & molecular biology
Author, co-author :
Fanara, Steven ; Université de Liège - ULiège > Integrative Biological Sciences (InBioS)
Schloesser, Marie ; Université de Liège - ULiège > Département des sciences de la vie
Hanikenne, Marc ✱; Université de Liège - ULiège > Département des sciences de la vie > Biologie végétale translationnelle
Motte, Patrick ✱; Université de Liège - ULiège > Integrative Biological Sciences (InBioS)
✱ These authors have contributed equally to this work.
Language :
English
Title :
Altered metal distribution in the sr45-1 Arabidopsis mutant causes developmental defects.
F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]
Funding text :
Funding was provided by the “Fonds de la Recherche Scientifique‐FNRS” (FRFC‐1.E049.15, PDR‐T.0206.13, CDR‐J.0009.17, PDR‐T0120.18, CDR‐J.0082.21). M.H. was Senior Research Associate of the F.R.S.‐FNRS. S.F. was a doctoral fellow (F.R.I.A.).
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