Gene Details:

• MSU gene ID: LOC_Os03g26210
• RAPdb gene ID: Os03g0379300
• Gene Symbol: OsIRO3 OsOsbHLH063
• Genome: MSU7 ,  IRGSP-1.0
• Species: Oryza sativa

Functional Descriptions:

• RESULTS: Transcript abundance of one nuclear located basic helix-loop-helix family transcription factor, OsIRO3, is up-regulated from 25- to 90-fold under Fe deficiency in both root and shoot respectively.
• CONCLUSION: A novel Fe regulated bHLH transcription factor (OsIRO3) that plays an important role for Fe homeostasis in rice was identified.
• Furthermore, the Fe concentration in shoots of transgenic rice plants over-expressing OsIRO3 was less than that in wild-type plants.
• OsIRO3 is expressed in the roots, leaves, and base nodes, with a higher level in leaf blades at the vegetative growth stage.
• Knockout of OsIRO3 resulted in a hypersensitivity to Fe deficiency, with severe necrosis on young leaves and defective root development.
• OsIRO3 Plays an Essential Role in Iron Deficiency Responses and Regulates Iron Homeostasis in Rice.
• However, the molecular mechanisms by which OsIRO3 regulate Fe homeostasis is unclear.
• Here, we report that OsIRO3 is essential for responding to Fe deficiency and maintaining Fe homeostasis in rice.
• Thus, we conclude that OsIRO3 plays a key role in responding to Fe deficiency and regulates NA levels by directly, negatively regulating the OsNAS3 expression.
• A Model to Incorporate the bHLH Transcription Factor OsIRO3 within the Rice Iron Homeostasis Regulatory Network.
• We place our results in the context of the existing literature and generate a model describing the role of OsIRO3 in rice Fe homeostasis and reinforce the essential function of OsIRO3 in the rice Fe deficiency response.
• Further analysis revealed that OsIRO3 directly regulated the expression of IRON-RELATED BHLH TRANSCRIPTION FACTOR 2 (OsIRO2), which encodes a positive regulator of the Fe uptake system.
• Loss-of-function of OsIRO3 caused upregulation of Fe deficiency-associated genes in the root.
• OsIRO3 negatively regulates Fe homeostasis by repressing the expression of OsIRO2.
• Further investigation demonstrated that OsIRO3 interacted with POSITIVE REGULATOR OF IRON HOMEOSTASIS 1(OsPRI1) and OsPRI2, and.
• This work sheds light on the molecular mechanism by which OsIRO3 modulates Fe homeostasis in rice.
• OsIRO3 negatively regulates Fe homeostasis by repressing the expression of OsIRO2.

Function-related keywords:

• root ,  transcription-factor ,  homeostasis ,  shoot ,  leaf ,  growth ,  development ,  vegetative ,  root-development ,  iron ,  Fe ,  iron-homeostasis ,  Fe-homeostasis

Literature:

• Identification of a novel iron regulated basic helix-loop-helix protein involved in Fe homeostasis in Oryza sativa .  DOI:  10.1186/1471-2229-10-166 ;  PMID:  20699001
• OsIRO3 Plays an Essential Role in Iron Deficiency Responses and Regulates Iron Homeostasis in Rice .  DOI:  10.3390/plants9091095 ;  PMID:  32854449
• A Model to Incorporate the bHLH Transcription Factor OsIRO3 within the Rice Iron Homeostasis Regulatory Network .  DOI:  10.3390/ijms23031635 ;  PMID:  35163555
• OsIRO3 negatively regulates Fe homeostasis by repressing the expression of OsIRO2 .  DOI:  10.1111/tpj.15864 ;  PMID:  35689518

Related News:

Gene Resources:

• NCBI ID:
• UniProt accessions:

Sequences: