Gene Details:

• MSU gene ID: None
• RAPdb gene ID: None
• Gene Symbol: Sub1A
• Genome: MSU7 ,  IRGSP-1.0
• Species: Oryza sativa

Functional Descriptions:

• Sub1A is an ethylene-response-factor-like gene that confers submergence tolerance to rice.
• Acclimation responses to submergence are coordinated by the submergence-inducible Sub1A, which encodes an ethylene-responsive factor-type transcription factor (ERF).
• Overexpression of Sub1A augmented ABA responsiveness, thereby activating stress-inducible gene expression.
• The submergence tolerance regulator Sub1A mediates stress-responsive expression of AP2/ERF transcription factors.
• Sub1A, an ERF transcription factor found in limited rice accessions, dampens ethylene production and gibberellic acid responsiveness during submergence, economizing carbohydrate reserves and significantly prolonging endurance.
• Rice varieties possessing the submergence 1A (Sub1A) gene display a distinct flooding-tolerant phenotype, associated with lower carbohydrate consumption and restriction of the fast-elongation phenotype typical of flooding-intolerant rice varieties.
• Comparative analysis of genotypes with and without Sub1A revealed that Sub1A enhanced recovery from drought at the vegetative stage through reduction of leaf water loss and lipid peroxidation and increased expression of genes associated with acclimation to dehydration.
• Jasmonate and salicylic acid are positive regulators of leaf senescence, but ectopic overexpression of Sub1A dampened responsiveness to both hormones in the context of senescence.
• Overall, Sub1A genotypes displayed altered responses to prolonged darkness by limiting ethylene production and responsiveness to jasmonate and salicylic acid, thereby dampening the breakdown of chlorophyll, carbohydrates, and the accumulation of senescence-associated messenger RNAs.
• Consistently, Sub1A increased the abundance of transcripts encoding ROS scavenging enzymes, resulting in enhanced tolerance to oxidative stress.
• SUB1 encodes two or three transcription factors of the group VII ethylene response factor family: Sub1A, SUB1B and SUB1C.
• The presence of Sub1A-1 and its strong submergence-triggered ethylene-mediated induction confers submergence tolerance through a quiescence survival strategy that inhibits gibberellin (GA)-induced carbohydrate consumption and elongation growth.
• The submergence-stimulated decrease in ABA content was Sub1A-independent, whereas GA-mediated underwater elongation was significantly restricted by Sub1A.
• Specific expression in the growing part of rice leaves is well in agreement with the role of Sub1A in suppressing leaf elongation under submergence.
• Molecular marker survey and expression analyses of the rice submergence-tolerance gene Sub1A.
• Sub1A is limited to tolerant genotypes and sufficient to confer submergence tolerance to intolerant accessions.
• Here we evaluated the role of Sub1A in the integration of ethylene, abscisic acid (ABA), and gibberellin (GA) signaling during submergence.
• In the Sub1A overexpression line, SLR1 protein levels declined under prolonged submergence but were accompanied by an increase in accumulation of SLRL1, which lacks the DELLA domain.
• Together, these results demonstrate that Sub1A limits ethylene-promoted GA responsiveness during submergence by augmenting accumulation of the GA signaling repressors SLR1 and SLRL1.
• Submergence tolerance conferred by Sub1A is mediated by SLR1 and SLRL1 restriction of gibberellin responses in rice.
• Expression of rice Sub1A and SUB1C transcription factors in Arabidopsis uncovers flowering inhibition as a submergence tolerance mechanism.
• A delay of leaf senescence conferred by Sub1A can contribute to the enhancement of tolerance to submergence, drought, and oxidative stress.
• Initial analyses of leaf samples failed to reveal a clear association of Sub1A transcript abundance and tolerance.
• Sub1A also restrained accumulation of reactive oxygen species (ROS) in aerial tissue during drought and desubmergence.
• Therefore, in addition to providing robust submergence tolerance, Sub1A improves survival of rapid dehydration following desubmergence and water deficit during drought.
• The submergence tolerance regulator Sub1A mediates crosstalk between submergence and drought tolerance in rice.
• As in rice transgenic plants that ectopically express Sub1A-1, Arabidopsis transgenic plants that constitutively express Sub1A displayed GA insensitivity and abscisic acid hypersensitivity.
• The objectives of this study were to (a) develop mega varieties with Sub1 introgression that are submergence tolerant, (b) assess the performance of Sub1 in different genetic backgrounds, (c) determine the roles of the Sub1A and Sub1C genes in conferring tolerance, and (d) assess the level of tolerance in F(1) hybrids heterozygous for the Sub1A-1-tolerant allele.
• In adult plants Sub1A and CIPK15 may perhaps play an antagonistic role in terms of carbohydrate consumption, with Sub1A acting as a starch degradation repressor and CIPK15 as an activator.
• Here, we evaluated the influence of the submergence tolerance regulator, SUBMERGENCE1A (Sub1A), in the acclimation responses during leaf senescence caused by prolonged darkness in rice (Oryza sativa).
• Physiological analysis revealed that Sub1A postpones dark-induced senescence through the maintenance of chlorophyll and carbohydrate reserves in photosynthetic tissue.
• Sub1A also restricted the transcript accumulation of representative senescence-associated genes.
• We found that ethylene accelerated senescence stimulated by darkness and jasmonate, although Sub1A significantly restrained dark-induced ethylene accumulation.
• The submergence tolerance gene Sub1A delays leaf senescence under prolonged darkness through hormonal regulation in rice.
• Genotypes carrying the Sub1A-1 allele are tolerant of prolonged submergence.
• To elucidate the mechanism of Sub1A-1-mediated tolerance, we performed transcriptome analyses comparing the temporal submergence response of Sub1A-1-containing tolerant M202(Sub1) with the intolerant isoline M202 lacking this gene.
• Of particular interest were a set of APETALA2 (AP2)/ERF family transcriptional regulators that are associated with the Sub1A-1-mediated response upon submergence.
• These results confirm that the presence of Sub1A-1 impacts multiple pathways of response to submergence.
• Observation of a delayed flowering phenotype in lines over-expressing Sub1A led to the finding that inhibition of floral initiation is a component of the quiescence survival strategy in rice.
• In the presence of Sub1A, the increase in these GA signaling repressors and decrease in GA responsiveness were stimulated by ethylene, which promotes Sub1A expression.
• Genotypes with conditional and ectopic overexpression of Sub1A significantly delayed loss of leaf color and enhanced recovery from dark stress.
• Overexpression of Sub1A-1 in a submergence-intolerant O.
• japonica conferred enhanced tolerance to the plants, downregulation of Sub1C and upregulation of Alcohol dehydrogenase 1 (Adh1), indicating that Sub1A-1 is a primary determinant of submergence tolerance.
• Desubmergence caused the upregulation of gene transcripts associated with acclimation to dehydration, with higher induction in Sub1A genotypes.
• Notably Sub1A increased the accumulation of the GA signaling repressors Slender Rice-1 (SLR1) and SLR1 Like-1 (SLRL1) and concomitantly diminished GA-inducible gene expression under submerged conditions.
• Our findings illuminate the significant role of Sub1A in active physiological recovery upon desubmergence, a component of enhanced tolerance to submergence.
• The ethylene response factor-like protein Sub1A orchestrates a plethora of responses during submergence stress tolerance in rice.
• Rice Sub1A constrains remodeling of the transcriptome and metabolome during submergence to facilitate post-submergence recovery.
• Here, transcriptomic and metabolomic analyses were conducted to identify mechanisms by which Sub1A improves physiological function over the 24 hours following a sub-lethal submergence event.
• Evaluation of near-isogenic genotypes after submergence and over a day of re-aeration demonstrated that Sub1A transiently constrains the remodeling of cellular activities associated with growth.
• The involvement of low energy sensing during submergence and recovery was supported by dynamics in trehalose-6-phosphate (T6P) and mRNAs encoding key enzymes and signaling proteins, which were modulated by Sub1A.
• Sub1A promoted recovery of metabolic homeostasis but had limited influence on mRNAs associated with growth processes and photosynthesis.
• In both leaf types, pathways involved in carbohydrate and nitrogen metabolism were suppressed by Sub1A, with more severe restriction in growing leaves that have a greater energy demand if Sub1A is absent.
• The submergence tolerance regulator Sub1A differentially coordinates molecular adaptation to submergence in mature and growing leaves of rice (Oryza sativa L.).
• However, the molecular and physiological functions of Sub1A have been characterized using entire shoot tissues, most of which are mature leaves that do not elongate under submergence.
• To this end, we compared the transcriptomic and hormonal responses to submergence between mature and growing leaves using rice genotypes with and without Sub1A.
• In mature leaves, submergence-induced auxin accumulation was suppressed by Sub1A.

Function-related keywords:

• ethylene ,  transcription-factor ,  ABA ,  submergence ,  vegetative ,  salicylic-acid ,  oxidative ,  leaf ,  drought ,  growth ,  gibberellin ,  ga ,  starch ,  drought-tolerance ,  senescence ,  floral ,  flower ,  jasmonate ,  tolerance ,  stress ,  ethylene-response ,  stress-tolerance ,  photosynthesis ,  homeostasis ,  nitrogen ,  shoot ,  auxin ,  mature-leaves ,  submergence-tolerance

Literature:

• The submergence tolerance regulator Sub1A mediates stress-responsive expression of AP2/ERF transcription factors .  DOI:  10.1104/pp.109.152157 ;  PMID:  20107022
• The submergence tolerance gene SUB1A delays leaf senescence under prolonged darkness through hormonal regulation in rice .  DOI:  10.1104/pp.112.207738 ;  PMID:  23073696
• Development of submergence-tolerant rice cultivars: the Sub1 locus and beyond .  DOI:  10.1093/aob/mcn206 ;  PMID:  18974101
• Submergence tolerance conferred by Sub1A is mediated by SLR1 and SLRL1 restriction of gibberellin responses in rice .  DOI:  10.1073/pnas.0807821105 ;  PMID:  18936491
• The submergence tolerance regulator SUB1A mediates crosstalk between submergence and drought tolerance in rice .  DOI:  10.1105/tpc.110.080325 ;  PMID:  21239643
• Expression of rice SUB1A and SUB1C transcription factors in Arabidopsis uncovers flowering inhibition as a submergence tolerance mechanism .  DOI:  10.1111/j.1365-313X.2011.04605.x ;  PMID:  21481028
• Regulatory interplay of the Sub1A and CIPK15 pathways in the regulation of α-amylase production in flooded rice plants .  DOI:  10.1111/j.1438-8677.2010.00415.x ;  PMID:  21668602
• Sub1A is an ethylene-response-factor-like gene that confers submergence tolerance to rice .  DOI:  10.1038/nature04920 ;  PMID:  16900200
• Molecular marker survey and expression analyses of the rice submergence-tolerance gene SUB1A .  DOI:  10.1007/s00122-010-1400-z ;  PMID:  20652530
• The key regulator of submergence tolerance, SUB1A, promotes photosynthetic and metabolic recovery from submergence damage in rice leaves .  DOI:  10.1111/pce.12661 ;  PMID:  26477688
• A Positive Feedback Loop Governed by SUB1A1 Interaction with MITOGEN-ACTIVATED PROTEIN KINASE3 Imparts Submergence Tolerance in Rice .  DOI:  10.1105/tpc.15.01001 ;  PMID:  27081183
• Rice SUB1A constrains remodelling of the transcriptome and metabolome during submergence to facilitate post-submergence recovery .  DOI:  10.1111/pce.13094 ;  PMID:  29094353
• Allelic variants of OsSUB1A cause differential expression of transcription factor genes in response to submergence in rice .  DOI:  10.1186/s12284-017-0192-z ;  PMID:  29313187
• Regulatory cascade involving transcriptional and N-end rule pathways in rice under submergence .  DOI:  10.1073/pnas.1818507116 ;  PMID:  30723146
• Introgression of Sub1 (SUB1) QTL in mega rice cultivars increases ethylene production to the detriment of grain- filling under stagnant flooding .  DOI:  10.1038/s41598-019-54908-2 ;  PMID:  31811177
• The submergence tolerance regulator SUB1A differentially coordinates molecular adaptation to submergence in mature and growing leaves of rice (Oryza sativa L.) .  DOI:  10.1111/tpj.15654 ;  PMID:  34978355

Related News:

Gene Resources:

• NCBI ID:
• UniProt accessions:

Sequences: