PtiCYP85A3, a BR C-6 Oxidase Gene, Plays a Critical Role in Brassinosteroid-Mediated Tension Wood Formation in Poplar

The lowest nodes of 6-week-old Aesculus turbinata seedlings were treated with uniconazole-P, an inhibitor of gibberellin (GA) biosynthesis, or a mixture of uniconazole-P and GA3 in acetone solution. To the seedling stems, an inhibitor of auxin transport (NPA) or inhibitors of auxin action (raphanusanin or MBOA) were applied in lanolin paste. The seedlings were tilted at a 45° angle and kept for 10 weeks before histological analysis. Decreases in both normal and tension wood formation followed the application of uniconazole-P. The application of GA3 together with uniconazole-P partially negated the effect of uniconazole-P alone. The application of NPA inhibited tension wood formation at, above, and below the lanolin-treated portions. The treatment of raphanusanin or MBOA also resulted in decreases in tension wood formation at the treated portions. The inhibitory effects of these chemicals applied on the upper side of tilted stems or around the entire stem were greater than on the lower side. The application of uniconazole-P in combination with raphanusanin, MBOA or NPA showed synergistic effects on the inhibition of tension wood formation. The results suggest that both auxin and GA regulate the quantitative production of tension wood fibers and are essential to tension wood formation.

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Ethylene Evolution Changes in TiltedFraxinus mandshuricaRupr. var.japonicaMaxim. Seedlings in Relation to Tension Wood Formation

Journal of Integrative Plant Biology ◽

10.1111/j.1744-7909.2009.00835.x ◽

2009 ◽

Vol 51 (7) ◽

pp. 707-713 ◽

Cited By ~ 2

Author(s):

Sha Jiang ◽

Ke Xu ◽

Na Zhao ◽

Shu-Xin Zheng ◽

Yan-Ping Ren ◽

...

Keyword(s):

Tension Wood ◽

Wood Formation ◽

Ethylene Evolution

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Gibberellin 20-Oxidase Gene OsGA20ox3 Regulates Plant Stature and Disease Development in Rice

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-05-12-0138-r ◽

2013 ◽

Vol 26 (2) ◽

pp. 227-239 ◽

Cited By ~ 61

Author(s):

Xue Qin ◽

Jun Hua Liu ◽

Wen Sheng Zhao ◽

Xu Jun Chen ◽

Ze Jian Guo ◽

...

Keyword(s):

Transgenic Plants ◽

Critical Role ◽

Insertion Site ◽

Insertion Mutant ◽

Wild Type Plant ◽

Wild Type ◽

Oxidase Gene ◽

Dna Insertion ◽

Flanking Sequences ◽

Plant Stature

Gibberellin (GA) 20-oxidase (GA20ox) catalyses consecutive steps of oxidation in the late part of the GA biosynthetic pathway. A T-DNA insertion mutant (17S-14) in rice, with an elongated phenotype, was isolated. Analysis of the flanking sequences of the T-DNA insertion site revealed that an incomplete T-DNA integration resulted in enhanced constitutively expression of downstream OsGA20ox3 in the mutant. The accumulation of bioactive GA1 and GA4 were increased in the mutant in comparison with the wild-type plant. Transgenic plants overexpressing OsGA20ox3 showed phenotypes similar to those of the 17S-14 mutant, and the RNA interference (RNAi) lines that had decreased OsGA20ox3 expression exhibited a semidwarf phenotype. Expression of OsGA20ox3 was detected in the leaves and roots of young seedlings, immature panicles, anthers, and pollens, based on β-glucuronidase (GUS) activity staining in transgenic plants expressing the OsGA20ox3 promoter fused to the GUS gene. The OsGA20ox3 RNAi lines showed enhanced resistance against rice pathogens Magnaporthe oryzae (causing rice blast) and Xanthomonas oryzae pv. oryzae (causing bacterial blight) and increased expression of defense-related genes. Conversely, OsGA20ox3-overexpressing plants were more susceptible to these pathogens comparing with the wild-type plants. The susceptibility of wild-type plants to X. oryzae pv. oryzae was increased by exogenous application of GA3 and decreased by S-3307 treatment. Together, the results provide direct evidence for a critical role of OsGA20ox3 in regulating not only plant stature but also disease resistance in rice.

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Genome-wide analysis of lncRNA and mRNA expression and endogenous hormone regulation during tension wood formation in Catalpa bungei

BMC Genomics ◽

10.1186/s12864-020-07044-5 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Yao Xiao ◽

Fei Yi ◽

Juanjuan Ling ◽

Guijuan Yang ◽

Na Lu ◽

...

Keyword(s):

Mrna Expression ◽

Tension Wood ◽

Wood Formation ◽

Endogenous Hormone ◽

Hormone Regulation ◽

Genome Wide Analysis ◽

Genome Wide ◽

Catalpa Bungei

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Ethylene and its interaction with other hormones in tension wood formation in Leucaena leucocephala (Lam.) de Wit

Journal of the Indian Academy of Wood Science ◽

10.1007/s13196-012-0077-0 ◽

2012 ◽

Vol 9 (2) ◽

pp. 130-139 ◽

Cited By ~ 3

Author(s):

S. Pramod ◽

Priti B. Patel ◽

Karumanchi S. Rao

Keyword(s):

Leucaena Leucocephala ◽

Tension Wood ◽

Wood Formation

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RNA-Seq analysis of differential gene expression in Betula luminifera xylem during the early stages of tension wood formation

PeerJ ◽

10.7717/peerj.5427 ◽

2018 ◽

Vol 6 ◽

pp. e5427 ◽

Cited By ~ 3

Author(s):

Miaomiao Cai ◽

Huahong Huang ◽

Fei Ni ◽

Zaikang Tong ◽

Erpei Lin ◽

...

Keyword(s):

Gene Expression ◽

Tension Wood ◽

Molecular Mechanisms ◽

Southern China ◽

Lignin Biosynthesis ◽

Wood Formation ◽

Cellulose Synthesis ◽

Early Stages ◽

Transcriptional Changes ◽

Betula Luminifera

Background Betula luminifera H. Winkler, which is widely distributed in southern China, is an economically important broadleaf tree species. However, little genomic information of B. luminifera is available, and little is known about the molecular mechanisms of wood formation in this species. Meanwhile, few efforts have focused on investigating the early transcriptional changes during tension wood formation in woody plants. Results A reference transcriptome dataset was first generated containing 45,700 Unigenes, and 35,135 (76.9%) Unigenes were annotated by a BLAST similarity search against four public databases. Then, based on an anatomical investigation, the global gene expression changes during the early stages of tension wood formation were analyzed. Gene expression profiling showed that a total of 13,273 Unigenes were differentially regulated during the early stages of tension wood formation. Most genes involved in cellulose and lignin biosynthesis were highlighted to reveal their biological importance in tension wood formation. In addition, the transcription levels of many genes involved in the auxin response pathway were significantly changed during the early stages of tension wood formation. Furthermore, 18 TFs co-expressed with key enzymes of cellulose synthesis were identified. Conclusions Our results revealed the transcriptional changes associated with TW formation and identified potential key genes in the regulation of this process. These results will help to dissect the molecular mechanism of wood formation and provide key candidate genes for marker-assisted selection in B. luminifera.

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Effect of exogenous IAA on tension wood formation by facilitating polar auxin transport and cellulose biosynthesis in hybrid poplar (Populus deltoids × Populus nigra) wood

Holzforschung ◽

10.1515/hf-2016-0078 ◽

2017 ◽

Vol 71 (2) ◽

pp. 179-188 ◽

Cited By ~ 7

Author(s):

Min Yu ◽

Kai Liu ◽

Shengquan Liu ◽

Haiyan Chen ◽

Liang Zhou ◽

...

Keyword(s):

Tension Wood ◽

Auxin Transport ◽

Hybrid Poplar ◽

Wood Formation ◽

Polar Auxin Transport ◽

Fiber Formation ◽

Pcr Analysis ◽

Cellulose Content ◽

Cellulose Biosynthesis ◽

Exogenous Iaa

Abstract Auxins as phytohormons, responsible for coordination of growing processes, also contribute to the formation of tension wood (TW) in trees, but the mechanism of this process is still unclear. In this study, it has been tried to induce TW formation in erect hybrid poplar trees (in opposite to inclined or bended trees) by treatment with exogenous indole-3-acetic acid (IAA, as one of the auxins) or N-1-naphthylphthalamic acid (NPA) as an auxin transport inhibitor. The treatment with IAA resulted in TW formation and, as expected, NPA treatment did not. The gelatinous fiber formation and higher cellulose content in the cell wall were unambiguous indicators for TW formation. Real-time polymerase chain reaction (PCR) analysis revealed that genes of PIN1, ABCB1, and AUX2 involved in polar auxin transport were highly expressed in trees treated with exogenous IAA. Moreover, expressions of cellulose biosynthesis related genes of UGP1, UGP2 and CesA13 were strongly up-regulated. These observations indicate that the accelerated intercellular polar auxin transport caused by exogenous IAA is accounted for TW formation, i.e. the signal transduction of auxin is affected, which then facilitates cellulose biosynthesis. In contrast, the transcript abundances of PIN1 and all selected cellulose synthases (CesAs) were decreased after NPA treatment via inhibiting the cellular auxin efflux with negative effects on plant’s primary growth. These results are interpreted that TW formation is closely associated with the acceleration of intercellular polar auxin transport.

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