http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 주제어 : Brassinosteroid (BR) (검색결과 6 건)
- 무료
- 기관 내 무료
- 유료
-
Park Chan-Ho,Yeon Ju Park,Ji‑Hyun Youn,노지희,김성기 한국식물학회 2023 Journal of Plant Biology Vol.66 No.2
The crosstalk mechanism regulating content and signal transduction between brassinosteroids (BRs) and salicylic acid (SA) for plant defense was investigated in Arabidopsis. Compared to the wild type, an increased bacterial resistance was observed in bzr1-1D, a dominant mutant of the BR transcription factor BZR1. In bzr1-1D, SA biosynthetic gene ICS1 expression and endogenous SA content greatly increased upon Pst DC3000 infection, and the direct binding of BZR1 to the ICS1 promoter was confirmed through EMSA and ChIP. In bzr1-1D where NPR1 expression was almost absent, expression of PR genes was increased, and both BZR1 and PR5 expressions increased after SA treatment. EMSA and ChIP verified that BZR1 binds directly to the cis-element present in the PR5 promoter and a pull-down assay showed that TGAs, SA transcription factors upstream of PR genes, interact with BZR1 at the protein level. Crude enzyme assays demonstrated that BR C-6 oxidase activity, a CYP85A1 function, greatly increased during Pst DC3000 infection. In the tga1 tga4 double mutant lacking SA transcription factors TGA1 and TGA4, BR biosynthetic gene CYP85A1 expression was significantly reduced. EMSA and ChIP confirmed that both TGA1 and TGA4 bind to the cis-element present in the CYP85A1 promoter, and castasterone (CS), a bio-active BR, was significantly reduced in tga1 tga4. Taken together, the upregulation of ICS1 expression by BZR1 and CYP85A1 expression by TGA1/4 mutually enhanced endogenous level of BR and SA in Arabidopsis. Furthermore, TGAs and BZR1 interaction at the protein level induces SA-induced immunity through the upregulation of PR5 expression, increasing bacterial resistance in the plant. These results explain the mutual control mechanisms of the synergistic effects BR and SA have on plant defense and confirm BR’s effect on plant defense and growth promotion in A. thaliana.
-
Brassinosteroid reduces ABA accumulation leading to the inhibition of ABA-induced stomatal closure
Ha, Yun Mi,Shang, Yun,Yang, Dami,Nam, Kyoung Hee Elsevier 2018 Biochemical and biophysical research communication Vol.504 No.1
<P><B>Abstract</B></P> <P>Proper regulation of stomatal movement in response to various environmental stresses or developmental status is critical for the adaptation of many plant species to land. In plants, abscisic acid (ABA)-induced stomatal closure is a well-adapted method of regulating water status. In addition to ABA, we previously showed that plant-specific steroidal hormone, brassinosteroid (BR), also induces stomatal closure; however, BR modulates ABA-induced stomatal closure negatively at high concentrations. In this study, we further investigated the cross-talk between ABA and BR in relation to stomatal movement. In contrast to previous reports that ABA-induced stomatal closure was inhibited by brassinolide (BL), the most active BR, we showed that BL-induced stomatal closure was enhanced by ABA, indicating that the sequence of ABA or BL treatments led to different results. We found that this phenomenon occurred because the guard cells still had the capacity to be closed further by ABA, as the degree of stomatal closure by BL was always less than that by ABA. We also found that BL-induced stomatal closure required Open Stomata 1 (OST1) activity and the induced expression of <I>OST1</I> was indifferent to the sequence of ABA and/or BL treatments. In addition, we examined the underlying mechanism by which inhibition of ABA-induced stomatal closure by BL occurred. We revealed that the downregulation of ABA-biosynthetic genes by BL resulted in a lower accumulation of ABA. These results suggested that the regulation of stomatal movement is finely controlled by the combined effects of plant hormones, ABA and BR.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ABA strengthened BL-induced stomatal closure. </LI> <LI> Expression of <I>OST1</I> was induced by BL, and BL-induced stomatal closure required OST1. </LI> <LI> Inhibition of ABA-induced stomatal closure by BR was due to reduced ABA accumulation. </LI> </UL> </P>
-
Effect of Lysophosphatidylethanolamine and Brassinosteroids on Development of Arabidopsis Roots
So yoon Jeong,Chan Ho Park,Min-Kyun Kim,Sang jun Nam,홍지흔,김성기 한국식물학회 2012 Journal of Plant Biology Vol.55 No.2
Exogenously applied lysophosphatidylethanolamine (LPE) increased the growth of primary roots and the formation of lateral roots in Arabidopsis thaliana. In the presence of brassinolide, lateral root formation induced by LPE was enhanced, implying that both LPE and brassinosteroids (BR) interact positively in the development of Arabidopsis roots. Co-treatment with LPE and BRs increased the bending activity in the rice lamina inclination assay compared to that when BRs were applied alone, suggesting that LPE seems to exert its activity via BRs activity. RTPCR revealed that LPE did not alter the expressions of genes involved in the biosynthesis of BRs but did activate the expressions of BR signaling genes in A. thaliana. In a BR-insensitive mutant, bri1, enhanced gravitropic response by LPE in wild-type A. thaliana was diminished. In conclusion,LPE is a positive regulator for the growth and development of Arabidopsis roots, and this process seems to be enhanced by BR signaling rather than by increase in endogenous levels of BRs in A. thaliana.
-
Brassinosteroids modulate ABA-induced stomatal closure in Arabidopsis
Ha, Yunmi,Shang, Yun,Nam, Kyoung Hee Oxford University Press 2016 Journal of experimental botany Vol.67 No.22
<▼1><P><B>Highlight</B></P><P>Brassinosteroids alone promote stomatal closure, and in combination with ABA, they positively and negatively modulate ABA-induced stomatal closure in Arabidopsis.</P></▼1><▼2><P>Stomatal movement in response to water availability is an important physiological process in the survival of land plants. The plant hormone abscisic acid (ABA) and brassinosteroids (BRs) regulate stomatal closure. The physiological functions of ABA and BRs, including germination, cell elongation and stomatal movement, are generally known to be antagonistic. Here, we investigated how BRs affect stomatal movement alone and in combination with ABA. We demonstrate that brassinoslide (BL), the most active BR, promotes stomatal closure in an ABA-independent manner. Interestingly, BL also inhibited ABA-induced stomatal closure when a high concentration of BL was added to ABA. Furthermore, we found that the induction of some genes for reactive oxygen species (ROS) generation by ABA (<I>AtrbohD</I>, <I>NIA1</I> and <I>NIA2</I>) and subsequent ROS production were repressed by BL treatment. The BR signaling mutant <I>bri1-301</I> failed to inhibit ABA-induced stomatal closure upon BL treatment. However, <I>BRI1</I>-overexpressing transgenic plants were hypersensitive to ABA during stomatal closure, and BL reversed ABA-induced stomatal closure more completely than in wild type plants. Taken together, these results suggest that BRs can positively and negatively modulate ABA-induced stomatal closure. Therefore, interactions between ABA and BR signaling are important for the regulation of stomatal closure.</P></▼2>
-
Jeehee Roh,Chan‑Ho Park,Seung‑Hyun Son,Seong‑Ki Kim 한국식물학회 2023 Journal of Plant Biology Vol.66 No.3
Expression of ABA-deficient 2 (ABA2) gene involved in ABA biosynthesis was downregulated in bes1-D, but upregulated in bes1-KO. Hence, the expression of ABA2 is negatively controlled by the BES1 transcription factor of brassinosteroid signaling in Arabidopsis thaliana. BES1 is directly bound to the E-box sequences in the promoter of ABA2, which reduced the endogenous levels of ABA in the plant. The seeds of aba2-1 and bes1-KO were larger and smaller, respectively, than those of the wild type. In bes1-KO × aba2-1, the reduced seed size in bes1-KO was partly restored to the seed size in aba2-1. Hence, BES1-mediated regulation of seed size is an upstream process for the homeostasis of endogenous ABA to control the seed size. BES1 suppressed the expression of ABA Insensitive 5 (ABI5), a major transcription factor gene in ABA signaling that determines the seed size. It is directly bound to the promoter of ABI5 by BES1-induced downregulation of ABI5. The expression of SHORT HYPOCOTYL UNDER BLUE1, MINISEED3, and HAIKU2 as positively regulatory genes determining the seed size was activated, increasing the seed size in bes1-D. Conclusively, brassinosteroid signaling through BES1 downregulated both the biosynthesis and signaling of ABA, which increased the seed size in Arabidopsis.
-
KISS연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
