Earticle

초록

영어

Brassinosteroids (BRs) are plant steroid hormones that play essential roles in growth and development. Mutations in BR-signaling pathways cause defective in growth and development like dwarfism, male sterility, abnormal vascular development and photomorphogenesis. Transition from vegetative to reproductive growth is a critical phase change in the development of a flowering plant. In a screen of activation-tagged Arabidopsis, we identified a mutant named abz126 that displayed longer hypocotyls when grown in the dark on MS media containing brassinazole (Brz), an inhibitor of BRs biosynthesis. We have cloned the mutant locus using adapter ligation PCR walking and identified that a single T-DNA had been integrated into the ninth exon of the GIGANTEA (GI) gene, involved in controling flowering time. This insertion resulted in loss-of-function of the GI gene and caused the following phenotypes: long petioles, tall plant height, many rosette leaves and late flowering. RT-PCR assays on abz126 mutant showed that the T-DNA insertion in GIGANTEA led to the loss of mRNA expression of the GI gene. In the hormone dose response assay, abz126 mutant showed: 1) an insensitivity to paclobutrazole (PAC), 2) an altered response with 6-benzylaminopurine (BAP) and 3) insensitive to Brassinolide (BL). Based on these results, we propose that the late flowering and tall phenotypes displayed by the abz126 mutant are caused by a loss-of-function of the GI gene associated with brassinosteroid hormone signaling.

목차

Abstract
 1. Introduction
 2. Experimental Section
  2.1. Plant material and growth conditions
  2.2. Isolation of an abz126 mutant
  2.3. Determination of T-DNA insertion site
  2.4. RNA isolation and cDNA synthesis
  2.5. RT-PCR expression analysis
  2.6. Hormone assay
 3. Result
  3.1. Screening of abz126 mutant in T-DNA tagging lines
  3.2. Identification of T-DNA Insertion Site
  3.3. Expression of GI and Neighboring Genes
  3.4. Knock-out of the GI Gene: Effects on Plant Size and Flowering Time
  3.5. abz126 responds differently to exogenous BL treatment.
 4. Discussion
 References

키워드

저자

• Indeok Hwang [ Department of Biotechnology, Chosun University ]
• Jaeyoung Park [ Department of Biotechnology, Chosun University ]
• Beomgi Lee [ Department of Biotechnology, Chosun University ]
• Hyeonsook Cheong [ Department of Biotechnology, Chosun University ] Corresponding author

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  통합자연과학논문집(구 조선자연과학논문집) [Journal of Integrative Natural Science]

• 간기

  계간

• pISSN

  2005-1042

• 수록기간

  2008~2026

• 등재여부

  KCI 등재

• 십진분류

  KDC 405 DDC 505