• Animal Systematics, Evolution and Diversity
• /
• 제26권3호
• /
• pp.197-201
• /
• 2010

We sequenced the whole mitochondrial genome of Dendronephthya gigantea (Anthozoa: Octocorallia: Nephteidae), the first mitochondrial genome sequence report in the Family Nephtheidae. The mitochondrial genome of D. gigantea was 18,842 bp in length, and contained 14 protein coding genes (atp6 and 8, cox1-3, cytb, nd1-6 and 4L, and msh1), two ribosomal RNAs, and only one transfer RNA. The gene content and gene order is identical to other octocorals sequenced to date. The portion of the noncoding regions is slightly larger than the other octocorals (5.08% compared to average 3.98%). We expect that the information of gene content, gene order, codon usage, noncoding region and protein coding gene sequence could be used in the further analysis of anthozoan phylogeny.

• 통합자연과학논문집
• /
• 제4권2호
• /
• pp.113-120
• /
• 2011

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.

• 생명과학회지
• /
• 제26권4호
• /
• pp.406-413
• /
• 2016

전복은 전복속(Haliotis)에 속하며 전 세계적으로 식품산업에서 중요한 복족류 연체동물이다. 우리나라에는 6개종; 북방전복(Haliotis discus hannai), 둥근전복(Haliotis discus discus), 왕전복(Haliotis madaka), 말전복(Haliotis gigantea), 오분자기(Haliotis diversicolor diversicolor), 마대오분자기(Haliotis diversicolor supertexta)가 보고되어 있다. 이 연구에서는 우리나라 해역에 서식하는 중ㆍ대형 전복과 4종인 북방전복, 둥근전복, 왕전복, 말전복의 유전학적 유연관계를 분석하기 위하여 미토콘드리아의 cytochrome c oxidase subunit I (COI) 유전자와 Random Amplified Polymorphic DNA (RAPD) 분석법을 실시 하였다. 본 연구의 결과 COI 유전자 분석과 RAPD 분석을 활용하면 4종의 전복 중 북방전복, 둥근전복, 왕전복을 한 그룹으로 나머지 한 그룹을 말전복으로 구분하는 종 분류는 명확히 구분할 수 있었다. 이러한 결과는 전복 교잡육종을 이용한 수출용 전복 신종자 개발에 있어 주요 대상종인 전복과 4종에 대한 유전적 근연 관계를 규정함으로써 향후 교잡육종 연구의 기초 자료를 제공할 수 있을 것으로 사료된다.

• Molecules and Cells
• /
• 제42권10호
• /
• pp.693-701
• /
• 2019

Plants monitor changes in day length to coordinate their flowering time with appropriate seasons. In Arabidopsis, the diel and seasonal regulation of CONSTANS (CO) protein stability is crucial for the induction of FLOWERING LOCUS T (FT) gene in long days. FLAVIN-BINDING, KELCH REPEAT, F-BOX 1 (FKF1) and ZEITLUPE (ZTL) proteins control the shape of CO expression profile antagonistically, although regulation mechanisms remain unknown. In this study, we show that GIGANTEA (GI) protein modulates the stability and nuclear function of FKF1, which is closely related to the stabilization of CO in the afternoon of long days. The abundance of FKF1 protein is decreased by the gi mutation, but increased by GI overexpression throughout the day. Unlike the previous report, the translocation of FKF1 to the nucleus was not prevented by ZTL overexpression. In addition, the FKF1-ZTL complex formation is higher in the nucleus than in the cytosol. GI interacts with ZTL in the nucleus, implicating the attenuation of ZTL activity by the GI binding and, in turn, the sequestration of FKF1 from ZTL in the nucleus. We also found that the CO-ZTL complex presents in the nucleus, and CO protein abundance is largely reduced in the afternoon by ZTL overexpression, indicating that ZTL promotes CO degradation by capturing FKF1 in the nucleus under these conditions. Collectively, our findings suggest that GI plays a pivotal role in CO stability for the precise control of flowering by coordinating balanced functional properties of FKF1 and ZTL.

• BMB Reports
• /
• 제50권5호
• /
• pp.235-236
• /
• 2017

The circadian clock is an internal system that is synchronized by external stimuli, such as light and temperature, and influences various physiological and developmental processes in living organisms. In the model plant Arabidopsis, transcriptional, translational and post-translational processes are interlocked by feedback loops among morning- and evening-phased genes. In a post-translational loop, plant-specific single-gene encoded GIGANTEA (GI) stabilize the F-box protein ZEITLUPE (ZTL), driving the targeted-proteasomal degradation of TIMING OF CAB EXPRESSION 1 (TOC1) and PSEUDO-RESPONSE REGULATOR 5 (PRR5). Inherent to this, we demonstrate the novel biochemical function of GI as a chaperone and/or co-chaperone of Heat-Shock Protein 90 (HSP90). GI prevents ZTL degradation as a chaperone and facilitates ZTL maturation together with HSP90/HSP70, enhancing ZTL activity in vitro and in planta. GI is known to be involved in a wide range of physiology and development as well as abiotic stress responses in plants, but it could also interact with diverse client proteins to increase protein maturation. Our results provide evidence that GI helps proteostasis of ZTL by acting as a chaperone and a co-chaperone of HSP90 for proper functioning of the Arabidopsis circadian clock.

• 원예과학기술지
• /
• 제29권2호
• /
• pp.135-143
• /
• 2011

In the Doritaenopsis hybrid, like most of the orchid species and hybrids, temperature is crucial for the vegetative-to-reproductive transition, and low temperature is required for bud differentiation. To understand the molecular mechanism of this process, an orchid GIGANTEA (GI) gene, DhGI1, was isolated and characterized by using the rapid amplification of cDNA ends (RACE) PCR technique. Sequence analysis showed that the full-length cDNA is 4,022 bp with a major open reading frame of 3,483 bp, and the amino acid sequence showed high similarity to GI proteins in Zea mays, Oryza sativa, Arabidopsis thaliana and other plants. Semi-quantitative RT-PCR revealed that DhGI1 was expressed throughout development and could be detected in roots, stems, leaves, peduncles and flower buds. The expression level of DhGI1 was higher when the plants were flowering at low temperature (22/$18^{\circ}C$ day/night) than the other growth stages. Further analysis indicated that the accumulation of DhGI1 transcripts was significantly increased at low temperature, and concomitantly, initiation of the peduncle was observed. However, DhGI1 levels were low under high temperature (30/$25^{\circ}C$) conditions, and flower initiation was inhibited. These results indicate that the expression of DhGI1 is regulated by low temperature and that DhGI1 may play an important role in inflorescence initiation in this Doritaenopsis hybrid at low temperatures.

• 한국동물학회:학술대회논문집
• /
• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
• /
• pp.10-10
• /
• 1999

No Abstract, See Full Text