HAG1 gene was isolated from the floral organs of Hyacinthus orientalis L. by using RT-PCR. Sequence analysis showed that this gene was homologous to AGAMOUS. Northern hybridization indicated that HAG1 was specifically...HAG1 gene was isolated from the floral organs of Hyacinthus orientalis L. by using RT-PCR. Sequence analysis showed that this gene was homologous to AGAMOUS. Northern hybridization indicated that HAG1 was specifically expressed in floral organs using 3’ end of HAG1 as a probe. Further, transcript of this gene was not detected in differentiating tepals induced by lower concentration of hormones, however, it was detected in differentiating stemans by higher concentration of hormones in vitro. It is possible that there is a close relationship between the concentration of hormones, homeotic genes and identities of floral organs.展开更多
本文对风信子(Hyacinthus orientalis L.)与拟南芥(Arabidopsis thaliana)AGL6的同源MADS盒基因HoAGL6进行了功能研究.基因表达分析结果显示,HoAGL6 mRNA在花序芽、花被、心皮和胚珠中积累,但未出现于雄蕊、营养器官的叶和鳞片中.这说明...本文对风信子(Hyacinthus orientalis L.)与拟南芥(Arabidopsis thaliana)AGL6的同源MADS盒基因HoAGL6进行了功能研究.基因表达分析结果显示,HoAGL6 mRNA在花序芽、花被、心皮和胚珠中积累,但未出现于雄蕊、营养器官的叶和鳞片中.这说明HoAGL6参与了风信子花的形成,以及花被和子房的发育.HoAGL6在拟南芥(Arabidopsis thaliana)中异位表达,转基因植株表现为株型矮小,极度提早开花,并失去花序的不确定性.因此,HoAGL6参与了开花时间调节.另外,35S::HoAGL6转基因拟南芥植株频繁出现器官同源转化,包括花萼、花瓣和叶片转化为心皮状结构或子房结构,且雄蕊缺失或数目减少.此结果表明,在转化植株中HoAGL6参与了花器官特性决定.进一步的研究表明,在35S::HoAGL6的拟南芥转化植株中显著提高了开花时间调节基因SOC1和花分生组织特征基因LFY的表达水平,并且HoAGL6的异位表达也在叶片中激活了花器官特征基因AG和SEP1的表达.这些结果支持在拟南芥中HoAGL6通过促进SOC1和LFY的表达来调节开花时间,以及通过激活AG和SEP1参与了花器官发育.展开更多
MADS-box genes are involved in floral organ development. Here we report that an AGL6(Agamous-like 6)-like MADS-box gene, HoAGL6, was isolated from Hyacinthus orientalis L. Expression pattern analy-sis demonstrated tha...MADS-box genes are involved in floral organ development. Here we report that an AGL6(Agamous-like 6)-like MADS-box gene, HoAGL6, was isolated from Hyacinthus orientalis L. Expression pattern analy-sis demonstrated that HoAGL6 transcript was detected in inflorescence buds, tepals, carpels and ovules, but not in stamina, leaves or scales. Transgenic Arabidopsis plants ectopically expressing HoAGL6 exhibited novel phenotypes of significantly reduced plant size, extremely early flowering, and losing inflorescence indeterminacy. In addition, wide homeotic conversion of sepals, petals, and leaves into carpel-like or ovary structures, and disappearance or number reduction of stamens in 35S::HoAGL6 Arabidopsis plants were also observed. RT-PCR analysis indicated that the expressions of flowering time gene SOC1 and flower meristem identity gene LFY were significantly up-regulated in 35S::HoAGL6 transgenic Arabidopsis plants, and the expression levels of floral organ identity genes AG and SEP1 in leaves were also elevated. These results indicated that HoAGL6 was involved in the regulation of flower transition and flower organ formation.展开更多
文摘HAG1 gene was isolated from the floral organs of Hyacinthus orientalis L. by using RT-PCR. Sequence analysis showed that this gene was homologous to AGAMOUS. Northern hybridization indicated that HAG1 was specifically expressed in floral organs using 3’ end of HAG1 as a probe. Further, transcript of this gene was not detected in differentiating tepals induced by lower concentration of hormones, however, it was detected in differentiating stemans by higher concentration of hormones in vitro. It is possible that there is a close relationship between the concentration of hormones, homeotic genes and identities of floral organs.
文摘MADS-box genes are involved in floral organ development. Here we report that an AGL6(Agamous-like 6)-like MADS-box gene, HoAGL6, was isolated from Hyacinthus orientalis L. Expression pattern analy-sis demonstrated that HoAGL6 transcript was detected in inflorescence buds, tepals, carpels and ovules, but not in stamina, leaves or scales. Transgenic Arabidopsis plants ectopically expressing HoAGL6 exhibited novel phenotypes of significantly reduced plant size, extremely early flowering, and losing inflorescence indeterminacy. In addition, wide homeotic conversion of sepals, petals, and leaves into carpel-like or ovary structures, and disappearance or number reduction of stamens in 35S::HoAGL6 Arabidopsis plants were also observed. RT-PCR analysis indicated that the expressions of flowering time gene SOC1 and flower meristem identity gene LFY were significantly up-regulated in 35S::HoAGL6 transgenic Arabidopsis plants, and the expression levels of floral organ identity genes AG and SEP1 in leaves were also elevated. These results indicated that HoAGL6 was involved in the regulation of flower transition and flower organ formation.