A cDNA from grapevine (Vitis vinifera L.), which shows homology to AGAMOUS and SHATTERPROOF,is not only expressed in flowers but also throughout berry development

An AGAMOUS/SHATTERPROOF homologue (Vvmads1) was isolated from grapevine by differential display between berry and leaf mRNA. The predicted protein sequence of the full-length clone shows a high degree of homology to PLENA (77% identity) and to SHP1 and SHP2 (75% and 74% identity respectively), and is grouped with AGAMOUS/PLENA homologues when the conserved MADS and K domains are compared. Vvmads1 is expressed only in the later stages of flower development and throughout berry development, although expression is reduced after ripening commenced. When Vvmads1 was over-expressed in tobacco, the resulting plants display altered morphologies in the outer two floral whorls. In the most extreme cases, the inner whorls were surrounded by a carpelloid structure created by the modified sepals. Within these sepals were petals which had been split into sections and which were attached at the base of the flower by structures with the appearance of filaments. The results of this study suggest that Vvmads1 has a regulatory role in flower development before fertilisation and a role in fruit development after fertilisation.     

通过原位反转录研究MADS盒基因M79的时空表达模式

通过设计可以引发特定mRNA进行转录的特异引物,采用了一种新的原位反转录的方法检测mRNA,这种原位反转录的方法是把原位杂交和反转录进行有机结合的结果,其实用性能和关键步骤都已进行优化。研究表明,只要设立合适的对照原位反转录方法, 检测mRNA的灵敏度高、假阴性和假阳性率低。用这种方法对一个属于AGL2亚组的水稻(Oryza sativa L.)的MADS-盒基因M79的表达进行了分析,结果表明,在水稻从营养到生殖的各个发育阶段,M79均有表达,与平行进行的传统原位杂交的方法得到的结果类似。相对而言,原位反转录法耗时短、容易操作,可以成为一种可靠的原位定位mRNA的基本技术。     

Cloning and characterization of PhPI9 involved in floral development from Phalaenopsis Orchid

In the attempt to discover new genes involved in the floral development in monoeotyledonousin species,we have cloned and characterized the homologous PISTALLATA-like (PI-like) gone from Phalaenopsis hybrid cultivar named PhPI9 (Phalaenopsis PI STILLATA # 9).The eDNA of PhPI9 has a fragment of 834 bp and has 60% identity with the PISTILATA from Arabidopsis.The deduced amino acid sequence of PhPI9 had the typical PI-motif.It also formed a subelade with other monoeot PI-type genes in phylogenetie analysis.Southern analysis showed that PhPI9 was present in the Phalaenopsis orchid genome as a single copy.Furthermore,it was expressed only in the lip of the Phalaenopsis flower and no expression was detected in vegetative organs.Thus,as a B-function MADS-box gone,PhP19 specifies floral organ identity in orchids.     

Genetic interactions between FLM and other flowering-time genes in Arabidopsis thaliana

FLOWERING LOCUS M (FLM) is a MADS-domain gene that acts as an inhibitor of flowering in Arabidopsis. Here we describe the genetic interaction of FLM with genes in the photoperiod and autonomous flowering pathways. Although the sequence of FLM is most similar to that of FLC, FLM and FLC interact with different flowering pathways. It has been previously shown that flc lesions suppress the late-flowering phenotype of FRI-containing lines and autonomous-pathway mutants. However, flm lesions suppress the late-flowering phenotype of photoperiod-pathway mutants but not that of FRI-containing lines or autonomous-pathway mutants. Another MADS-domain flowering repressor with a mutant phenotype similar to FLM is SVP. The late-flowering phenotype of FLM over-expression is suppressed by the svp mutation, and an svp flm double mutant behaves like the single mutants. Thus FLM and SVP are in the same flowering pathway which interacts with the photoperiod pathway. Abbreviations: CO, CONSTANS; FLC, FLOWERING LOCUS C; FLM, FLOWERING LOCUS M; FRI, FRIGIDA; GI, GIGANTEA; LD, LUMINIDEPENDENS; SVP, SHORT VEGETATIVE PHASE; FCA is not an abbreviation     

小花草玉梅正常和自然变异植株的AP3-3基因研究

野生小花草玉梅(Anemone rivularis var.flore-minore)正常植株和花被片自然变异植株的外观形态差异很大,该研究以二者为材料,利用常规PCR和高效热不对称PCR(Hi-Tail PCR)技术从其正常和变异植株的基因组中各分离得到1个B类基因。序列分析证明,二者隶属于B类MADS-box基因AP3家族的旁系同源基因AP3-3分枝,分别命名为NArAP3-3(正常植株)和VArAP3-3(变异植株)。NArAP3-3基因全长3 795bp,VArAP3-3基因全长3 898bp,二者均含有1个666bp的开放阅读框(ORF),可编码221个氨基酸,具有典型的植物MADS-box基因结构,其编码肽链包含了MADS区、K区、Ⅰ区和C区。对比NArAP3-3和VArAP3-3基因的全长序列,发现VArAP3-3基因比NArAP3-3多了1段49bp的插入,且在ORF序列与NArAP3-3基因相比有4个碱基突变。对二者的全长序列、所编码的221个氨基酸及插入序列的生物信息学分析显示,二者在基因启动子、蛋白质基本性质、结构功能域、二级三级预测结构等方面均有差异,推测这些差异可能是花被片变异产生的原因之一。该研究结果为进一步探索其变异机制奠定了基础。     

MADS-box转录因子编码基因Vvrin1在草菇不同发育时期的表达分析

草菇是我国土特产出口的主要种类之一,而采后易开伞问题限制了草菇的贮藏及运输。MADS-box转录因子对植物的成熟衰老和真菌的子实体发育起到重要的调控作用。目前尚未见草菇MADS-box转录因子的相关报道。本研究通过生物信息方法及分子生物学的手段对草菇的基因组、转录组数据进行分析,获得了草菇MADS-box转录因子基因Vvrin1。该基因全长1 392bp,含2个内含子,编码419个氨基酸残基。该转录因子含有一个MADS-box结构域,序列与双孢蘑菇Agaricus bisporus、斑玉蕈Hypsizygus marmoreus和灰盖鬼伞Coprinopsis cinerea的MADS-box转录因子相似性分别为71%、67%和61%。通过表达谱数据及荧光定量PCR分析表明Vvrin1基因在草菇子实体伸长期菌柄的表达量出现高峰,具有极显著性差异（P<0.01）,推测该转录因子参与调控草菇菌柄的伸长,菌盖的开伞。这些结果为草菇成熟衰老（特别是开伞）的调控研究提供数据支持。