Function of a short spacer between rice EPSP synthase and rps20 genes.

水稻 EPSP 合酶和 rps20 基因之间短间隔区的功能。

• 批准号: 11660001
• 负责人: KISHIMA Yuji
• 金额: $ 2.05万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11660001/
• 关键词: rice; 5-enolpyruvylshikimate-3-phosphate (EPSP synthase); ribosome protein S 20 (rps20); short-spacer; Antisense RNA; mutation rate; s-enolpyruvylshikimate-3-phosphate(epsp)合成酵素遺伝子; 種分化

We mapped the fragments with sequence (s) expressed in the rice callus onto a physical map for a 328-kb BAC contig around the rice waxy locus. Among the hybridized fragments, we attempted to characterize strongly hybridized fragments located in a region about 45 kb downstream of waxy. The fragments were found to contain two housekeeping genes encoding 5-enolpyruvylshikimate-3-phosphate synthase (EPSPs) and ribosomal protein small subunit 20 (rps20). Interestingly, these housekeeping genes are adjoined, with only a 303-bp spacer, and are directed in a tail-to-tail orientation. Nearly-full-length cDNA clones of the two genes were obtained by screening the callus cDNA library. A clone for the EPSPs gene possessed an open reading frame of 1683 bp encoding a deduced 561-amino-acid (aa) polypeptide that is the first expressed gene identified in rice using this method. EPSPs is a key enzynae on the shikimate pathway and is localized in the plastids of higher plants. This enzyme is known to be … More targeted by glyphosate, which has been employed as a nonselective herbicide. A gene for the rice rps20 peptide had previously been isolated, and our rps2O cDNA clone completely matched the registered sequence for this peptide. Northern blotting analyses were conducted using blots of total RNAs extracted from roots, seedlings, spikelets and anthers of Japonica and Indica rice strains. The 2.2-kb transcript of the EPSPs gene was easily detected in RNA samples from roots, seedlings and spikelets, but not the RNA from anthers. A 0.75-kb rps20 transcript was detected in all the tissues we examined, although the expression in roots from both rice strains was very weak. We have examined an extent of the transcript of either gene. These transcripts proceeded beyond the spacer ; the expression of the other gene might be modified by the antisense RNA from the opposite gene, resulting in double-stranded RNA, which might act as a trigger for RNA degradation in the mechanism called post-transcriptional gene silencing. The short spacer found here is uncommon in the nuclear gene organization in higher plants. This segment may have evolutionary implications about spacer expansion or contraction in the plant nuclear genome, and may play a role in gene regulation caused by the opposite gene transcript. Less

我们用在水稻愈伤组织中表达的序列映射到物理图上，以在米蜡基因座周围的328-kb BAC重叠群。在杂交片段中，我们试图表征位于蜡状下游约45 kb的区域中的强杂交片段。发现这些片段包含两个编码5-烯醇的3-磷酸盐合酶（EPSP）和核糖体蛋白小亚基20（RPS20）的管家基因。有趣的是，这些管家基因仅相邻，只有303 bp的垫片，并以尾巴为导向。通过筛选愈伤组织cDNA文库获得了两个基因的几乎完整长度的cDNA克隆。 EPSP基因的克隆具有1683 bp的开放式阅读框，编码推导的561-氨基酸（AA）多肽，该多肽是使用此方法在大米中鉴定出的第一个表达基因。 EPSP是Shikimate途径上的关键乙烯，并且位于较高植物的塑料中。已知这种酶是……更受草甘膦的靶向，该酶被用作非选择性除草剂。先前已经分离出了水稻RPS20肽的基因，我们的RPS2O cDNA克隆完全匹配该肽的注册序列。使用从根，幼苗，尖刺以及Japonica和Indica水稻菌株中提取的总RNA的印迹进行了北印迹分析。 EPSPS基因的2.2-kb转录本很容易在根，幼苗和尖峰的RNA样品中检测到，但没有花药的RNA。在我们检查的所有组织中检测到0.75-KB RPS20转录本，尽管两种水稻菌株的根表达都非常弱。我们已经检查了两个基因的转录本的程度。这些成绩单超出了间隔者。另一个基因的表达可能是通过反对基因的反义RNA来改变的，导致双链RNA，这可能是称为转录后基因沉默的机制中RNA降解的触发因素。此处发现的短间隔物在高等植物的核基因组织中并不常见。该细分市场可能对植物核基因组的间隔膨胀或收缩的进化含义，并且可能在相反基因转录引起的基因调节中起作用。较少的

项目成果

H.Nagano: "Structural differences in the vicinity of the waxy locus among Oryza species with AA-genome : identification of variable regions"Theoretical and Applied Genetics. (in press).

H.Nagano：“具有 AA 基因组的稻种间蜡状位点附近的结构差异：可变区的识别”理论与应用遗传学。

H.Nagano: "DNA sequences homologous to rice tungro bacilliform virus (RTBV) present in the rice genome."Rice Genetics Newsletter. 17. 103-105 (2000)

H.Nagano：“与水稻基因组中存在的水稻东格罗杆状病毒 (RTBV) 同源的 DNA 序列。”水稻遗传学通讯。

H.Nagano: "Genomic organization of the 260 kb surrounding the waxy locus in a Japonica rice."Genome. 42. 1121-1126 (1999)

H.Nagano：“粳稻蜡质基因座周围 260 kb 的基因组组织。”基因组。

H.Nagano: "Organization of the 260kb of the vicinity of the waxy locus"Rice Genetics Newsletter. 15. 167-169 (1998)

H.Nagano：“蜡状基因座附近 260kb 的组织”水稻遗传学通讯。

Y.Kishima et al.: "Structural conservation of the transposon Tam3 family in Antirrhinum majus and estimation of the number of copies abel to transpose."Plant Molecular Biology. 39. 299-308 (1999)

Y.Kishima 等人：“金鱼草中转座子 Tam3 家族的结构保守性和转座拷贝数的估计。”植物分子生物学。