Molecular characterization and functional analysis of barley semi-dwarf mutant Riso no. 9265.
Molecular characterization and functional analysis of barley semi-dwarf mutant Riso no. 9265.
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大麦半矮化突变体Riso no.的分子表征及功能分析
DOI：
10.1186/s12864-015-2116-x
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发表时间：
2015-11-14
期刊：
影响因子：
4.4
通讯作者：
Zhang G
中科院分区：
文献类型：
--
作者：
Jia Q;Li C;Shang Y;Zhu J;Hua W;Wang J;Yang J;Zhang G
sdw1/denso是大麦育种中最重要且最有用的半矮秆基因之一。据报道至少有4种sdw1/denso等位基因，HvGA20ox2被认为是候选基因。到目前为止，研究结果尚未明确证明sdw1/denso与HvGA20ox2之间的遗传关系。
在本研究中，从一个半矮秆突变体Riso 9265的sdw1位点鉴定出包括HvGA20ox2和Mloc_56463基因在内的Morex_contig_40861完全缺失。与野生型Bomi相比，该突变体中编码赤霉素生物合成的基因（HvGA20ox1和HvGA3ox2）表达增加，而赤霉素分解代谢基因HvGA2ox3的表达降低。HvGA20ox2的过表达能够挽救半矮秆表型并提高赤霉素浓度。
我们证实了一种赤霉素生物合成酶HvGA20ox2，作为赤霉素20 - 氧化酶，是sdw1/denso半矮秆性状的功能基因。HvGA20ox2的缺失部分由HvGA20ox1补偿，并且进一步受到赤霉素的反馈调节。我们还推断sdw1/denso等位基因本身由于其内源赤霉素浓度降低而影响抽穗期延迟。
本文的网络版（doi:10.1186/s12864 - 015 - 2116 - x）包含补充材料，授权用户可获取。
Backgroundsdw1/densois one of the most important and useful semi-dwarf genes in barley breeding. At least foursdw1/densoalleles have been reported andHvGA20ox2is considered as the candidate gene. Up to date, results of studies have not univocally proven the genetic relationship betweensdw1/densoandHvGA20ox2.ResultsIn the present study, a complete deletion of Morex_contig_40861 including bothHvGA20ox2and Mloc_56463 genes was identified at thesdw1locus from a semi-dwarf mutant Riso no. 9265. Expression of the genes encoding gibberellin biosynthesis (HvGA20ox1andHvGA3ox2) were increased in the mutant compared to the wild type Bomi, while the expression of GA catabolic geneHvGA2ox3was decreased. Over-expression ofHvGA20ox2could rescue the semi-dwarf phenotype and increase GAs concentration.ConclusionsWe confirmed that a GA biosynthetic enzyme HvGA20ox2, acted as GA 20-oxidase, is the functional gene for thesdw1/densosemi-dwarfism. Lose ofHvGA20ox2is partially compensated byHvGA20ox1and further feedback is regulated by gibberellin. We also deduced that thesdw1/densoallele itself affects later heading owing to its reduced endogenous GAs concentration.