日本奈良先端科學(xué)技術(shù)學(xué)院大學(xué)生生物科學(xué)研究科的島本功教授的研究小組發(fā)現(xiàn)了決定植物在何時(shí)開花的荷爾蒙———成花素,。研究小組用水稻試驗(yàn)發(fā)現(xiàn)，成花素是由促進(jìn)水稻開花的遺傳基因Hd3a制造的蛋白質(zhì),，研究小組實(shí)際觀察到了成花素移動(dòng)到開花植物莖前端的現(xiàn)象,。
至今為止,，學(xué)術(shù)界一直認(rèn)為,，植物中存在成花素,，但科學(xué)家從未實(shí)際發(fā)現(xiàn)和觀察到成花素的存在。研究小組試驗(yàn)中在遺傳基因中植入熒光使其發(fā)光,，然后與Hd3a遺傳基因結(jié)合后導(dǎo)入水稻中，通過(guò)發(fā)光確認(rèn)了它的存在,。通常,，水稻開花要經(jīng)過(guò)50天—60天的時(shí)間，植入Hd3a遺傳基因的水稻,，只經(jīng)過(guò)15天—20天的時(shí)間即可開花,。研究小組發(fā)現(xiàn)，植入的遺傳基因Hd3a不僅存在于葉和莖等植物通道部分,，在形成花莖最頂端也存在,。
Hd3a原本只有葉子才能制造的，在通路部分以及莖部頂端幾乎觀測(cè)不到,。研究小組在試驗(yàn)中確認(rèn)了水稻莖頂部也存在Hd3a,，從而證明Hd3a蛋白質(zhì)參與了植物開花的工作。
成花素在所有植物中均存在,，因此該研究對(duì)開發(fā)鮮花生長(zhǎng)劑以及增加農(nóng)作物收成的藥劑具有重要意義,。該研究成果已刊載于19日的美國(guó)《科學(xué)》雜志網(wǎng)絡(luò)版。
英文原文： http://www.biotech.org.cn/news/news/show.php?id=50851
原始出處:
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Published Online April 19, 2007
Science DOI: 10.1126/science.1141753
Submitted on February 26, 2007
Accepted on April 6, 2007
Hd3a Protein Is a Mobile Flowering Signal in Rice
Shojiro Tamaki 1, Shoichi Matsuo 1, Hann Ling Wong 1, Shuji Yokoi 2, Ko Shimamoto 1*
1 Laboratory of Plant Molecular Genetics, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma 630-0101, Japan.
2 Laboratory of Plant Molecular Genetics, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma 630-0101, Japan; Present address: Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan.
* To whom correspondence should be addressed.
Ko Shimamoto , E-mail: [email protected]
Florigen, the mobile signal that moves from an induced leaf to the shoot apex and causes flowering, has eluded identification for the 70 years since it was first proposed. Understanding the nature of the mobile flowering signal would provide a key insight into the molecular mechanism of floral induction. Recent studies suggest that the Arabidopsis FLOWERING LOCUS T (FT) gene is a candidate for encoding florigen. Here we show that the protein encoded by Hd3a, a rice ortholog of FT, moves from the leaf to the shoot apical meristem (SAM) and induces flowering in rice. These results suggest that the Hd3a protein may be the rice florigen.
