一個(gè)國(guó)際科學(xué)家小組近日通過分析苔蘚基因組發(fā)現(xiàn)，苔蘚基因的豐富性超乎想象,，并且具有許多獨(dú)特的變異,。根據(jù)苔蘚在植物進(jìn)化樹上的獨(dú)特位置，這一發(fā)現(xiàn)將有助于揭示植物從水生到陸生的過程,。相關(guān)論文12月13日在線發(fā)表于《科學(xué)》（Science）雜志上。
苔蘚是一種古老的植物,，它大約于4.5億年前與開花植物的祖先進(jìn)化分離開來,。在進(jìn)化道路上,，它與其它種類的植物一樣，都需要克服由水生到陸生所遭遇到的一系列挑戰(zhàn),。很多其它種植物進(jìn)化出了維管組織（vascular tissues）,，用來輸送水分和種子以在干旱的環(huán)境中存活下來；但是苔蘚并沒有進(jìn)化出維管組織及類似功能,，它似乎采取了另外的策略,。
在最新的研究中，美國(guó)華盛頓大學(xué)的發(fā)育生物學(xué)家Ralph Quatrano和研究小組,，測(cè)序了被廣泛研究的一種苔蘚P. patens的基因組,，并與水稻、開花植物擬南芥（Arabidopsis）及單細(xì)胞藻類的基因組進(jìn)行了比較,。結(jié)果發(fā)現(xiàn)這種苔蘚的基因數(shù)達(dá)到35000個(gè),，其中20%為研究人員前所未見，而且很可能是P. patens獨(dú)有的,。
Quatrano認(rèn)為這一結(jié)果非常令人吃驚,。他表示，能幫助干枯苔蘚回復(fù)生命的基因同樣也存在于其它陸生植物中,，這表明這種基因在更早的時(shí)間就已出現(xiàn),。另外，P. patens具有應(yīng)對(duì)水壓力的基因,，表明它進(jìn)化出了獨(dú)立的處理水缺乏的方法,。此外，P. patens還具有修復(fù)DNA的基因,，以應(yīng)付日照造成的損害,。Quatrano說，看起來好像是P. patens的祖先在進(jìn)化早期復(fù)制了整個(gè)基因組,，這就解放了一些基因,，使它們具有了新的功能。
美國(guó)科羅拉多大學(xué)進(jìn)化生物學(xué)家William Friedman認(rèn)為,，苔蘚基因組具有揭示植物由水生到陸生轉(zhuǎn)變過程的潛力,，這令人非常興奮。不過,，美國(guó)佛羅里達(dá)大學(xué)的進(jìn)化生物學(xué)家Pamela Soltis卻指出,，研究人員并沒有仔細(xì)分析進(jìn)化樹，而苔蘚和水稻之間的進(jìn)化差距就好比是魚和人類之間的差距,，這意味著要完全弄清植物由水生到陸生的過程,，還需要做更多的測(cè)序。（科學(xué)網(wǎng) 梅進(jìn)/編譯）
原始出處:
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Published Online December 13, 2007
Science DOI: 10.1126/science.1150646
Submitted on September 18, 2007
Accepted on November 21, 2007
The Physcomitrella Genome Reveals Evolutionary Insights into the Conquest of Land by Plants
Stefan A. Rensing 1, Daniel Lang 1, Andreas D. Zimmer 1, Astrid Terry 2, Asaf Salamov 3, Harris Shapiro 3, Tomoaki Nishiyama 4, Pierre-François Perroud 5, Erika A. Lindquist 3, Yasuko Kamisugi 6, Takako Tanahashi 7, Keiko Sakakibara 8, Tomomichi Fujita 9, Kazuko Oishi 10, Tadasu Shin-I 10, Yoko Kuroki 11, Atsushi Toyoda 11, Yutaka Suzuki 12, Shin-ichi Hashimoto 13, Kazuo Yamaguchi 14, Sumio Sugano 12, Yuji Kohara 15, Asao Fujiyama 16, Aldwin Anterola 17, Setsuyuki Aoki 18, Neil Ashton 19, W. Brad Barbazuk 20, Elizabeth Barker 19, Jeffrey L. Bennetzen 21, Robert Blankenship 5, Sung Hyun Cho 5, Susan K. Dutcher 22, Mark Estelle 23, Jeffrey A. Fawcett 24, Heidrun Gundlach 25, Kousuke Hanada 26, Alexander Heyl 27, Karen A. Hicks 28, Jon Hughes 29, Martin Lohr 30, Klaus Mayer 25, Alexander Melkozernov 31, Takashi Murata 7, David R. Nelson 32, Birgit Pils 33, Michael Prigge 23, Bernd Reiss 34, Tanya Renner 35, Stephane Rombauts 24, Paul J. Rushton 36, Anton Sanderfoot 37, Gabriele Schween 1, Shin-Han Shiu 38, Kurt Stueber 34, Frederica L. Theodoulou 39, Hank Tu 3, Yves Van de Peer 24, Paul J. Verrier 40, Elizabeth Waters 35, Andrew Wood 17, Lixing Yang 21, David Cove 41, Andrew C. Cuming 6, Mitsuyasu Hasebe 42, Susan Lucas 2, Brent D. Mishler 43, Ralf Reski 1, Igor V. Grigoriev 3, Ralph S. Quatrano 5*, Jeffrey L. Boore 44
1 Plant Biotechnology, Faculty of Biology, University of Freiburg, Schaenzlestrasse 1, D-79104 Freiburg, Germany.
2 DOE Joint Genome Institute and Lawrence Livermore National Laboratory, 2800 Mitchell Drive, Walnut Creek, CA 94598, USA.
3 DOE Joint Genome Institute and Lawrence Berkeley National Laboratory, 2800 Mitchell Drive, Walnut Creek, CA 94598, USA.
4 Advanced Science Research Center, Kanazawa University, 13-1 Takara-machi Kanazawa, 920-0934, Japan.
5 Department of Biology, Washington University, 1 Brookings Drive, St. Louis, MO 63130–4899, USA.
6 Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT, UK.
7 National Institute for Basic Biology, Okazaki 444-8585, Japan.; Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, Okazaki 444-8585, Japan.
8 School of Biological Sciences, Monash University, Clayton Campus, Melbourne, VIC 3800, Australia.
9 Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
10 Genome Biology Laboratory, Center for Genetic Resource Information, National Institute of Genetics, Mishima 411-8540, Japan.
11 RIKEN Genomic Sciences Center, Kanagawa 230-0045, Japan.
12 Laboratory of Functional Genomics, Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo 108-8639, Japan.
13 Department of Molecular Preventive Medicine, School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan.
14 Advanced Science Research Center, Kanazawa University, 13-1 Takara-machi Kanazawa, 920-0934, Japan.; Division of Life Science, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa 920-1192, Japan.
15 Genome Biology Laboratory, Center for Genetic Resource Information, National Institute of Genetics, Mishima 411-8540, Japan.; Department of Genetics, School of Life Science, The Graduate University for Advanced Studies, Mishima 411-8540, Japan.
16 RIKEN Genomic Sciences Center, Kanagawa 230-0045, Japan.; National Institute of Informatics, Tokyo 101-8403, Japan.; Department of Informatics, School of Multidisciplinary Sciences, The Graduate University for Advanced Studies, Tokyo 101-8403, Japan.
17 Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901–6509, USA.
18 Life-Science Informatics Unit, Graduate School of Information Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
19 University of Regina, 3737 Wascana Parkway, Regina, SK, Canada S4S 0A2.
20 Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA.
21 Department of Genetics, Davison Life Sciences Complex, University of Georgia, Athens, GA 30602–7223, USA.
22 Department of Genetics, Washington University, 660 South Euclid Avenue, St. Louis, MO 63108, USA.
23 Department of Biology, Indiana University, 1001 East Third Street, Bloomington, IN 47405–3700, USA.
24 VIB Department of Plant Systems Biology, Ghent University, Technologie Park 927, 9052 Ghent, Belgium.
25 MIPS/IBI Institute for Bioinformatics, GSF Research Center for Environment and Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany.
26 Department of Plant Biology, 166 Plant Biology Building, Michigan State University, East Lansing, MI 48824–1312, USA.; RIKEN Plant Science Center, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa, 230-0045, Japan.
27 Free University, Institute for Biology, Applied Genetics Neubau, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany.
28 Max-Planck Institute of Plant Breeding Research, Carl-von-Linne-Weg 10, D-50829 Cologne, Germany.; Biology Department, Kenyon College, Gambier, OH 43022, USA.
29 Pflanzenphysiologie, Justus Liebig University, Senckenbergstrasse 3, D-35390 Giessen, Germany.
30 Institute of General Botany, Johannes Gutenberg-University, D-55099 Mainz, Germany.
31 Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287–1604, USA.
32 University of Tennessee-Memphis, 101 I Molecular Science Building, 858 Madison Avenue, Memphis, TN 38163, USA.
33 Department of Bioinformatics, Biozentrum, Am Hubland,Würzburg University, D-97074 Würzburg, Germany.
34 Max-Planck Institute of Plant Breeding Research, Carl-von-Linne-Weg 10, D-50829 Cologne, Germany.
35 Biology Department, San Diego State University, North Life Sciences Room 102, 5500 Campanile Drive, San Diego, CA 92182–4614, USA.
36 Department of Biology, Gilmer Hall, 485 McCormick Road, University of Virginia, Charlottesville, VA 22903, USA.
37 Department of Plant Biology, University of Minnesota, 250 Biological Science Center, 1445 Gortner Avenue, St. Paul, MN 55108, USA.
38 Department of Plant Biology, 166 Plant Biology Building, Michigan State University, East Lansing, MI 48824–1312, USA.
39 Biological Chemistry Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.
40 Biomathematics and Bioinformatics Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.
41 Department of Biology, Washington University, 1 Brookings Drive, St. Louis, MO 63130–4899, USA.; Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT, UK.
42 National Institute for Basic Biology, Okazaki 444-8585, Japan.; Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, Okazaki 444-8585, Japan.; ERATO, Japan Science and Technology Agency, Okazaki 444-8585, Japan.
43 Department of Integrative Biology, 3060 Valley Life Sciences Building, University of California, Berkeley, CA 94720, USA.
44 DOE Joint Genome Institute and Lawrence Berkeley National Laboratory, 2800 Mitchell Drive, Walnut Creek, CA 94598, USA.; Department of Integrative Biology, 3060 Valley Life Sciences Building, University of California, Berkeley, CA 94720, USA.; Genome Project Solutions, 1024 Promenade Street, Hercules, CA 94547, USA.
* To whom correspondence should be addressed.
Ralph S. Quatrano , E-mail: [email protected]
We report the draft genome sequence of the model moss Physcomitrella patens and compare its features to those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity, loss of genes associated with aquatic environments (e.g., flagellar arms), acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability), and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant’s unique facility for reverse genetics.
