3月18日的Nature上，發(fā)表了來自Broad研究所,，阿姆斯特丹大學(xué),，加州大學(xué)，西班牙,，法國等國際研究團隊經(jīng)過基因組對比分析發(fā)現(xiàn)鐮菌屬真菌宿主選擇的遺傳差異,。
鐮菌屬真菌是真菌中的重要類群，其分布廣泛,，可生存在土壤等多種環(huán)境中,。鐮孢菌的許多種類是重要的植物病原菌， 如由尖孢鐮孢菌等鐮孢菌侵染引起的瓜類枯萎病是瓜類生產(chǎn)上的主要病害之一,， 尤以黃瓜,、西瓜和甜瓜上的危害最為嚴(yán)重。
有些鐮孢菌屬真菌宿主選擇范圍很寬,，而有些則選擇范圍較窄,。為了了解不同菌種對宿主選擇的分子機制，科學(xué)家們對三個宿主選擇范圍有寬有窄的鐮菌屬真菌（其中兩個剛完成測序）Fusarium graminearum, Fusarium verticillioides 和 Fusarium oxysporum f. sp.lycopersici進行了比較基因組研究,，這些基因組比對是為了解是驅(qū)動這些差異的線索,。
科學(xué)家們研究分析表明，在鐮菌屬真菌基因組的種屬特異性序列占據(jù)整個基因組的1/4,，包含4個同源染色體,。這個種屬特異性的區(qū)域包含大量的轉(zhuǎn)座子和有進化痕跡的基因，這些基因與致病性有很大關(guān)系,?？茖W(xué)家們嘗試將兩個菌種在標(biāo)準(zhǔn)生長介質(zhì)上混合（將來自一個尖孢鐮刀菌番茄病原體的兩個完整染色體轉(zhuǎn)移）,，就能將一個非致病菌種變成一個致病菌種。
這些發(fā)現(xiàn)為了解宿主范圍及致病性的演化提供了線索,。（生物谷Bioon.com）
生物谷推薦原文出處：
Nature doi:10.1038/nature08850
Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium
Li-Jun Ma1,26, H. Charlotte van der Does2,26, Katherine A. Borkovich3, Jeffrey J. Coleman4, Marie-Josée Daboussi5, Antonio Di Pietro6, Marie Dufresne5, Michael Freitag7, Manfred Grabherr1, Bernard Henrissat8, Petra M. Houterman2, Seogchan Kang9, Won-Bo Shim10, Charles Woloshuk11, Xiaohui Xie12, Jin-Rong Xu11, John Antoniw13, Scott E. Baker14, Burton H. Bluhm11, Andrew Breakspear15, Daren W. Brown16, Robert A. E. Butchko16, Sinead Chapman1, Richard Coulson17, Pedro M. Coutinho8, Etienne G. J. Danchin8,27, Andrew Diener18, Liane R. Gale15, Donald M. Gardiner19, Stephen Goff20, Kim E. Hammond-Kosack13, Karen Hilburn15, Aurélie Hua-Van5, Wilfried Jonkers2, Kemal Kazan19, Chinnappa D. Kodira1,27, Michael Koehrsen1, Lokesh Kumar1, Yong-Hwan Lee21, Liande Li3, John M. Manners19, Diego Miranda-Saavedra22, Mala Mukherjee10, Gyungsoon Park3, Jongsun Park21, Sook-Young Park9,27, Robert H. Proctor16, Aviv Regev1, M. Carmen Ruiz-Roldan6, Divya Sain3, Sharadha Sakthikumar1, Sean Sykes1, David C. Schwartz23, B. Gillian Turgeon24, Ilan Wapinski1, Olen Yoder25, Sarah Young1, Qiandong Zeng1, Shiguo Zhou23, James Galagan1, Christina A. Cuomo1, H. Corby Kistler15 & Martijn Rep2
Fusarium species are among the most important phytopathogenic and toxigenic fungi. To understand the molecular underpinnings of pathogenicity in the genus Fusarium, we compared the genomes of three phenotypically diverse species: Fusarium graminearum, Fusarium verticillioides and Fusarium oxysporum f. sp. lycopersici. Our analysis revealed lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes and account for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity, indicative of horizontal acquisition. Experimentally, we demonstrate the transfer of two LS chromosomes between strains of F. oxysporum, converting a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in F. oxysporum. These findings put the evolution of fungal pathogenicity into a new perspective.
