Genome evolution following host jumps in the Irish potato famine pathogen lineage     

Raffaele S  Farrer RA  Cano LM  Studholme DJ  MacLean D  Thines M  Jiang RH  Zody MC  Kunjeti SG  Donofrio NM  Meyers BC  Nusbaum C  Kamoun S 《Science (New York, N.Y.)》2010,330(6010):1540-1543

Many plant pathogens, including those in the lineage of the Irish potato famine organism Phytophthora infestans, evolve by host jumps followed by specialization. However, how host jumps affect genome evolution remains largely unknown. To determine the patterns of sequence variation in the P. infestans lineage, we resequenced six genomes of four sister species. This revealed uneven evolutionary rates across genomes with genes in repeat-rich regions showing higher rates of structural polymorphisms and positive selection. These loci are enriched in genes induced in planta, implicating host adaptation in genome evolution. Unexpectedly, genes involved in epigenetic processes formed another class of rapidly evolving residents of the gene-sparse regions. These results demonstrate that dynamic repeat-rich genome compartments underpin accelerated gene evolution following host jumps in this pathogen lineage.  相似文献   

Signatures of adaptation to obligate biotrophy in the Hyaloperonospora arabidopsidis genome   总被引：2，自引：0，他引：2  

Baxter L  Tripathy S  Ishaque N  Boot N  Cabral A  Kemen E  Thines M  Ah-Fong A  Anderson R  Badejoko W  Bittner-Eddy P  Boore JL  Chibucos MC  Coates M  Dehal P  Delehaunty K  Dong S  Downton P  Dumas B  Fabro G  Fronick C  Fuerstenberg SI  Fulton L  Gaulin E  Govers F  Hughes L  Humphray S  Jiang RH  Judelson H  Kamoun S  Kyung K  Meijer H  Minx P  Morris P  Nelson J  Phuntumart V  Qutob D  Rehmany A  Rougon-Cardoso A  Ryden P  Torto-Alalibo T  Studholme D  Wang Y  Win J  Wood J  Clifton SW  Rogers J  Van den Ackerveken G  Jones JD 《Science (New York, N.Y.)》2010,330(6010):1549-1551

Many oomycete and fungal plant pathogens are obligate biotrophs, which extract nutrients only from living plant tissue and cannot grow apart from their hosts. Although these pathogens cause substantial crop losses, little is known about the molecular basis or evolution of obligate biotrophy. Here, we report the genome sequence of the oomycete Hyaloperonospora arabidopsidis (Hpa), an obligate biotroph and natural pathogen of Arabidopsis thaliana. In comparison with genomes of related, hemibiotrophic Phytophthora species, the Hpa genome exhibits dramatic reductions in genes encoding (i) RXLR effectors and other secreted pathogenicity proteins, (ii) enzymes for assimilation of inorganic nitrogen and sulfur, and (iii) proteins associated with zoospore formation and motility. These attributes comprise a genomic signature of evolution toward obligate biotrophy.  相似文献   

马铃薯晚疫病菌小种特异无毒基因候选表达序列的cDNA-AFLP鉴定   总被引：5，自引：0，他引：5  

郭军  屈冬玉  王晓武  金黎平  谢开云  Rays H.Y.Jiang  Francine Govers 《园艺学报》2005,32(1):44-48

 利用具有6个无毒基因不同表现型且处于萌发中的静孢子时期的马铃薯晚疫病菌构建4个混合池, 通过cDNA2AFLP分析, 共获得85个与无毒基因相关的差异表达片段, 其中与无毒基因Avr1、Avr2、Avr3-Avr10-Avr11、Avr4 相关的差异表达片段分别为20, 28, 16和21个。将这些差异表达片段对20个晚疫病病菌个体进行无毒基因差异表达验证, 得到1 个无毒基因连锁群Avr3-Avr10-Avr11 的候选片段, 即A11T13Avr3-10-11S157; 无毒基因Avr4的候选片段2个, 即A24T19Avr4S122和A24T24Avr4S142。Blast分析表明: A11T13Avr3210211S157 与马铃薯晚疫病菌萌发孢子囊( germinating sporangium ) EST ( expressed sequence tag) 库中的序列PG001F10.XT7 同源; A24T19Avr4S122 与晚疫病菌萌发中静孢子( germinating cyst) EST库中的PH051G10.XT7部分序列完全一致, 而A24T24Avr4S142与PH051G10. XT7具有98%的同源性。这些结果将促进通过电子克隆并结合RACE (Rapid Amplification of cDNA Ends) 技术获得全长的无毒基因Avr4。  相似文献   

Apollo 11: exposure of lower animals to lunar material     

C A Benschoter  T C Allison  J F Boyd  M A Brooks  J W Campbell  R O Groves  A M Heimpel  H E Mills  S M Rays  J W Warren  K E Wolf  E M Wood  R T Wrenn  Z Zein-Eldin 《Science (New York, N.Y.)》1970,169(944):470-472

  相似文献   

Phytophthora genome sequences uncover evolutionary origins and mechanisms of pathogenesis   总被引：2，自引：0，他引：2  

Tyler BM  Tripathy S  Zhang X  Dehal P  Jiang RH  Aerts A  Arredondo FD  Baxter L  Bensasson D  Beynon JL  Chapman J  Damasceno CM  Dorrance AE  Dou D  Dickerman AW  Dubchak IL  Garbelotto M  Gijzen M  Gordon SG  Govers F  Grunwald NJ  Huang W  Ivors KL  Jones RW  Kamoun S  Krampis K  Lamour KH  Lee MK  McDonald WH  Medina M  Meijer HJ  Nordberg EK  Maclean DJ  Ospina-Giraldo MD  Morris PF  Phuntumart V  Putnam NH  Rash S  Rose JK  Sakihama Y  Salamov AA  Savidor A  Scheuring CF  Smith BM  Sobral BW  Terry A  Torto-Alalibo TA  Win J  Xu Z 《Science (New York, N.Y.)》2006,313(5791):1261-1266

Draft genome sequences have been determined for the soybean pathogen Phytophthora sojae and the sudden oak death pathogen Phytophthora ramorum. O?mycetes such as these Phytophthora species share the kingdom Stramenopila with photosynthetic algae such as diatoms, and the presence of many Phytophthora genes of probable phototroph origin supports a photosynthetic ancestry for the stramenopiles. Comparison of the two species' genomes reveals a rapid expansion and diversification of many protein families associated with plant infection such as hydrolases, ABC transporters, protein toxins, proteinase inhibitors, and, in particular, a superfamily of 700 proteins with similarity to known o?mycete avirulence genes.  相似文献