Analysis of polymorphism and transcription of the effector gene Avr1b in Phytophthora sojae isolates from China virulent to Rps1b

• Published in: Molecular plant pathology Vol. 13; no. 2; pp. 114 - 122
• Main Authors: CUI, LINKAI, YIN, WEIXIAO, DONG, SUOMENG, WANG, YUANCHAO
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.02.2012; Blackwell
• Subjects: Alleles; Amino Acid Sequence; Biological and medical sciences; Breakpoints; China; Computational Biology; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Gene Deletion; Gene Expression Regulation; Gene polymorphism; Genes - genetics; Genome - genetics; Molecular Sequence Data; Mutation; Nucleotide sequence; Original; Phytopathology. Animal pests. Plant and forest protection; Phytophthora - genetics; Phytophthora - isolation & purification; Phytophthora - pathogenicity; Phytophthora sojae; Plant Diseases - microbiology; Polymerase chain reaction; Polymorphism, Genetic; Proteins - chemistry; Proteins - metabolism; Sequence Homology, Amino Acid; Soybeans; Transcription; Transcription, Genetic; transposase gene; Transposons; Virulence - genetics; Asia; China; Stramenopila; Phytophthora sojae; Plant pathogen; Gene; Transcription; Oomycota; Effector; Polymorphism
• ISSN: 1464-6722; 1364-3703
• DOI: 10.1111/j.1364-3703.2011.00733.x

SUMMARY The effector gene Avr1b‐1 of Phytophthora sojae determines the efficacy of the resistance gene Rps1b in soybean. The sequences of the Avr1b‐1 locus in 34 Chinese isolates of P. sojae were obtained and analysed by polymerase chain reaction (PCR) and inverse PCR. Four different alleles and a complete deletion mutation of the Avr1b‐1 gene were identified. Molecular analysis of the deletion breakpoints in the Avr1b‐1 locus revealed that an 8‐kb DNA sequence containing Avr1b‐1 was deleted and a 12.7‐kb DNA sequence was inserted at the same locus. A truncated transposase gene was found and five transposable elements were predicted in the inserted sequence, suggesting that the deletion of Avr1b‐1 might be attributed to transposon movement. The transcription of Avr1b‐1 was analysed in virulent isolates containing four alleles of Avr1b‐1 by real‐time reverse transcription‐PCR. In all virulent isolates, only those isolates containing the second allele transcripted Avr1b‐1.