Shim Hyekyung, Min Yeonju, Hong Sungyoul, Kwon Moonsik, Kim Daehyun, Kim Hyunran, Choi Yongmoon, Lee Sukchan, Yang Jaemyung
Department of Genetic Engineering, Sungkyunkwan University, Suwon 440-746, Korea.
Mol Cells. 2004 Oct 31;18(2):192-9.
Pear black necrotic leaf spot (PBNLS) is a disease of pears caused by capillovirus-like particles, which can be observed under the electron microscope. The disease was analyzed by Western blot analysis with antisera raised against apple stem grooving virus (ASGV) coat protein. cDNAs covering the entire genome were synthesized by RT-PCR and RACE using RNA isolated from Chenopodium quinoa infected with sap extracted from pear leaves carrying black necrotic spot disease. The complete genome sequence of the putative pear virus, 6497 nucleotides in length excluding the poly (A) tail, was determined and analyzed. It contains two overlapping open reading frames (ORFs). ORF1, spans from nucleotide position 37 to 6354, producing a putative protein of 241 kDa. ORF2, which is in a different reading frame within ORF1, begins at nucleotide 4788 and terminates at 5750, and produces a putative protein of 36 kDa. The 241 kDa protein contains sequences related to the NTP-binding motifs of helicases and RNA-dependent RNA polymerases. The 36-kDa protein contains the consensus sequence GDSG found in the active sites of several cellular and viral serine proteases. Morphological and serological analysis, and sequence comparison between the putative pear virus, ASGV, citrus tatter leaf virus and cherry virus A of the capillovirus suggest that PBNLS may be caused by a Korean isolate of ASGV.
梨黑坏死叶斑病（PBNLS）是一种由类毛病毒样颗粒引起的梨树病害，可在电子显微镜下观察到。用抗苹果茎沟病毒（ASGV）外壳蛋白产生的抗血清通过蛋白质免疫印迹分析对该病进行了分析。使用从感染了携带黑坏死斑病梨叶提取液的藜麦中分离的RNA，通过逆转录聚合酶链反应（RT-PCR）和cDNA末端快速扩增（RACE）合成了覆盖整个基因组的cDNA。测定并分析了假定梨病毒的完整基因组序列，其长度为6497个核苷酸，不包括聚腺苷酸（A）尾。它包含两个重叠的开放阅读框（ORF）。ORF1跨度为核苷酸位置37至6354，产生一个假定的241 kDa蛋白质。ORF2位于ORF1内的不同阅读框中，从核苷酸4788开始，在5750处终止，并产生一个假定的36 kDa蛋白质。2４1 kDa蛋白质包含与解旋酶和RNA依赖性RNA聚合酶的NTP结合基序相关的序列。36 kDa蛋白质包含在几种细胞和病毒丝氨酸蛋白酶活性位点中发现的共有序列GDSG。形态学和血清学分析，以及假定梨病毒、ASGV、柑橘碎叶病毒和毛病毒属的樱桃病毒A之间的序列比较表明，PBNLS可能由ASGV的韩国分离株引起。
