Noa-Carrazana Juan Carlos, González-de-León Diego, Silva-Rosales Laura
Cinvestav Campus Guanajuato, Apdo Postal 629, Irapuato, Gto, 36500, Mexico.
Virus Genes. 2007 Aug;35(1):109-17. doi: 10.1007/s11262-006-0039-y. Epub 2006 Nov 3.
The virus most often reported in papaya (Carica papaya L.) is papaya ringspot (PRSV). The aim of this work was the molecular genomic characterization of a Mexican severe isolate of PRSV-P "Mex-VrPO" (isolate from the State of Veracruz in Paso de Ovejas) as well as its comparison with other isolates from other world regions. The linear, assembled, single-strand positive sense RNA genome of PRSV-P Mex-VrPO was 10320 nt in length (excluding the poly(A) tail) and contained a single large predicted ORF with 3344 aa. The comparative analysis of our PRSV isolates and five others reported before, showed the most variable proteins were P1, P3, 6 K and CP with 13-33%, 5-7%, 6-9% and 5-9% divergence respectively. The most conserved ones were CI, NIb and HC-Pro (2-3%, 3-5% and 4-5%). The phylogenetic analysis showed a close relation between the Mexican (Mex-VrPO) and Hawaiian (PRSV-P HA) isolates. This work provided the first opportunity to establish the foundation for (1) understanding whole genome and polyprotein variability between Asian and American PRSV isolates, and (2) elucidating major trends in the relative evolution of viral cistrons as deduced from in silico recombination analyses.
番木瓜（番木瓜属）中最常报道的病毒是番木瓜环斑病毒（PRSV）。本研究的目的是对墨西哥PRSV-P的一个严重分离株“Mex-VrPO”（来自韦拉克鲁斯州帕索德奥韦哈斯的分离株）进行分子基因组特征分析，并将其与世界其他地区的其他分离株进行比较。PRSV-P Mex-VrPO的线性、组装好的单链正义RNA基因组长度为10320 nt（不包括poly(A)尾），包含一个单一的大预测开放阅读框，有3344个氨基酸。对我们的PRSV分离株与之前报道的其他五个分离株的比较分析表明，最可变的蛋白是P1、P3、6K和CP，差异分别为13-33%、5-7%、6-9%和5-9%。最保守的是CI、NIb和HC-Pro（2-3%、3-5%和4-5%）。系统发育分析表明，墨西哥（Mex-VrPO）和夏威夷（PRSV-P HA）分离株之间关系密切。这项工作首次为以下方面奠定了基础：（1）了解亚洲和美洲PRSV分离株之间的全基因组和多蛋白变异性；（2）阐明从计算机重组分析推断出的病毒顺反子相对进化的主要趋势。
