Tissue samples from Australian carpet pythons (Morelia spilota) with neurological disease were screened for viruses using next-generation sequencing. Coding complete genomes of two bornaviruses were identified with the gene order 3’-N-X-P-G-M-L, representing a transposition of the G and M genes compared to other bornaviruses and most mononegaviruses. Use of these viruses to search available vertebrate genomes enabled recognition of further endogenous bornavirus-like elements (EBLs) in diverse placental mammals, including humans. Codivergence patterns and shared integration sites revealed an ancestral laurasiatherian EBLG integration (77 million years ago [MYA]) and a previously identified afrotherian EBLG integration (83 MYA). The novel python bornaviruses clustered more closely with these EBLs than with other exogenous bornaviruses, suggesting that these viruses diverged from previously known bornaviruses prior to the end-Cretaceous (K-Pg) extinction, 66 MYA. It is possible that EBLs protected mammals from ancient bornaviral disease, providing a selective advantage in the recovery from the K-Pg extinction. A degenerate PCR primer set was developed to detect a highly conserved region of the bornaviral polymerase gene. It was used to detect 15 more genetically distinct bornaviruses from Australian pythons that represent a group that is likely to contain a number of novel species.

澳大利亚地毯蟒的组织样本（Morelia spilota使用新一代测序技术筛选患有神经系统疾病的病毒。用3'-NXPGML基因顺序鉴定了两个波塔病毒的完整基因组，与其他波塔病毒和大多数单核病毒相比，代表了G和M基因的转座。利用这些病毒搜索可用的脊椎动物基因组，可以识别包括人在内的各种胎盘哺乳动物中进一步的内源性波状病毒样元件（EBL）。共生模式和共享的整合站点揭示了祖先的劳拉西瑟式EBLG整合（7700万年前，MYA）和先前确定的非洲人EBLG整合（83 MYA）。与其他外源性博纳病毒相比，新型python博纳病毒与这些EBL的聚集更为紧密，提示这些病毒在白垩纪末期（K-Pg）灭绝（66 MYA）之前与先前已知的波纳病毒不同。EBLs可能保护哺乳动物免受古代新生儿病毒的侵袭，从而在K-Pg灭绝的恢复中提供选择性优势。开发了简并的PCR引物组，以检测新生儿病毒聚合酶基因的高度保守区域。它被用来检测来自澳大利亚蟒蛇的另外15种遗传上不同的波纳病毒，它们代表可能包含许多新物种的群体。开发了简并的PCR引物组，以检测新生儿病毒聚合酶基因的高度保守区域。它被用来检测来自澳大利亚蟒蛇的另外15种遗传上不同的波纳病毒，它们代表可能包含许多新物种的群体。开发了简并的PCR引物组，以检测新生儿病毒聚合酶基因的高度保守区域。它被用来检测来自澳大利亚蟒蛇的另外15种遗传上不同的波纳病毒，它们代表可能包含许多新物种的群体。