Bunyaviridae family is the largest and most diverse family of RNA viruses. It has more than 350 members divided into five genera: Orthobunyavirus, Phlebovirus, Nairovirus, Hantavirus, and Tospovirus. They are present in the five continents, causing recurrent epidemics, epizootics, and considerable agricultural loss. The genome of bunyaviruses is divided into three segments of negative single-stranded RNA according to their relative size: L (Large), M (Medium) and S (Small) segment. Bunyaviridae RNA-dependent RNA polymerase (RdRp) is encoded by the L segment, and is in charge of the replication and transcription of the viral RNA in the cytoplasm of the infected cell. Viral RdRps share a characteristic right hand-like structure with three subdomains: finger, palm, and thumb subdomains that define the formation of the catalytic cavity. In addition to the N-terminal endonuclease domain, eight conserved motifs (A–H) have been identified in the RdRp of Bunyaviridae. In this review, we have summarized the recent insights from the structural and functional studies of RdRp to understand the roles of different motifs shared by RdRps, the mechanism of viral RNA replication, genome segment packaging by the nucleoprotein, cap-snatching, mRNA transcription, and other RNA mechanisms of bunyaviruses.

Bunyaviridae家族是最大和最多样化的RNA病毒家族。它拥有超过350名成员分为五个属：Orthobunyavirus，白蛉，内罗毕病毒属，汉坦病毒和Tospovirus。它们存在于五大洲，导致反复流行，流行病和大量农业损失。布尼亚病毒的基因组根据其相对大小分为三个负单链RNA片段：L（大），M（中）和S（小）片段。Bunyaviridae RNA依赖性RNA聚合酶（RdRp）由L片段编码，并负责感染细胞的细胞质中病毒RNA的复制和转录。病毒RdRps具有一个特征性的右手状结构，具有三个子域：手指，手掌和拇指子域，它们定义了催化腔的形成。除N端核酸内切酶结构域外，在Bunyaviridae的RdRp中还鉴定出八个保守的基序（AH）。在这篇评论中