【目的】 本研究对杨扇舟蛾颗粒体病毒（Clostera anachoreta granulovirus ，ClanGV）的晚期表达因子（Late expression factors，LEFs）进行生物信息学分析，并对ClanGV的lefs与其它杆状病毒的lefs进行对比，对鉴定lef基因和研究ClanGV的感染机制具有重要意义。【方法】 使用ORF finder在线程序进行开放阅读框（ORFs）分析，BLASTP程序用于蛋白序列的同源分析，DNAStar和DNAClub生物学软件用于对序列进行处理和分析，采用BLAST在公共数据库中对序列进行比对，Clustal W Version 1.8 和 GeneDoc 2.7用于多序列的比对和分析，用MEGA 6.06的NJ法进行系统发育分析。【结果】 ClanGV基因组包括15个lef基因，分别为ie-1、lef-2、39k、lef-11、p35、p47、lef-1、lef-6、lef-5、lef-4、dnapol、lef-3、lef-9、lef-8 和 lef-10。ClanGV与云杉枞色卷蛾颗粒体病毒（Choristoneura occidentalis granulovirus，CoGV）、黄地老虎颗粒体病毒（Agrotis segetum granulovirus，AsGV）、苹果异形小卷蛾颗粒体病毒（Cryptophlebia leucotreta granulovirus，ClGV）、马铃薯块茎蛾颗粒体病毒（Phthorimaea operculella granulovirus，PoGV）和苹果蠹蛾颗粒体病毒（Cydia pomonella granulovirus，CpGV）有着较近的亲缘关系。颗粒体病毒中只有ClanGV和分月扇舟蛾颗粒体病毒含有p35。ClanGV的lef-2的转录方向不同于其它12个颗粒体病毒。γ和δ杆状病毒分别只含有7个和3个ClanGV的lef同源基因。Clan GV的lefs跟其它杆状病毒lefs的相似性较低，其中ClanGV与其它颗粒体病毒间的相似性高于Clan GV与核型多角体病毒间的相似性。Clan GV的lef-2、39k、p35、lef-5、dnapol和 lef-9在启动子上游拥有TATA box；p47和lef-1在TATA下游20~40 bp处还有一个CACT 基序；lef-11、p35、lef-6、lef-5、lef-3、lef-9、lef-8和 lef-10这8个基因有晚期启动子基序TAAG；而p35、lef-5、lef-9 和lef-10上游既有TATA 又有 TAAG基序。【结论】 结果为研究杆状病毒的基因功能和感染机制提供了数据基础。

[Objectives]  To identify late expression factor (LEF) genes and investigate the ClanGV infection mechanism. [Methods]  We analyzed the ClanGV LEF family of genes of Clostera anastomosis granulovirus, including gene identification and organization, gene sequences, and structural characteristics at the DNA and protein levels, and compared the data obtained with those on other baculoviruses. Open reading frames (ORFs) were confirmed using the ORF finder online program. Homology searches were carried out using the BLASTP program. Sequence data assembly and analysis were performed using DNAStar and DNAClub software. Sequence comparison in public databases was done using the BLASTprogram. Multiple sequence analysis was performed using ClustalW Version 1.8 and GeneDoc 2.7. Phylogenetic analysis was carried out with MEGA 4.0 software using the neighbor joining (NJ) distance method (1 000 bootstrap replicates). [Results]  Sequence analysis indicated that the C. anastomosis granulovirus ClanGV genome includes 15 LEF genes, annotated as ie-1, lef-2, 39k, lef-11, p35, p47, lef-1, lef-6, lef-5, lef-4, dnapol, lef-3, lef-9, lef-8 and lef-10, respectively. C. anastomosis granulovirus ClanGV shares higher homology with the Choristoneura occidentalis granulovirus, Agrotis segetum granulovirus, Cryptophlebia leucotreta granulovirus,  Phthorimaea operculella granulovirus, and the Cydia pomonella granulovirus, than with other granuloviruses. With the exception of 9 nucleopolyhedroviruses, P35 was only found in C. anastomosis granulovirus ClanGV and the C. anastomosis granulovirus. C. anastomosis granulovirus ClanGV lef-2 differed from that of the other 12 granuloviruses in transcription orientation. The nucleopolyhedrovirus belonging to gammabaculovirus and deltabaculovirus include 7 and 3 ClanGV lefs, respectively. C. anastomosis granulovirus ClanGV lefs have very low homology with baculoviruses, although their homology with granulovirus lefs is higher than with those of nucleopolyhedroviruses. C. anastomosis granulovirus ClanGV lef-2, 39k, p35, lef-5, dnapol, and lef-9, possess an early promoter motif (TATA). p47 and lef-1 have a CACT motif 20-40 bp downstream of TATA, and eight genes; lef-11, p35, lef-6, lef-5, lef-3, lef-9, lef-8, and lef-10, have a late promoter motif TAAG. However, only p35, lef-5, lef-9, and lef-10, possess both the TATA and TAAG. [Conclusion]  The results of this study are of considerable importance to research on the ClanGV granulovirus gene function and infection mechanism.