中文摘要：

模式识别受体（PRR）是生物体先天免疫系统中免疫受体的代表，对生物体的生存极为重要。克隆鉴定了家蚕的14个模式识别受体编码基因，包括10个肽聚糖识别蛋白（PGRP）基因和4个β-葡聚糖识别蛋白（βGRP）基因，并得到了BmPGRP—S3、BmPGRP-S4和BmPGRP-L5的完整编码序列。家蚕PGRP的长型和短型亚家族都具有典型的酰胺酶活性结构域，短型亚家族具有信号肽，长型亚家族则没有信号肽。5个PGRP长型亚家族基因成簇分布于第1号染色体；5个PGRP短型亚家族基因中有2个分布于第9号染色体，有3个分布于第16号染色体。家蚕βGRP家族成员都具有信号肽，其中BmβGRP1—3成簇分布于第11号染色体，编码蛋白不具有典型的葡聚糖结合结构域；BmβGRP4独立分布于第22号染色体，编码蛋白具有典型的葡聚糖结合结构域。基因芯片数据分析表明，BmPGRP-L5和BmβGRP1在5龄第3天幼虫各组织中没有表达，其余12个模式识别受体基因为多组织表达，但在丝腺组织中均无表达。在这12个模式识别受体基因中，BmPGRP-L3等6个模式识别受体基因在中肠组织中的表达水平偏高；BmβGRP3、BmβGRP4和BmPGRP—L3、BmPGRP—L4等在家蚕生殖腺中的表达水平较高。在生殖腺以外的其他各组织中，这12个基因的表达不具有雌雄差异性。BmβCRP1在家蚕各发育时期没有表达，BmPGRP—L5主要在变态发育的转折期表达，其余12个模式识别受体基因在各发育时期均有表达，并从5龄第3天幼虫到上蔟第2天有较高水平的表达，雌雄个体间无表达差异性。由此说明这些模式识别受体基因的表达具有一定的组织性和发育时期性。给人工饲料无菌饲养的家蚕5龄第3天幼虫分别添食大肠杆菌、家蚕黑胸败血菌和家蚕白僵菌，对免疫诱导3、6、12和24h的家蚕进行个体水平的实时荧光定量PCR检测，发现PGRP长型亚家族基因BmPGRP—L1、Bm

英文摘要：

Pattern recognition receptors （PRRs） are typical immunoreceptors of the organismal innate immune system, being vital to the survival of organisms. In present study, Bombyx mori genes encoding 14 PRRs were cloned and identified, including 10 for peptidoglycan recognition proteins （PGRPs） and 4 for β-glucan recognitionproteins （13GRPs）, and full coding sequences of BmPGRP-S3, BmPGRP-S4 and BmPGRP-L5 were obtained. In gene family of PGRP, typical amidase activity domain is predicted regardless of long- and short-type subfamilies. Short-type subfamily has signal peptide, but long-type subfamily does not have. 5 genes of long-type subfamily are located on chromosome 1 closely. Of short-type subfamily, 2 and 3 are located on chromosomes 9 and 16, respectively. All the βGRPs have signal peptide. BmβGRP1 -3 are located on chromosome 11 closely, and the glucan-binding region is not detected in them, whereas BmβGRP4 is located on chromosome 22 independently and has the typical glucan-binding domain. Microarray data showed that BmPGRP-L5 and BmβGRP1 were hardly detected in all tissues of day 3 fifth instar larvae, whereas the other 12 pattern recognition receptor genes were widely expressed in all tissues except silk gland. BmPGRP- L3 and other 5 receptor genes shared a relatively higher expression level in midgut, as well as the locations of BmβGRP3, BmβGRP4, BmPGRP-L3 and BmPGRP-L4 in gonad. All the 12 pattern recognition genes did not display sexbiased expression profile in all the organs except gonad. No transcription product of BmβGRP1 was detected during all developmental stages, whereas BmPGRP-L5 were mainly expressed in the turning stage of metamorphosis. The other 12 genes were persistently and non-sex-biasedly expressed during the developmental stages, especially higher from day 3 fifth instar larvae to pre-pupae. RT-qPCR analysis of the silkworm larval samples which were collected 3, 6, 12 and 24 hours after being administered with Escherichia coil, Bacillus bombysepticus, Beauveria bassiana,